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Simple enough:
My 2004 Hatchback has it's engine revving randomly up and down between idle and 2500 RPMs. it happens when it's at still, in park or in neutral.
It's only been happening recently, the mileage is 50700 ish and I have no idea what's causing it and I'm afraid of taking it to a dealer because they'll just charge me all sorts of stuff, but it might be my only option at this point, unless one of you guys has had the issue and got it fixed.
Kthx
never had it, but i can tell you a few ways of how to fine it..?
Throttle Positioning Sensor?
04 don't have that, they use a cableQuote:
Originally Posted by Wolfman AK907
Oh yeah, I forgot it went to drive by wire in 06'. What's your engine temp look like when it's doing this. If your thermostat is stuck open and pushing coolant into your motor when it first starts it may be in high idle trying to get up to temp. I really dont know, but that's what my s10 was doing for a while which is bad cause if you go for a longer than usual drive your coolant never gets a chance to actually cool down in the radiator before its forced backe into the motor which almost caused mine to over-heat.
its a senser somewhere, or something else. Check your power steering fluid.
04 also have throttle position sensor. Its the sensor that detect how big the opening is at the throttle.
This problem is caused by a leak in the vacuum. Check the small 5 cm rubber tube which link the engine head to throttle. If that leaks, it will cause this problem like this.
Ironically...
I just turned off the engine to my car in a parking lot nafter driving about 15 minutes and my engine started steaming...
Turns out the top hose going to the radiator from the engine broke and leaked out coolant.
I don't know if that's the direct cause of it but I do have a reason to take my car into the repair shop
(haha)
I dont have an explanation but my car has done this in the past. Though i have only experienced this anomaly on really cold days (about -15*c and lower)
already said... most likely a vacuum line is cracked, missing, broken, cut, listening to too much LOUD Rock and Roll Music.Quote:
Originally Posted by dmeech
Haha, that is a bit ironic :lol: . I don't think that's it though, It wouldn't idle up to 2500 on its own. I agree it must be a vacuum line or TPS. Maybe you should put some NOS Energy Drink in there...works on GSXR's. :lol:
I actually did have the engine light come on when i turned up my subs one day. went away shortly after but i thought it was pretty funny.
Yes, it wont rev anymore :lol:Quote:
Originally Posted by Wolfman AK907
AFM-(Air flow meter) ? Often the cause of the symptons you describe, can just be dirty , can usualy be cleaned with contact cleaner but often wont last long after cleaning , can usualy be found located in the air pipe running between the intake airbox and intake manifold.
Have a nosey around here http://gm.ws123.net/EN/ it's a fair cow to use and more handy than exact but better than nothing , well , nearly.
We dont have AFM/MAF, we have MAP sensors. Maybe the IAC (idle air controller) has gone southQuote:
Originally Posted by BASHO
So it turns out it was the air intake tube, the part just past the sensor, the clamp was loose and air was being sucked in on occasion and was messing with the engine CPU.
By the way, I got my radiator tube fixed, and just so you guys know there's a new part that wasn't a part of the original engine that connects the radiator hose to the engine. The old one is plastic and the new one is metal. I have an '04 aveo so the newer years might have it already.
Yeah, that's your thermostat housing. The plastic ones are junk! I think they swapped to metal in 06' but I'm not positive. It's stupid that they put those plastic ones on in the first place cuz up her in AK we have to run 195* thermostats to keep the heat up at -50* so they just dont hold up.
Lucky it was just your hose...My thermostat housing blew on me in rush-hour traffic. People behind me were NOT to happy...
I know this is an old post but, I need to revive it. My 04 also jumps up to 2500 at idle. So far I have replaced both vacuum lines that cross the intake, replaced the idle air control valve, removed throttle body and cleaned, replaced throttle position sensor, did the ecu idle relearn. Their are no coolant issues at all. Im stuck at this point, I am open to any suggestions someone may have. I do have the full AEM cai but, Ive had the idle issue roughly 6 months longer than Ive had the cai. Other than the cai, the engine is completely stock
check the o2 reading to see if the surge in idle is more fuel or more are (surge cause lean, or rich). Take that info to do an engine load comparison. And that should point you toward something. You seemed to address an air issue, which at idle would stall more likely unless the car started to add fuel to compensate (running lean when not surging). Or if you have too much fuel the car would be cutting fuel to bring the idle back down.. (running rich when not surging). You seemed to address all the air related possibilities exact the two intake sensors, check those. On the gas delivery side, it could be simply the warm up circuit, an injector, even bad o2. But check what your getting with the scan tool.
you guys also have the sticky throttle body issue.
[QUOTE=petrified.rabbit;150403]you guys also have the sticky throttle body issue.[/QUOTE
On the repairs list, I forgot to mention a new cat and new a/f ratio sensor (heated O2). I can monitor the O2, but at this point, I wouldnt be able to get a comparison reading unless you (rabbit) have reading or someone else on here, anytime im at idle its anywhere from 2000 to 2700 unless i hold the break and ride the clutch with it in gear to load the engine. With the engine under load, their is no idle issue. If im cruising at 60 and coast to a stop, as soon as it goes into neutral, or the clutch is fully pressed, idle jumps instantly. Here in a little while when I go to lunch, Ill hook my scantool up and see what I can get from the O2.
Their is no surge. When I start the car in neutral it jumps to 2500 and stays there until engine has a load. And it is not sparatic. first thing in the morning while engine is cold its high idle, an hour drive when engine is at operating temp, its still a high idle. Any time im at idle, its high.
I know this is an old thread, but, would like to share what I had on my 09 (E-Tech II engine, cable throttle). When brand new I had this issue, engine revving up to 2,000 and 2,500 and staying there while idle. Took to the dealer and they replaced the TPS sensor, it seemed to be fixed, but in a couple of days the issue was back, they now replaced the TPS connector, issue solved, until yesterday (4 and a half years after) the issue resurfaced, but with a slight difference, sometimes it feels that the engine is providing reduced power (less than usual :D) so, taking it to the mechanic tonight or tomorrow morning, will share the outcome.
Carlos
Just heard back from the mechanic, he checked the wiring and the connector, they were fine, he replaced the connector anyway, the issue was the actual TPS sensor this time.
Hi Carlos,
I’m sorry to hear that you were experiencing some concerns with your engine in your Aveo. I understand that you took your vehicle to the dealership for this concern and the problem returned. I also understand that you have taken your vehicle to a mechanic and now your concern is resolved. If you are to have any other concerns regarding your engine, please don’t hesitate to let us know and we will take an extra look into it. Also, if you have any questions or need any assistance with your vehicle, please feel free to let us know. Thanks for keeping us all updated!
Kristen A.
Chevrolet Customer Care
Thank You Kristem