I have a beloved 1997 Toyota Camry automatic V6 with a young 130,000 miles on it. The past few months after driving for maybe 10 minutes the the tachometer get finicky and starts to fluctuate, bouncing slightly high and low. This is an extreme problem because as I come to a stop, the car shakes and often will stall if the bouncing idle hits <150RPMs. Now if I suddenly gas it, giving it a great start off the line, it “fixes” the problem and gives me at least 10 minutes of the normal regular idle. It initially on got finicky once a month, then once a week, and now it’s almost everytime I drive the car; and this morning decided on startup to just go ahead and idle funny and stall a few times. Any advice for a poor graduate student??
Check Engine Light? If so, get the codes read at Autozone or someplace similar and post them. My first guess would be that the EGR (Exhaust Gas Recycle) valve is sticking open sometimes, but it could be lots of other things.
The next time this fluctuating idle occurs, open the hood and tap on the idle air valve with the handle of a screwdriver. If the idle settles down, the idle air valve is hunting which means it requires replacement.
Tester
If you have not had the throttle body cleaned in a while, have that done with special emphasis on the idle air passage. This will usually cure a sticking IAC valve.
Hope that helps.
You guys are great! It was the EGR valve. Thanks!
The local mechanics gave me the option of replacing it ($450!!!) or they can disconnect it which would solve the idle and stalling problem. I am a poor graduate student, would there be any long-term problems with just disconnecting it?? (The local mechanics never answered this). I’m in Florida so there are no emission laws here.
It could lead to engine knocking, which can lead to total engine failure, or it could be okay. It’s your gamble.
Thanks for the feedback. Without the EGR system operating, you are going to have to take over the job. When you hear the engine knocking, you will have to back out of the throttle until it abates. You will be accelerating more slowly and climbing hills at a slower pace. You will be spewing more nitrous oxides into the atmosphere.
I would also not hesitate to get a second opinion and estimate. Do you know what was done to check the EGR valve? B/c the EGR is a “system” of which the valve is one part. Sometimes people just replace parts without full diagnosis.
As for the second estimate, $450 just looks a bit steep to me.