I have a 2010 HHR LT with the 2.4L and over 99,000 miles...it threw the P0011 code yesterday so I replaced the intake and exhaust variable timing solenoids....I also changed the spark plugs.....put a new air hose on it because the old one fell apart......car is still lunging at idle.....any suggestions?

 

Welcome!

First; did you remember to plug the MAF back in after the air filter change?

Are there any codes now?

Dirty throttle body can cause an uneven idle.

 

plugged MAF back in no engine light on now either

 

Do you mean that the idle was bad before you did the work?

Then I would start by checking the connectors to the VVT valves and the MAF. Then clean the throttle body. You have to remove the air cleaner for that anyway. Use throttle body cleaner, disconnect the battery negative cable and don't force the butterfly.

Bad new VVT valves have been heard of.

 

It was idling bad before the work, yes, still is. So clean the throttle body with cleaner. Do you recommend running a bottle of injector cleaner through also?

 

Won't hurt.

 

Just to stress Don's warning: don't force the butterfly - the gears are fragile and are easily broken.

You should read this thread (the WHOLE thread) regarding cleaning the throttle body:
https://www.chevyhhr.net/forums/main...leaning-48936/

Post #5 in that thread is apparently the safest way to clean it.