Rough Idle 2007 S

[JDMMX5]

Hello everyone, so juts recently got my car back from the body shop. And about a day later the car had some rough idling issues, then the battery completely crapped out. So went a got a new one today, but still same issue rough idle. Car idles around 650-700 but drives completely fine once going. No CEL or anything like that. Bad ECU?

[silver04rollas]

Do you hear any ticking sounds at all??

Generally the 1ZZ engine is quite a rough engine so some vibrations are expected especially around a very low 650 - 700 rpm idle speed. However, if the idle is too rough and vibrations are very pronounced then it might be an issue.

[hardtopte72]

If the battery was unplugged for too long or discharged completely the ECU may have been reset. I would bet money you have a dirty throttle body and the ECU is relearning it and just has not yet accounted for it. I would first clean the throttle body. It should go away on its own even if you don't.

[boberic]

Originally Posted by JDMMX5

Hello everyone, so juts recently got my car back from the body shop. And about a day later the car had some rough idling issues, then the battery completely crapped out. So went a got a new one today, but still same issue rough idle. Car idles around 650-700 but drives completely fine once going. No CEL or anything like that. Bad ECU?

Was that issue present before? Is the car just now experiencing cold for the first time in a while? What exactly did the body shop do?

There's lots of things a body shop might do wrong if they had to replace the radiator, for instance, but general paint work/fender/glass replacement etc probably not.

How old was the battery? If not very old, perhaps you have an alternator problem or lack of good contact in one of the positive or one of the many ground connections.

There are some vacuum hoses near the battery that I could see somebody wanting to remove to replace the battery and then forget to put back on (or put back onto the wrong connector).

[JDMMX5]

Originally Posted by silver04rollas

Do you hear any ticking sounds at all??

Generally the 1ZZ engine is quite a rough engine so some vibrations are expected especially around a very low 650 - 700 rpm idle speed. However, if the idle is too rough and vibrations are very pronounced then it might be an issue.

No ticking sounds. Idle is actually about 400-500

[JDMMX5]

Originally Posted by hardtopte72

If the battery was unplugged for too long or discharged completely the ECU may have been reset. I would bet money you have a dirty throttle body and the ECU is relearning it and just has not yet accounted for it. I would first clean the throttle body. It should go away on its own even if you don't.

Im not sure if the battery was disconnected at the shop or not, but the battery was pretty much done when i got it back. But recently the problem went away and just came back. So i will try reseting the ecu again and clean out the throttle body. Thanks

[JDMMX5]

Originally Posted by boberic

Was that issue present before? Is the car just now experiencing cold for the first time in a while? What exactly did the body shop do?

There's lots of things a body shop might do wrong if they had to replace the radiator, for instance, but general paint work/fender/glass replacement etc probably not.

How old was the battery? If not very old, perhaps you have an alternator problem or lack of good contact in one of the positive or one of the many ground connections.

There are some vacuum hoses near the battery that I could see somebody wanting to remove to replace the battery and then forget to put back on (or put back onto the wrong connector).

Never had the issue before, but the shop didnt replace or do anything in the engine bay the car was damaged on the quarter panel side. The battery was the original so it was bound to go soon. Dont beleive its alternator just put a new battery and seems to be holding a charge fine. But i will recheck connections and vacuum lines

[juicedz]

Originally Posted by JDMMX5

Never had the issue before, but the shop didnt replace or do anything in the engine bay the car was damaged on the quarter panel side. The battery was the original so it was bound to go soon. Dont beleive its alternator just put a new battery and seems to be holding a charge fine. But i will recheck connections and vacuum lines

Good luck! It's been nothing but a nightmare for me to track down and no one can give me a clear answer to what the problem is.