nyrobbie77

argh - should read both radiator hoses are NOW getting warm/hot.

nyrobbie77

got a free version of vag-com but having trouble getting it to work. won't communicate w/the vehicle.

i disconnected both heater hoses at the firewall and sprayed the hose through to see if the valves were stuck closed or heater core blocked. water flowed through both directions fine. ran it for some time to make sure it wasn't just looping through the valves and back out. ran the hose through the heater hoses towards the engine in both directions, again water flowed out just fine.

i let the car get up to temp, revved the engine and opend the bleeders a few times and got fluid out of both bleeders. i had thought the lower heater hose had been getting hot, but it seems like its just heat soak from the exhaust temp. if i grab either heater hose on the other side of the firewall right after the bleeders, both hoses are stone cold. i can reach both hoses at the heater core connections and again, both stone cold.

i'm running out of ideas on what to check. hopefully i can get vag com to work, mbe there's a code somewhere that'll help out. if anyone has any ideas, feel free to let me know.

thanks in advance

silverd2

Something is very wrong...very clogged(?).

The upper heater hose is the supply (in) hose for the heaters..it should always be as hot as any hose on a warm motor and full pressure any time it's running. That hose is connected to the pipe on the back of the motor, which is connected to the rear of both heads and is coolant exiting the motor...hottest coolant in the system, if all is correct.

I don't believe Vagcom will tell you much about this...sounds like a physical problem.

nyrobbie77

yikes... if i squeeze either of those heater hoses, it feels like there isn't much there fluid wise. m'be there is a plugged area in the block/passages. tomorrow i'll open the drain plugs on the block and see what comes out. the coolant from the radiator when i drained it before was very new/clean looking, as well as what came out of the lines going to the heater core.

only other thing i could think of is the water pump isn't pumping, but thats pretty rare of a failure on any car.

Nollywood

Water pump failures are not rare at all. Quite a high number of modern VAG engines have water pumps with plastic impellers. The impeller can crack where the shaft runs through it.

This will cause the engine to run hotter the faster it's run, as the impeller will slip at higher rpm. Not sure if this is the problem in your case, but I wouldn't rule it out.

nyrobbie77

well todays attempts... drained the block from both drain plugs and the radiator. disconnected the hoses at the firewall for the heater core and ran the hose thru the reservoir and both heater hoses with the block drain plugs removed. water flowed without any problem, all the coolant and water that came out was clean.

flushed out the after run pump and heater core again. only noted that only a small amount of hose pressure could be used, but the water came out fine and clean. i even disconnected the hose after the pump going to the heater core and water flowed fine through the pump and the core.

performed a chemical flush. this was the only time that the temp gauge went past the first big mark (about 1/4), gauge went to about half but no more. the flush said to fill with clean water and the flush chemical and run for 10mins after getting to temp. noted that the water boiled in the reservoir tank. both radiator hoses warm/hot, but both heater core hoses still cold.

let the engine cool down and then drained the flush/water mix from the radiator and both engine block drain plugs. topped back up with coolant and let get to temp.

for fun, i decided to disconnect the heater hoses at the firewall while the engine was running. at idle and with throttle, no coolant came out of either hose... i'm not sure that the t-stat opened yet, but water should still flow from the hoses right? definately not a good sign.

so this prolly means that the water pump isn't pumping right? i still don't think it is the headgaskets like the one shop thought. no coolant in oil or oil in coolant. plugs don't show any coolant burning, no overheating (tho i haven't driven it as i haven't got plates yet), no coolant smell from exhaust.

am running out of 40+ degree days to work on it. might have to get one of those turbo heaters or just wait till spring to replace the TB and water pump. i'm ok with doing that repair as the front right cam seal leaks like a siv when the engines running.

lemme know what u guys think. thanks again for all the advice

nyrobbie77

i guess rare was the wrong word to use... what i really meant was that the typical water pump failure is leakage or bearing failure, with the lesser being impeller failure. definately see it as a possibility and may actually be whats causing me to not have any coolant flow.

silverd2

Wow...unless you find a golf ball stuck in the coolant circuit, this is really beginning to sound like total pump failure. If all is clear and you don't get coolant gushing out the top heater hose, thermostat would have nothing to do with it....NO impeller action at all.
I would think that if the pump was seized, you'd be hearing it and smelling burning timing belt.
But, still...impeller failure is rare. Only in an astronomically high mileage American car, have I ever seen it...and that was corroded broken off metal blades.
Plastic impellers are not inherently defective or even less dependable than metal...seen em go 150K miles in perfect condition. Who knows? ...maybe someone else's past screw-up. Mixing other coolants with G-12 not only causes thick brown sludge to form, but is highly corrosive to plastics...I have seen that mistake lead to coolant leaks at plastic fittings in VW's.
Please take some pics when you get to the heart of the problem...sounds like it's time to look at that pump(?).

Nollywood

I have seen pump failure, whereby the shaft was slipping in the impeller. This was in my '03 A4 B6 3,0 quattro Tip. It was only at 57,000 miles, and a metal impeller too.

I replaced it, along with the timing belt and tensioner / idler, and it was fine. Prior to that, I had no heater, despite the coolant temperature rising at a steady 60 mph. At idle, the heater would blow lukewarm air, once I increased the rpm, it would go stone cold.

nyrobbie77

went back today and had to top off the coolant. guess i hadn't filled the block all the way back up. i get some coolant out of the bleeder now when i crack it open, but not what i'd expect. in a previous thread someone mentioned that when the bleeder was opened it sprayed farther than he could pee in the 3rd grade.. haha... it definately doesn't spray for me, just runs out. mbe the ole audi has some prostate problems...

i can't feel flow in the heater hoses by hand. i think i can feel it in the radiator hose. i do notice coolant flowing from the small top hose going into the reservoir tho, increases when i up the RPM's, so i think there must be some water pumping action going on.

drove it for a couple miles today. engine temp never raised past the first big mark, but never got heat. drove it hard and easy, no change.

when i had the heater hoses connected and the drain plugs out, water flowed easily out. only trouble i had was when i tried to spray water towards the heater core, had to use very little pressure, even when i bypassed the after run pump. i'm guessing this is because of the restrictions of the thin tubes of the core assembly?

is it possible that someone may have done either an intake gasket or head gasket and swapped gasket sides covering up a coolant passage? i'm just not sure if that'd be the problem cuz it drains fine when i spray down both heater hoses towards the block.

frustrated... thanks again for everyones help and comments.