I recently through in the NGK Irdium's without gapping them and shortly there after in threw off a lean code. Went back gapped them myself to what the factory suggests (.044), reinstalled them, and the code cleared. And now just this morning it went off again. WTF. Im gonna regap them to .039 and see what happens. Running a stock pulley, however got the ZZP CAI, mid-length header/downpipe combo under the hood. I might also just need a tune. Ideas?

 

Factory gap in my 2007 manual calls for 0.039.

My plugs were actually gapped at 0.035 from the factory upoun inspection.

0.044 and even 0.039 is too large a gap for a blown car. Drop it to 0.035.

The lean code is from the zzp intake, not the plugs fyi.

 

The zzp intake is larger than the stock intake. If u check there website it should say u need a tune. At least it use to say.
I think they offer a pretuned pcm just for there intake.
U might as well grab a stage 2 pulley or 3.1 pulley and some s2 injectors and then tune it.

 

stock factory ac/delco plugs set at .032. manual states 0.035 setting for cobalt ss 2009. i set iridium ix plugs which were 1 step colder at 0.35. now high speed acceleration feels slower .is the gap setting or the colder plug the problem? my car has a k&n typhoon cold air intake,3 " kahn muffler and exhaust and a superchip tune.

 

 

Factory SS/SC intake is 3" fyi. The only thing larger on the zzp intake is the flared inlet section for that monster air filter they include.

But that's all it takes to through air flow & fuel trim parameters off, but I know you already know that Trevor.

 

i changed the gap of the recently installed ngk iridum ix 1 step colder plugs in my 09 cobalt ss from 0.035 to 0.032 .the 0.035 gap setting slowed down high speed acceleration but now the 0.032 gap seems to have corrected that problem.over all i really don't see any improvement with a colder plug. i have a superchip tune,a hahn 3 inch catback and muffler exhaust and a k&N typhoon intake .

 

Stock plugs are best for the SS/TC.

 

i listened to staged07ss and removed the ngk iridium ix ltr61x-11 plugs and replaced them with with the stock acdelco 41-108 stock plugs, gaped at 0.032 plugs and my 09 cobalt ss runs faster and smother than with the ngk plugs.

 

I run NGK BKR7E gapped at whatever the 2007 owners manual says. 3" pulley 15psi never an issue

 

Does anyone know if there is a service manual online that i can download ? Im changing spark plug wire spark plugs, a new motor mount, and a transmission filter.