IAC valve was OK now changing plugs/wires and O2 sensor to get rid of ruff idle, will report back.
12-20-2001, 08:53 PM
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Figure out the problem first! Save money and time!
Before going and spending the money and time changing things that might be perfectly good, figure out where the ruff idle is coming from. It could be the computer messing up (if your car has one) or it could be the O2 sensor, but the computer usually tells you if the control module and/or the O2 is out of wack. Have someone with a VAG 1552 tool look for error codes. If you plan on doing a lot of your own work go buy the www.ross-tech.com VAG 1552 toll for yourself and a full set of Bentley shop manuals.
I had a similar problem earlier this month. It ended up being a fuel injector. $80 bucks later and about 2 hours of my time, all fixed.
While running, and experiencing the ruff idle, pull spark plug wires off the spark plugs one at a time and listen for engine change. When you pull the plug wire on the bad jug, there will be little or no change in the ruff idle. When you pull a wire from a good jug you will know it. Now you have it narrowed down to the jug that is missing. (The VAG 1552 will probably tell you what jug is missing also)
Now figure out what is wrong. Is it missing because of a fuel injector, plug, induction air leak, valves, spark wires,... First thing to do is to see if the charge is coming down the plug wire. Pull the wire from the plug and hold close to a grounding point (be careful!!! Do not electrocute yourself). Is it sparking? Is it consistent? If not it may be the distributor or coil (or computer). Swap spark plug wires between the bad and a good jug (swap the entire wire not just the connection to the spark plug!). Now do the test pulling the wire of the previously missing jug. Is it still missing or did the problem move with the wire? If so it is the wire and replace the wire. If not, move on to the plugs. Swap plugs. Problem move with the swap? If no luck there, move 2 fuel injectors... You get the idea.
If it is an induction air problem (air leaking in somewhere that messes up the fuel air mixture to a jug, or multiple jugs) you can get a spray at the auto parts store that will help you find this problem. (By the way, an air leak shows up most at idle because of the critical mixture when the engine is running at idle) When you spray it around the engine head while running and there is a leak you will hear a temporary change in the engine rpm. If this is the case you may have a broken gasket somewhere. Unless you are really into your car mechanically, let the pros figure out and fix this one. May need a new head gasket.
If you still haven't figured it out after this, then it may be something internal. Bad compression in a cylinder because of rings or valves. Timing???????????
Hope this help you out. Good luck.
I had a similar problem earlier this month. It ended up being a fuel injector. $80 bucks later and about 2 hours of my time, all fixed.
While running, and experiencing the ruff idle, pull spark plug wires off the spark plugs one at a time and listen for engine change. When you pull the plug wire on the bad jug, there will be little or no change in the ruff idle. When you pull a wire from a good jug you will know it. Now you have it narrowed down to the jug that is missing. (The VAG 1552 will probably tell you what jug is missing also)
Now figure out what is wrong. Is it missing because of a fuel injector, plug, induction air leak, valves, spark wires,... First thing to do is to see if the charge is coming down the plug wire. Pull the wire from the plug and hold close to a grounding point (be careful!!! Do not electrocute yourself). Is it sparking? Is it consistent? If not it may be the distributor or coil (or computer). Swap spark plug wires between the bad and a good jug (swap the entire wire not just the connection to the spark plug!). Now do the test pulling the wire of the previously missing jug. Is it still missing or did the problem move with the wire? If so it is the wire and replace the wire. If not, move on to the plugs. Swap plugs. Problem move with the swap? If no luck there, move 2 fuel injectors... You get the idea.
If it is an induction air problem (air leaking in somewhere that messes up the fuel air mixture to a jug, or multiple jugs) you can get a spray at the auto parts store that will help you find this problem. (By the way, an air leak shows up most at idle because of the critical mixture when the engine is running at idle) When you spray it around the engine head while running and there is a leak you will hear a temporary change in the engine rpm. If this is the case you may have a broken gasket somewhere. Unless you are really into your car mechanically, let the pros figure out and fix this one. May need a new head gasket.
If you still haven't figured it out after this, then it may be something internal. Bad compression in a cylinder because of rings or valves. Timing???????????
Hope this help you out. Good luck.
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