Audi 100/A6 (C4 92-97) FAQ Digest
06-19-2007, 06:47 AM
#152
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OBDII connector pic - location
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06-27-2007, 07:15 AM
#153
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Roof Rack & Related "Worn out/water damaged" chrome pieces
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07-28-2007, 07:16 PM
#154
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Re: Cleaning the EGR System...comments
Spent the evening cleaning out the EGR passage in the intake manifold on my wife's 200k mile V6 A6q. Tried the instructions in the FAQ, but wasn't making much progress at the end of the passage where the temperature sensor enters the passage.
I have a loose intake from a parts motor. The EGR passage is clear on this one, and I can snake the string trimmer monofilament through the passage. However, the temp sensor still causes the monofilament to hang up a bit since it is installed at a corner.
I'd recommend removing the throttle body for a proper EGR cleaning. Pulling the throttle body allows access to the top of the EGR passage.
On the EGR passage in the car, carbon had built up from the passage about 3/8" above the floor of the manifold, and was rock hard. Even if you pushed through some of the carbon and made a hole, carb cleaner isn't enough to remove all of the buildup; it takes some scraping with a harder object than monofilament line. Leaving residual carbon would allow the passage to clog again fairly rapidly.
The throttle body was also very caked with oil and carbon, so I cleaned that while it was off. Removal also allows you to clean out the hard chunks of carbon and the other built up oil residue, and allows you to clean up the carb cleaner instead of leaving it in the intake.
Throttle body is held on with four internal hex bolts. You can leave most stuff connected and push the throttle body back to the firewall; I disconnected the throttle cable from the bracket but left it on the throttle body.
I might pull the valve covers; there's a bit of buildup at each breather hose and it might be clogged up on the inside.
Next time, I'll probably leave the EGR valve and pipe connected to the intake/exhaust. Pull the throttle body off completely, then pull the EGR temp sensor. Use oven cleaner then carb cleaner and get the passage clear at the intake end (which is where it clogs).
Chris Miller, c1j1miller@aol.com
I have a loose intake from a parts motor. The EGR passage is clear on this one, and I can snake the string trimmer monofilament through the passage. However, the temp sensor still causes the monofilament to hang up a bit since it is installed at a corner.
I'd recommend removing the throttle body for a proper EGR cleaning. Pulling the throttle body allows access to the top of the EGR passage.
On the EGR passage in the car, carbon had built up from the passage about 3/8" above the floor of the manifold, and was rock hard. Even if you pushed through some of the carbon and made a hole, carb cleaner isn't enough to remove all of the buildup; it takes some scraping with a harder object than monofilament line. Leaving residual carbon would allow the passage to clog again fairly rapidly.
The throttle body was also very caked with oil and carbon, so I cleaned that while it was off. Removal also allows you to clean out the hard chunks of carbon and the other built up oil residue, and allows you to clean up the carb cleaner instead of leaving it in the intake.
Throttle body is held on with four internal hex bolts. You can leave most stuff connected and push the throttle body back to the firewall; I disconnected the throttle cable from the bracket but left it on the throttle body.
I might pull the valve covers; there's a bit of buildup at each breather hose and it might be clogged up on the inside.
Next time, I'll probably leave the EGR valve and pipe connected to the intake/exhaust. Pull the throttle body off completely, then pull the EGR temp sensor. Use oven cleaner then carb cleaner and get the passage clear at the intake end (which is where it clogs).
Chris Miller, c1j1miller@aol.com
08-12-2007, 06:02 AM
#156
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TiKan's Great Audi Radios Summary Site
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09-11-2007, 05:53 PM
#157
Heater core replacement: step-by-step
Plan to be without the car for a few days, especially if you've not done this type of work before.
Take your time! You're working on the interior of your car and there are a lot of expensive and irreplaceable plastic, leather and vinyl parts that you don't want to break! Did I mention slow down and take your time?
Before you get started, I highly recommend you purchase and have in your hand, the correct heater core. This becomes a huge fiasco because there are 2 versions, and then there are umpteen different qualities and prices of these versions.
I've done this job 2 times in 4 months because the first time around I went cheap and ordered a $42.00 "Meyle" brand heater core. It's lower tank blew out completely, on the freeway, with my wife and daughter on board. The car instantly filled up with white steam, we could not see out, and boiling hot water blew all over our feet! I couldn't even keep my foot on the gas pedal because of the burning water.
The heater cores come with 2 different size fittings. 15mm or 18.5mm. My car takes the 18.5mm version and it was nearly impossible to find. I finally purchased one from the dealer for $133. Money well spent.
Start taking the interior apart first so your hands will be clean.
Tools needed at this stage:
-Philips screwdriver
-Slotted screwdriver
-Wide blade tool like a gasket scraper
-Dental pick
-Magnet (telescoping)
-8mm 1/4 drive socket
-10mm 1/4 drive socket
-12" long 1/4 drive extention
-6mm allen socket
Optional tools:
-I like to use my little Milwaulkie pistol grip screw driver. It's small, fast and does a great job on interior screws.
-I like to use wobbly sockets because it allows me to hit bolt and nut heads from an angle and that's really handy when doing interior work...which I've done a lot of, at the dealership level.
1) Remove the rear portion of the center console:
-Power both seats forward to expose the 8mm bolts at the rear sides of the center console.
-Remove the 2 bolts on each rear side of the console.
-Use a slotted screwdriver to carefully pop off the black plate that's below the center console's rear facing air vents.
-Use a philips screwdriver to remove the 2 screws you've just exposed.
-Power both seats fully back and fully down.
-Pop out the sides of the cup holders by grabbing up under their bottom edges and pulling the bottom edge outward. They're velcro'd in place.
-Pull out the carpet that's down inside the cup holder trough to expose the screw in the upper center of the trough.
-Remove the screw using a philips screwdriver
-Remove the rear facing air vents as one assembly. They'll just pull out now that you have the 3 screws removed.
-Pull up the hand brake lever. Underneath, right where the plastic handle meets the leather surround trim, you'll find a little plastic "lever". Flick it downward to release the plastic handle from the actual metal hand brake lever.
-Slide the plastic handbrake handle off.
-If your car has the differential lock button in the center console ('95 and older)use your flat screwdriver to carefully lift this switch assembly up and out, and then unplug the 2 connectors.
-Under the parking brake lever, just below the little lever you flicked down, is a black plastic plate. Pry it up from the rear and remove it to expose a 10mm bolt.
-Remove this 10mm bolt.
-Using something with a thin wide blade (I use a gasket scraper that I have, which is sort of like a dull wood chisel) Lever the tip down in under the rear area of the shifter wood trim, and pry down levering against the raise plastic center section of the shift console. Be careful...too much "point load" and you'll snap the wood trim!! You've been warned!! It comes up from the rear first, so work your finesse here.
-Lift the wood trim up and off.
-Unthread the shift handle.
-Remove the black plastic surround that was under the wood trim.
-Note that there is a light socket on the driver's side of the shift console. If your shift pattern doesn't light up, replace this little peanut bulb while you have the chance!
-You have expose 2 philips screws just below the wood trim. Remove them.
-The center console's rear section can now come out. Lift the front edge up a little to release the male/female plastic that engage, and then lift the rear, come forward, sliding the parking brake leather boot off, and then lift the console completely out. Be aware of any wires, like if you have an onboard phone with a speaker, etc.
Remove the front section of the center console:
-Near the 2 philips screws that you last removed, there are 2 8mm head bolts with heads facing inward, laying verticle. Remove them.
-Remove your radio(make sure you have your radio code!) using the "U" shaped tools into the 4 holes in the corners of the face. If you don't have the tools, make them out of a coat hanger. Bend about a 3" long U and then give the ends a bit of a barb. Push them into the holes in the radio, then force the U's outward toward the car doors to engage the barbs and drag the radio out.
-Remove the 3 electrical connectors, ground connector and antenna connector.
-Use your thin pry tool to carefully pry off the wood trim around the climate control. Go in at the top where the radio was.
-Remove the mirror switch by removing the 8mm bolt just below it. Unplug the electrical connector. If the 4 arrows on the round control button didn't light up in red, now is a good time to replace the 2 grain-of-wheat bulbs inside. This requires circuit board de-soldering and resoldering, but is very doable with bulbs and soldering tool from Radioshack.
-Remove the cigarette lighter the same way as above.
-Use your pry tool to pry off the black fake switches that are at the extreme left and right side of the bank of switches in the console.
-Now use your pry tool at these lower corners of the center vent assembly and pry out the center vent assembly. Remove it completely.
-You've exposed 2 10mm bolts with heads facing inward. They are the lower set of bolts. Remove them. Leave the upper set of 8mm bolts in place.
-Turn the ignition key on, step on the brake and move the shift lever back into 1st gear.
-Turn the ignition off.
-Working from the passenger side. Pull the center console back away from the dash.
-Once it's out far enough, get behind it and unplug the climate control head, and the bank of switches.
-Remove the console from the car.
Remove the Glove box:
-Open the glove box door.
-There are 2 10mm nuts in the upper corners and 2 10mm bolts in the lower corners. Remove all 4 and then lift the glove box slightly and finesse the entire box assembly toward you and down until you can get to the foam covered electrical plug at the rear.
-Slide the foam down the wire and unplug the connector.
-Remove the glove box from the car.
Remove the ducts:
-Remove the big air duct by gently pulling down from the dash corner's end and then pull to the right to get the other end off.
-Remove the big elbow there on the right side of the tunnel. Just rock it back and forth carefully where it engages the heater box, and then pull it down out of the defroster duct in the dash.
-Just behind this elbow is a 10mm bolt with head facing diagonally downward. Remove it.
-Now pull down on the foot duct that was being held in place by the 10mm bolt. Leave it loose, you don't need to take it out of the car.
-Over in the driver's footwell, things are a mirror image, but you don't need to remove the big upper duct or the lower driver's knee bolster.
-Just remove the big elbow.
-Remove the 10mm bolt that faced downward.
-Loosen the footwell duct and pull it down a bit.
-Finally, there is a red connector and a blue connector there where your center console was up against. Unplug the bottom connector from each. The upper connectors will stay with the heater box.
Removing the cowlings and wiper assembly:
-Open the hood.
-Remove the black rain tray by depressing the 4 silver metal clips along that gasketed seal, and lifing the tray up from them and pulling it at an angle toward the driver's side.
-Pop the black plastic caps off the wiper arm bases.
-Remove the 14mm bolts and wasthers that hold the wiper arm bases down.
-Close the hood (you don't need to latch it!)
-Fold the wiper arms into their "up" position and then rock them back and forth gently to brake the corrosion grip of the tapered wiper stalks.
-Remove both wiper arms.
-Open the hood.
-Using a 6mm allen, remove the 4 allen head bolts that hold the wiper cowl in place.
-Remove the cowl.
-Remove the 4 10mm bolts that hold the wiper arm assembly in place....2 at the passenger wiper transmission, 1 at the driver's transmission, 1 down at the base near the motor's mounting plate.
-Live the wiper assembly out enough to get to the electrical plug. Unplug that connector and remove the wiper assembly.
Removing the heater box:
-Use a slotted screwdriver to remove the hose clamps from the heater hoses on the driver's side of the box. The heater valve will stay with the box, so remove the hose from it. Leave it and the short bleeder hose attached to the box.
-Loosen the screw that holds the metal strap and then unclip the metal strap from down along the sides of the heater box.
-Unplug the electrical connectors on the driver's side of the box.
-Unplug the vacuum lines from the driver's side of the box and move all this stuff foward toward that space at the firewall.
-loosen the hose clamp on the big rubber boot over on the passenger side of the heater box.
-Unscrew the 3 philips screws that hold the flap motor box lid to the the Evaporator core box, right there next to the big rubber boot.
-Inside this box, remove 3 more philips screws and lift out the flap motor. Set it there out of the way.
-Now reach down into the rubber boot and swing that big round yellow door out of the way, so the heater box can be lifted out without damaging the flap.
-The heater box is no ready to come out. It is glued to the body of the car and my take some finessing. Slow steady prying by grabbing the curved fan motor area on the driver's side is best. I usually lay some thick blankets on the engine and get up on the engine so I can get a better pry angle with my body. Slowly work at breaking the seal. You can push from the inside of the car too. BE REALLY CAREFUL. BREAK THIS BOX AND YOU'RE SCREWED!!!!
-Continue working on the box until you have lifted it out.
Heater box dismantling:
-Go around the outside seam of the box and unclip all the metal clips you can see right now.
-Do the same thing with all the philips screws.
-At the blower motor end, remove the heater valve, the bleeder pipe, and then the little curved vacuum storage tank.
-Remove the big screw you see down inside that round blower area (under where the vacuum tank was).
-On the other side of the blower, remove the 3 philips screws and then take out the big round duct. The blower motor stays in place.
-At the end of the box where the red and blue connectors are, remove the screws at the left and right sides that hold the red and blue flap arms to the flap shafts. Slide the arms off the shafts.
-You've now exposed 2 more screws that hold this flap motor/duct assembly to the heater box.
-Remove these 2 screws.
-Remove this assembly from the heater box, it has a sort of clip on each side, so work around those as they hang up on you.
-You've now uncovered another 2 metal clips. Remove them.
-Just above this area on the driver's side of the box is a "C" clip over the end of a flap shaft. Remove it.
-On the driver's side of the box is a flap motor assembly. Remove the 6 or so screws that hold the cover in place.
-Remove the screws inside that hold the flap motor in place.
-Remove the "C" clip that holds this flap motor's arm to a flap's shaft. There is a metal wave washer and felt bushing that come off too.
-You've expose another big screw down in deep.
-Look around the box on the passenger side in it's middle areas from the side view, and find there are a couple more big philips screws down in the middle. Use a flashlight to locate them!
-With all these fasteners removed, lay the box on it's passenger side and remove the driver's side.
-The heater core is silicone glued to the driver's side.
-Cut the glue away and remove the busted heater core.
Now you need to clean the coolant out of the heater box and flaps, and all the duct work that is in your dash, etc.
I recommend that you don't disturb the flap positions, just work around them.
Putting it all back together is just a reversal of what I've written.
Make sure you buy some new closed cell foam so you can make a new seal for the heater box between the box and the body of the car.
The fittings end of the heater core is glued in place with a boat load of 100% silicone sealant. Don't forget to do that. Also, the new core should have foam round the top and bottom perimeter, as well as along the sides and bottom. You want airflow to only go one way....through the core's matrix, not around it.
When you go back together with the flap arms, they'll only articulate and go back together one way. Just be careful!
If you had flap motors that weren't working, now is the time to take them apart and clean the brushes and contacts in them. Or order new ones for $90ea.
A tip on installing the newly assembled heat/blower box unit(from a recent post on the forum):
Only thing I would add concerns the connector boot from the blower assembly to the internal ductwork. Take out the boot and install it over the blower exhaust first, then feed the entire unit through the opening.
Bleeding the coolant:
Note the bleeder screw in that hose that was between the heater valve and the heater core fitting. This is your friend....your fragile plastic friend!
Fire the car up, unscrew this bleed screw, turn the heat on high in the car, and run the engine at about 1,500rpm to get a good wave of coolant circulating. When you have a steady stream of coolant coming out of this bleeder, and heat coming out of your vents in the car, then close the bleeder screw (don't over tighten) and top off the coolant, and put the cap on the coolant tank. Make sure your cooling fans cycle! Make sure to add some more coolant after letting the engine cool down for a bit.
Hope this has helped speed up an ugly job. Tear down is fast. I can get the heater core in my hand in about 1hr and 40min. But going back together is a slower process, so take your time. You don't want to break anything and you don't want to forget something that causes you to take it all back apart again. Try to think in terms of "When I'm done, I don't want anyone to be able to tell I did this.
Take your time! You're working on the interior of your car and there are a lot of expensive and irreplaceable plastic, leather and vinyl parts that you don't want to break! Did I mention slow down and take your time?
Before you get started, I highly recommend you purchase and have in your hand, the correct heater core. This becomes a huge fiasco because there are 2 versions, and then there are umpteen different qualities and prices of these versions.
I've done this job 2 times in 4 months because the first time around I went cheap and ordered a $42.00 "Meyle" brand heater core. It's lower tank blew out completely, on the freeway, with my wife and daughter on board. The car instantly filled up with white steam, we could not see out, and boiling hot water blew all over our feet! I couldn't even keep my foot on the gas pedal because of the burning water.
The heater cores come with 2 different size fittings. 15mm or 18.5mm. My car takes the 18.5mm version and it was nearly impossible to find. I finally purchased one from the dealer for $133. Money well spent.
Start taking the interior apart first so your hands will be clean.
Tools needed at this stage:
-Philips screwdriver
-Slotted screwdriver
-Wide blade tool like a gasket scraper
-Dental pick
-Magnet (telescoping)
-8mm 1/4 drive socket
-10mm 1/4 drive socket
-12" long 1/4 drive extention
-6mm allen socket
Optional tools:
-I like to use my little Milwaulkie pistol grip screw driver. It's small, fast and does a great job on interior screws.
-I like to use wobbly sockets because it allows me to hit bolt and nut heads from an angle and that's really handy when doing interior work...which I've done a lot of, at the dealership level.
1) Remove the rear portion of the center console:
-Power both seats forward to expose the 8mm bolts at the rear sides of the center console.
-Remove the 2 bolts on each rear side of the console.
-Use a slotted screwdriver to carefully pop off the black plate that's below the center console's rear facing air vents.
-Use a philips screwdriver to remove the 2 screws you've just exposed.
-Power both seats fully back and fully down.
-Pop out the sides of the cup holders by grabbing up under their bottom edges and pulling the bottom edge outward. They're velcro'd in place.
-Pull out the carpet that's down inside the cup holder trough to expose the screw in the upper center of the trough.
-Remove the screw using a philips screwdriver
-Remove the rear facing air vents as one assembly. They'll just pull out now that you have the 3 screws removed.
-Pull up the hand brake lever. Underneath, right where the plastic handle meets the leather surround trim, you'll find a little plastic "lever". Flick it downward to release the plastic handle from the actual metal hand brake lever.
-Slide the plastic handbrake handle off.
-If your car has the differential lock button in the center console ('95 and older)use your flat screwdriver to carefully lift this switch assembly up and out, and then unplug the 2 connectors.
-Under the parking brake lever, just below the little lever you flicked down, is a black plastic plate. Pry it up from the rear and remove it to expose a 10mm bolt.
-Remove this 10mm bolt.
-Using something with a thin wide blade (I use a gasket scraper that I have, which is sort of like a dull wood chisel) Lever the tip down in under the rear area of the shifter wood trim, and pry down levering against the raise plastic center section of the shift console. Be careful...too much "point load" and you'll snap the wood trim!! You've been warned!! It comes up from the rear first, so work your finesse here.
-Lift the wood trim up and off.
-Unthread the shift handle.
-Remove the black plastic surround that was under the wood trim.
-Note that there is a light socket on the driver's side of the shift console. If your shift pattern doesn't light up, replace this little peanut bulb while you have the chance!
-You have expose 2 philips screws just below the wood trim. Remove them.
-The center console's rear section can now come out. Lift the front edge up a little to release the male/female plastic that engage, and then lift the rear, come forward, sliding the parking brake leather boot off, and then lift the console completely out. Be aware of any wires, like if you have an onboard phone with a speaker, etc.
Remove the front section of the center console:
-Near the 2 philips screws that you last removed, there are 2 8mm head bolts with heads facing inward, laying verticle. Remove them.
-Remove your radio(make sure you have your radio code!) using the "U" shaped tools into the 4 holes in the corners of the face. If you don't have the tools, make them out of a coat hanger. Bend about a 3" long U and then give the ends a bit of a barb. Push them into the holes in the radio, then force the U's outward toward the car doors to engage the barbs and drag the radio out.
-Remove the 3 electrical connectors, ground connector and antenna connector.
-Use your thin pry tool to carefully pry off the wood trim around the climate control. Go in at the top where the radio was.
-Remove the mirror switch by removing the 8mm bolt just below it. Unplug the electrical connector. If the 4 arrows on the round control button didn't light up in red, now is a good time to replace the 2 grain-of-wheat bulbs inside. This requires circuit board de-soldering and resoldering, but is very doable with bulbs and soldering tool from Radioshack.
-Remove the cigarette lighter the same way as above.
-Use your pry tool to pry off the black fake switches that are at the extreme left and right side of the bank of switches in the console.
-Now use your pry tool at these lower corners of the center vent assembly and pry out the center vent assembly. Remove it completely.
-You've exposed 2 10mm bolts with heads facing inward. They are the lower set of bolts. Remove them. Leave the upper set of 8mm bolts in place.
-Turn the ignition key on, step on the brake and move the shift lever back into 1st gear.
-Turn the ignition off.
-Working from the passenger side. Pull the center console back away from the dash.
-Once it's out far enough, get behind it and unplug the climate control head, and the bank of switches.
-Remove the console from the car.
Remove the Glove box:
-Open the glove box door.
-There are 2 10mm nuts in the upper corners and 2 10mm bolts in the lower corners. Remove all 4 and then lift the glove box slightly and finesse the entire box assembly toward you and down until you can get to the foam covered electrical plug at the rear.
-Slide the foam down the wire and unplug the connector.
-Remove the glove box from the car.
Remove the ducts:
-Remove the big air duct by gently pulling down from the dash corner's end and then pull to the right to get the other end off.
-Remove the big elbow there on the right side of the tunnel. Just rock it back and forth carefully where it engages the heater box, and then pull it down out of the defroster duct in the dash.
-Just behind this elbow is a 10mm bolt with head facing diagonally downward. Remove it.
-Now pull down on the foot duct that was being held in place by the 10mm bolt. Leave it loose, you don't need to take it out of the car.
-Over in the driver's footwell, things are a mirror image, but you don't need to remove the big upper duct or the lower driver's knee bolster.
-Just remove the big elbow.
-Remove the 10mm bolt that faced downward.
-Loosen the footwell duct and pull it down a bit.
-Finally, there is a red connector and a blue connector there where your center console was up against. Unplug the bottom connector from each. The upper connectors will stay with the heater box.
Removing the cowlings and wiper assembly:
-Open the hood.
-Remove the black rain tray by depressing the 4 silver metal clips along that gasketed seal, and lifing the tray up from them and pulling it at an angle toward the driver's side.
-Pop the black plastic caps off the wiper arm bases.
-Remove the 14mm bolts and wasthers that hold the wiper arm bases down.
-Close the hood (you don't need to latch it!)
-Fold the wiper arms into their "up" position and then rock them back and forth gently to brake the corrosion grip of the tapered wiper stalks.
-Remove both wiper arms.
-Open the hood.
-Using a 6mm allen, remove the 4 allen head bolts that hold the wiper cowl in place.
-Remove the cowl.
-Remove the 4 10mm bolts that hold the wiper arm assembly in place....2 at the passenger wiper transmission, 1 at the driver's transmission, 1 down at the base near the motor's mounting plate.
-Live the wiper assembly out enough to get to the electrical plug. Unplug that connector and remove the wiper assembly.
Removing the heater box:
-Use a slotted screwdriver to remove the hose clamps from the heater hoses on the driver's side of the box. The heater valve will stay with the box, so remove the hose from it. Leave it and the short bleeder hose attached to the box.
-Loosen the screw that holds the metal strap and then unclip the metal strap from down along the sides of the heater box.
-Unplug the electrical connectors on the driver's side of the box.
-Unplug the vacuum lines from the driver's side of the box and move all this stuff foward toward that space at the firewall.
-loosen the hose clamp on the big rubber boot over on the passenger side of the heater box.
-Unscrew the 3 philips screws that hold the flap motor box lid to the the Evaporator core box, right there next to the big rubber boot.
-Inside this box, remove 3 more philips screws and lift out the flap motor. Set it there out of the way.
-Now reach down into the rubber boot and swing that big round yellow door out of the way, so the heater box can be lifted out without damaging the flap.
-The heater box is no ready to come out. It is glued to the body of the car and my take some finessing. Slow steady prying by grabbing the curved fan motor area on the driver's side is best. I usually lay some thick blankets on the engine and get up on the engine so I can get a better pry angle with my body. Slowly work at breaking the seal. You can push from the inside of the car too. BE REALLY CAREFUL. BREAK THIS BOX AND YOU'RE SCREWED!!!!
-Continue working on the box until you have lifted it out.
Heater box dismantling:
-Go around the outside seam of the box and unclip all the metal clips you can see right now.
-Do the same thing with all the philips screws.
-At the blower motor end, remove the heater valve, the bleeder pipe, and then the little curved vacuum storage tank.
-Remove the big screw you see down inside that round blower area (under where the vacuum tank was).
-On the other side of the blower, remove the 3 philips screws and then take out the big round duct. The blower motor stays in place.
-At the end of the box where the red and blue connectors are, remove the screws at the left and right sides that hold the red and blue flap arms to the flap shafts. Slide the arms off the shafts.
-You've now exposed 2 more screws that hold this flap motor/duct assembly to the heater box.
-Remove these 2 screws.
-Remove this assembly from the heater box, it has a sort of clip on each side, so work around those as they hang up on you.
-You've now uncovered another 2 metal clips. Remove them.
-Just above this area on the driver's side of the box is a "C" clip over the end of a flap shaft. Remove it.
-On the driver's side of the box is a flap motor assembly. Remove the 6 or so screws that hold the cover in place.
-Remove the screws inside that hold the flap motor in place.
-Remove the "C" clip that holds this flap motor's arm to a flap's shaft. There is a metal wave washer and felt bushing that come off too.
-You've expose another big screw down in deep.
-Look around the box on the passenger side in it's middle areas from the side view, and find there are a couple more big philips screws down in the middle. Use a flashlight to locate them!
-With all these fasteners removed, lay the box on it's passenger side and remove the driver's side.
-The heater core is silicone glued to the driver's side.
-Cut the glue away and remove the busted heater core.
Now you need to clean the coolant out of the heater box and flaps, and all the duct work that is in your dash, etc.
I recommend that you don't disturb the flap positions, just work around them.
Putting it all back together is just a reversal of what I've written.
Make sure you buy some new closed cell foam so you can make a new seal for the heater box between the box and the body of the car.
The fittings end of the heater core is glued in place with a boat load of 100% silicone sealant. Don't forget to do that. Also, the new core should have foam round the top and bottom perimeter, as well as along the sides and bottom. You want airflow to only go one way....through the core's matrix, not around it.
When you go back together with the flap arms, they'll only articulate and go back together one way. Just be careful!
If you had flap motors that weren't working, now is the time to take them apart and clean the brushes and contacts in them. Or order new ones for $90ea.
A tip on installing the newly assembled heat/blower box unit(from a recent post on the forum):
Only thing I would add concerns the connector boot from the blower assembly to the internal ductwork. Take out the boot and install it over the blower exhaust first, then feed the entire unit through the opening.
Bleeding the coolant:
Note the bleeder screw in that hose that was between the heater valve and the heater core fitting. This is your friend....your fragile plastic friend!
Fire the car up, unscrew this bleed screw, turn the heat on high in the car, and run the engine at about 1,500rpm to get a good wave of coolant circulating. When you have a steady stream of coolant coming out of this bleeder, and heat coming out of your vents in the car, then close the bleeder screw (don't over tighten) and top off the coolant, and put the cap on the coolant tank. Make sure your cooling fans cycle! Make sure to add some more coolant after letting the engine cool down for a bit.
Hope this has helped speed up an ugly job. Tear down is fast. I can get the heater core in my hand in about 1hr and 40min. But going back together is a slower process, so take your time. You don't want to break anything and you don't want to forget something that causes you to take it all back apart again. Try to think in terms of "When I'm done, I don't want anyone to be able to tell I did this.
09-12-2007, 03:50 AM
#158
A few more details
<a href="https://forums.audiworld.com/s4s6/msgs/78079.phtml">https://forums.audiworld.com/s4s6/msgs/78079.phtml</a>
<a href="https://forums.audiworld.com/a6100/msgs/78284.phtml">https://forums.audiworld.com/a6100/msgs/78284.phtml</a>
<a href="https://forums.audiworld.com/a6100/msgs/78284.phtml">https://forums.audiworld.com/a6100/msgs/78284.phtml</a>
09-12-2007, 06:58 AM
#159
One little snag...
The side panels on my center console, and I assume other C4's, have clips up front (hidden under the carpet) that do a sliding male/female thing as the console is pushed forward toward the firewall during installation.
If I were to grab these side panels and simple pull them away from the tunnel, it would break the clips and if it didn't, it would dissengage them and then they couldn't be reconnected without moving the console rearward, lining the clips up and then pushing foward.
Watcha think?
If I were to grab these side panels and simple pull them away from the tunnel, it would break the clips and if it didn't, it would dissengage them and then they couldn't be reconnected without moving the console rearward, lining the clips up and then pushing foward.
Watcha think?