Ok, so I did a search first and I can't find the answer. Here goes:

My 2001 Cavalier Z24 has a hig rev problem, notably upon startup and also intermittently when the car comes to a stop. Sometimes, it will rev all the way up to 4-5k range and stay there for a few seconds before winding back down. I took it to my mechanic, who hooked it to a diagnostics computer and got nothing. He took apart the engine, checked the gaskets, manifold, all the sensors. Everything was checked, changed, and fine. He also stated that the only thing left to check was the ECU, which could be pricey.

Here's the questions: Could it be ANYTHING else? I'm not high on rolling to the dealership for diagnostics and getting raped in charges.

Second, if it IS the ECU, I have found ONE that I can pick up for about $75. It's for an auto tranny car, which mine is a 5 speed. Would I just be better served to
pick up a new one specific for my car?

This is really the only thing wrong with the car and would hate to have to move on from it just for this. It's given me 140k care free miles on the original clutch to this point.

Finally, if you know any good shops in the San Fernando Valley that deal with Cavaliers, feel free to add that info, too!

Thanks guys, the NEWB appreciates it!

Mike

Check your iac sensor thats what it sounds like to me thats idle air control it may be failing


Erik Packard

My IAC was fine, I know my bcm is shot, it still idles high. I just don;t care. I will fix it when I boost. My car throws no codes so it does not know it has a problem. Been this way for a few years.

Sounds like you need a new mechanic, for starters.

I can't diagnose your problem over the internet... but any REAL mechanic should be able to in person.

John Lenko wrote:Sounds like you need a new mechanic, for starters.

I can't diagnose your problem over the internet... but any REAL mechanic should be able to in person.

LMAO. Well, the guy is nothing if not trustworthy and to be fair, he's been pretty adaptive to fixing everything else...on my Z28 and this car. He didn't charge me a dime for trying to diagnose and had it for a good while. Like Mike Demo said, the IAC and all sensors are fine with my car, too. The engine throws no codes whatsoever. It's good to hear that someone else has been rolling with the same problem for years and hasn't had the motor blow up on 'em.

My biggest grief is that taking it to a Chevy dealer will probably cost more to diagnose and fix than the car is worth. Like I said, though, the car has been SO trustworthy over the years that it would be a shame to let it go. Sorry, I guess I'm going all "cheap bastard" on y'all and it's only my 3rd or 4th post!

Yeah, it kind of is what it is. We had my car hooked into the shop diagnostics and played with changing the readings on the IAC, TPS and all the other sensors. We even disconnected them to see how the ecu would respond. It was weird, the sensors were good, we even swapped them with new ones (thanks NAPA) The lines tested good, teh sensors were good. We could use the programmer to change settings and see results, but the computer would not read things like the sensors not being connected, no code no issue.

What is odd is that when I hook in an aftermarket stereo, the gauge cluster reads error and the gauges die. No mileage recorded or anything. HMMMMMMMM

I can fix it.


C:\Users\Phillip\Pictures

3500gtp wrote:I can fix it.

Bold statement, diagnosis and repair thoughts?

Well, I broke down and took the car into the dealership today. I should know something by early next week at the latest. I will keep you all posted. I still think it's the ECU, though. BTW...here's a pic of the car in question.

I got money that says if you replace your FPR the problem will go away.. that is assuming your IAC is fine like you say it is.

OK, so here's the results. I took it to the local dealership (Rydell Northridge) and they got around to looking at the car after a couple of days. No rush...still had the Z28. Anyway, they adjusted the throttle body and TPS sensor. Voila! Problem gone. They did tell me, however, that if the throttle body goes bad, I will be hunting for parts as they didn't have one to replace mine with.

So there you have it, 143k miles and counting...the car stays! If I can figure out how to post a damn pic from google chrome, I'll do it. It still looks great after all this time.

I have some other stuff to take care of, but at some point, I will start looking on the site for the best short throw shifter, best aftermarket clutch, good suspension product...It would be nice to keep it for a long time.