Low RPM's when idling issue

[Hooggaan]

Hey guys just a quick question if anyone can help me at all. My cars been acting very strange lately. When starting up my car the RPM's will rise to 1kish for a few seconds then dip to around 4-500 and the cab will start shaking. It will do that for a couple seconds then RPM's will rise to 1-2k again then dip back to 4-500 again. After searching this forum for an answer to work off of, I've had no luck. I took of the IAC and cleaned it with carb cleaner a little bit and put it back on and started it and no luck. Can anyone help at all?

 

[rs2k]

Does it happen with your AC on and off?

Do you have a lit check engine light?

 

[jremington59]

Does it do it after it's warmed up?

 

[deweyville65]

You cleaned the IAC valve. Did you check the voltage readings with a digital volt meter? Get yourself a manual with the voltage specs, and go from there. Will tell you if the ECU is telling the IAC to change idle speeds, or you may have a faulty IAC valve. BASIC things first.

 

[Hooggaan]

Does it happen with your AC on and off?

Do you have a lit check engine light?

Yes it happens either with ac on or off, and recently a check engine light came on after the issue.

 

[Hooggaan]

Does it do it after it's warmed up?

It seems to go away after it warms up from driving. I havent tried to just start it and let ot warm up by itself yet.

 

[rs2k]

What code caused the check engine that? That will probably tell us what the problem is.

 

[drdoom]

Please if could fill in your vehicle specs in your profile , or at least which engine you have. But to me it sounds like a hose breach of some type.