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Discussion Starter #1 (Edited)
Hey all, I have cleaned my throttle body and now my car is reving to about 1700 when I start and stays there. Also, when driving at higher speed it idles at around 2700 when I clutch and stays up there for about 5-10 seconds.

I checked the vacuum hose and it seems snug. I took the filter cover off and put my finger over the mass air flow sensor and it seems to idle normally with it partially covered. I think the engine computer thinks the car is getting more air than it actually is getting.

Also the idle seems to drop when I get to about 40 kph (25 MPH) down to about 2200 or so and again drop back to 1700 when speed lowers to about 20 kph (12 MPH).

The dealer will not do anything unless the check engine light comes on.

Can I do anything or just suck it up?
 

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what did you use to clean up the t-body??

id say that
1. something wasnt properly install back
2. vacum leak
or
3. the cleaner that u used wasnt the proper thing to use
 

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Discussion Starter #5
Used throttle body cleaner from Canadian Tire (Canadian automotive store). Cleaned all the oil that I assume was coming back through the vacuum tube.

I tried playing with the vacuum tube but nothing changed. I will likely have to take it apart and put it back together again.

I did also spray electrical contact cleaner on the MAF sensor but it seems to be reacting to air flow changes.
 

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if it;s reacting to low air flow, what i might suggest is, if you have an air hose, pull out the MAF sensor from your air box, and hold it about three to four inches away from the air line. Spray the air BUT NOT DIRECTLY AT THE MAF SENSOR. if the idle of the vehicle changes when you do this, it means the vehicle is not picking up the right readings at that sensor, and it needs to be replaced.

REMEMBER: point the air line away from the MAF sensor. Direct contact from high pressure air will damage the sensor, so hold it away from the stream of air. The change in air pressure from beside the air stream should trigger it to change it's air fuel mixture. Thus readjusting your idle on the car.
 

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Discussion Starter #7
OK re-tightened everything and changed the factory tube clamps to ring clamps on the vacuum hose.

How about I just blow on the MAF rather than risk damaging it? That is assuming it isn't damaged.
 

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Discussion Starter #8 (Edited)
OK I believe the MAF works fine. Don't know why but it is at least responding.

Heres a theoey: What if the PCV is stuck? How do I fix it? Or is there a PCV?
 

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Discussion Starter #9
OK for anyone that this may happen, after taking it to the dealer (the tech had 40 yrs experience) he couldn't figure it out so called the Canadian head office and had to re-flash the ECM to get it to idle normally again.
 

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OK I believe the MAF works fine. Don't know why but it is at least responding.

Heres a theoey: What if the PCV is stuck? How do I fix it? Or is there a PCV?
There is a PCV system but it does not have a working spring-loaded valve like older cars did. The Ecotecs have metered orifices in the intake manifold that act as a valve -- there is a passageway in the cylinder head to the top of the valve cover; the second part of the PCV system is the hose from the intake to the valve cover. If you take off your valve cover you will find a steel plate that covers the entire valve cover to separate the oil from the crankcase gases.
 

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i had sumtin closed to yours too when i cleaned up my throttle a year and 1/2 ago.... since i had it open (intake off) seems like the timing or the sensor screw up with sumtin (why did they make electronic throttle in cobalts?) I sort of just reset the ECM wit code reader and it worked fine i think thats wut happen then
 

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Discussion Starter #13
Wow really? the problem was with your ecm?
Yeah, well thats what fixed it anyways. First thing they thought of was the vacuum system as well. They scared me for a minute saying they might have to replace the computer. Where I live it is really dry and theres a lot of static in the air. The only thing I can figure is static might have messed things up when handling the MAF and that got back to the ECM. Guess it wouldn't hurt to get a bracelet similar to those used for messing with a home computer and attach it to the engine somewhere or the negative terminal.
 

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Yeah, well thats what fixed it anyways. First thing they thought of was the vacuum system as well. They scared me for a minute saying they might have to replace the computer. Where I live it is really dry and theres a lot of static in the air. The only thing I can figure is static might have messed things up when handling the MAF and that got back to the ECM. Guess it wouldn't hurt to get a bracelet similar to those used for messing with a home computer and attach it to the engine somewhere or the negative terminal.
it's only dry a few weeks out of the year, enough storms roll through Alberta to counteract the dryness
 

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OK for anyone that this may happen, after taking it to the dealer (the tech had 40 yrs experience) he couldn't figure it out so called the Canadian head office and had to re-flash the ECM to get it to idle normally again.
I have had the exact same problem for almost 2 months and have had no success in figuring out what the issue is. Do you think if I just went to the dealer and told them to reflash my ECM that'd do it? I'm wondering if they had to do anything special during the reflash, or if it was a pretty standard procedure. They charge 100 bucks to reflash so I want to make sure it'll work.
 
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