P2188 - rough idle for about 5 miles

[phueltank]

Hello all,

I've read through a lot of great posts on the P2188 OBDII code, and have already taken care of some of the simpler issues. Before I go digging in to finding a vaccuum leak, cleaning the ETM, or changing plugs and coils, I'm hoping my specific symptoms might help point me to a good starting point.

Here's what I have:
- at initial startup, car runs fine for about 60 seconds until it comes off of its initial high cold idle.
- once the engine is warm enough to come off the start-up idle, it hunts. RPM fluctuates between 400-1600. Generally, the RPM drops to the point where it almost stalls, then the engine revs up. As long as I'm on the gas, it's fine. When I let off, either at a stop or coasting, it goes back to hunting. It will also occassionally stall out at a stop.
- once the engine is fully warm, the problem goes away.

I've already taken care of the air filter, checked the air ducting, P44'd the fuel system, and changed the oil. Any help prioritizing next steps woudl be helpful.

Thanks!

Frank

[phueltank]

Apparently, I didn't give the changes enough time to work. The surging went away today, as did the engine code. Fingers crossed.

[hughsrj]

I have this exact code (and only this code) with my recently tuned-up 2007 XC70. Did your CEL stay off permanently? Did you per chance also have the PCV system or timing belt maintenance done just prior to this issue? I just had both and car ran fine before the service and now throws this code!

[Legofan]

Hello all,

I've read through a lot of great posts on the P2188 OBDII code, and have already taken care of some of the simpler issues. Before I go digging in to finding a vaccuum leak, cleaning the ETM, or changing plugs and coils, I'm hoping my specific symptoms might help point me to a good starting point.

Here's what I have:
- at initial startup, car runs fine for about 60 seconds until it comes off of its initial high cold idle.
- once the engine is warm enough to come off the start-up idle, it hunts. RPM fluctuates between 400-1600. Generally, the RPM drops to the point where it almost stalls, then the engine revs up. As long as I'm on the gas, it's fine. When I let off, either at a stop or coasting, it goes back to hunting. It will also occassionally stall out at a stop.
- once the engine is fully warm, the problem goes away.

I've already taken care of the air filter, checked the air ducting, P44'd the fuel system, and changed the oil. Any help prioritizing next steps woudl be helpful.

Thanks!

Frank

Did you have this fixed? What was the resolution?