Idles rough coming to stop

[aarons129]

Just recently purchased a 2011 PPV, ran like crap when I got. So far I have replaced plugs and wires, new air filter and cleaned the throttle body. Runs a whole lot better now but when I am coming to a stop the RPMs drop below 500 and shudders a bit then levels off then the RPMs bounce around until it settles, 30 seconds or so. I am not sure what else to do besides replacing the coil packs maybe. Currently running Premium. Any advice is much appreciated.

 

[OR VietVet]

Welcome to the forum from Oregon.

Any CEL? Last time mine did that, I had a bad O2 sensor.

 

[aarons129]

Thank You,

No CELs present. Even before I started replacing parts.

 

[Fless]

Need to look at it with a scanner that will do live data. What are the short- and long-term fuel trims at warm idle?

After it warms up a few minutes does it go into Closed Loop? Are the O2 sensors moving up and down?

 

[aarons129]

I will look into that tomorrow. Thanks

 

[opfor2]

check the coolant sensor by the power steering pump. they have been known to cause idle issues if bad.