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Discussion Starter #1
Yo!

So the other day I cleaned my throttle body in order to clear a TPS code I was throwing (P0121). I took it off the car and cleaned it with TB cleaner. Covered up the connection port while I was spraying. It did clear that code. However, it seems that now my idle is kinda odd. It's been about 3 days now and hasn't "learned" much, or gotten better. I've looked at other threads and some people seem to have the same problem. Hoping I don't have to go get it flashed.

Starting up the car, it revs higher on initial fire, up to about 2000 and then back down to 800 for idle. It'll stay at 800 if I sit there. The problem is when I hit the gas. If I rev the car, it descends down to about 1200, hovers there, and then goes down to normal idle. Graph Below.

RPM graph after two revs - Imgur

It does this when I'm driving as well. Any time I let off the gas, it will hover at high rpms. When I'm driving it doesn't go below 1200 or so until I come to a full stop. Then it settles down. Sometimes the rpms are high enough that I can't coast. I have to hit the brake to slow down. This seems to be hurting my gas mileage too.

Other problems...When decelerating, sometimes the car will "buck" or hesistate, seemlingly where it would downshift itself (if it does that, it's an automatic). You can see the sharp valleys in the graph below for that. It's oddly sharp, almost seems like a lost connection. This doesn't happen all the time. But ONLY on deceleration.

RPM bucking when decelerating - Imgur

And this is of the Throttle Position Sensor. The three humps are where the bucks happen, but they spike UP here. So that's weird.

RPM dropping, TPS graph - Imgur

Check these out, see if you guys are familiar with this problem. I've checked the tightness of my 4 bolts on the throttle body, and the connections are all tight on the wiring. I don't suspect MAF or anything, because I didn't do anything do it. I'm guessing cleaning the TB just made more air available and my engine doesn't know how to handle it, idk. See what you guys think. Thanks! Really don't want to pay to have it reflashed. I shouldn't have to do that after cleaning the TB.
 

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Firstly you are not suppose to spray the throttle body cleaner in the throttle body, you're suppose to spray on a rag and wipe the throttle body clean to avoid washing the butterfly grease off of the shaft. If you spray directly in the throttle body then this solvent candidate make it's way to the TPS. Mine you I don't believe this is your problem yet. What you are experiencing is an intake leak. Maybe you tighten you throttle body to tight and broke the gasket. You have an intake leak my friend.
 

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Discussion Starter #3
Ahh. That's weird, I read a bunch of posts about cleaning the throttle body, and none of them said not to spray in there, especially if you have it pulled off the car. I watched some videos and they did it too. I did spray a lot though to get it soaked in. Is there something else I can spray in there to oil the shaft?

I'll take a look at the gasket, it's possible that I overtightened. I'll have to find the torque specs for that when I put it back on. I have looked into that and the symptoms of a TB leak didn't quite match up though. They said rough idle i think, and I wouldn't necessarilly call mine rough. How positive are you based on my symptoms?
 

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I've cleaned my throttle body twice and it did the same thing. I would say you don't necessarily have a leak, but try an idle relearn if you have access to a scan tool. I'm not sure if disconnecting the battery for a little will set it back to factory settings.
 

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Discussion Starter #5
Yeah I tried doing the thing where you put the key to on and let it sit there for a few minutes. Will try a battery reset in a few days if it persists. I cleared another CEL when I went to get these graphs too, that didn't do anything. But I will check the gasket too, I had to yank on the TB to get it off the first time.
 

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Discussion Starter #6
Bump and edit. I've come up with that the car only drops rpms aggresively when it seems to be shifting down. It doesn't do it any other case. So if I decelerate to a light, at the point where it would shift down to the next lowest gear, the rpms drop instantaneously. Like the opposite of rev-matching lol. Currently letting my battery connections sit together for a while and see if that helps. Checked my TB gasket, looks perfect. Retorqued the 4 nuts to spec-ish as well (it's really hard to feel 7 ft lbs on a torque wrench haha). We'll see how it goes.
 

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You should not touch both leads together for more than 10 seconds or you will drain the memory backed up CPUs. You could kill your RCDLR.
 

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Discussion Starter #8
I had to look up RCDLR, and I have manual locks so I'm good. But everything was fine. Didn't fix the idle too much, but it doesn't seem to be bucking anymore. Witg the idle, i may just have been used to lower airflow from a dirty throttle body. It settles down at lights but it's still high when in gear and I let off the gas.
 
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