91 v8 failed emissions
#1
91 v8 failed emissions
My sister just bought a 1991 quattro v-8, and it failed emissions. I've never worked on an Audi before, so I have a lot of questions.
After it failed the first time, I replaced the spark plugs and ran a fuel system cleaner through it. It passed the 2000rpm test, but failed the idle test. I blinked out the codes and got a 2342, so I replaced the oxygen sensor, changed the oil, and changed the air filter. It did a lot better, but still failed HC at idle. Now I get a 2341 code. I hadn't replaced the cap/rotor/wires because of the cost. I tested the wires with my multimeter, and all were 5-6k ohms except #4. I pulled the caps off, and they are burnt pretty bad. I decided to replace them, but I can't get the rotors off, and I don't want to break anything.
My questions are
1. Is there a trick to getting the rotors off, or do you just pull really hard?
2. Are there any other obvious things I should check with a 2341 code? (fuel pressure regulator diaphragm isn't ruptured)
3. The engine seems to have really weak vacuum, is that typical with these? Is that why they use hydro-boost?
Thanks for any help. I have read through the forums over the past week, but haven't been able to answer any of these questions.
After it failed the first time, I replaced the spark plugs and ran a fuel system cleaner through it. It passed the 2000rpm test, but failed the idle test. I blinked out the codes and got a 2342, so I replaced the oxygen sensor, changed the oil, and changed the air filter. It did a lot better, but still failed HC at idle. Now I get a 2341 code. I hadn't replaced the cap/rotor/wires because of the cost. I tested the wires with my multimeter, and all were 5-6k ohms except #4. I pulled the caps off, and they are burnt pretty bad. I decided to replace them, but I can't get the rotors off, and I don't want to break anything.
My questions are
1. Is there a trick to getting the rotors off, or do you just pull really hard?
2. Are there any other obvious things I should check with a 2341 code? (fuel pressure regulator diaphragm isn't ruptured)
3. The engine seems to have really weak vacuum, is that typical with these? Is that why they use hydro-boost?
Thanks for any help. I have read through the forums over the past week, but haven't been able to answer any of these questions.
#2
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Rotors are glued on, so only way to get them off is by crushing them with a pair of channelocks. Check for vacuum leaks...expecially the Carbon Canister Solenoid Valve that lives under the coolant reservoir...2piece design that when rubber get's old, can cause huge leak...If you need a used #4 wire, let me know. Good luck, Tom
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