Hello everyone, just joined the forum and have an 07 350z. I have recently installed a ported upper and lower intake manifold, Z1 intakes, shorty headers, test pipes and HKS exhaust. Ended up getting the idle surge problem which was weird because I didn’t clean, unplug or touch the butterflies during this job. Either way I replaced the throttle bodies with a used OEM set and (I think) fixed the issue.

I am thinking of adding some cams next but have a question about the idle because I live in NY and have to pass the plug-in OBDII inspection. I know if my idle is a bit higher than normal that I will throw a CEL for high idle, which will cause me to fail inspection.

My question is, does anyone have personal experience with cams on the HR motor and whether or not they will keep idle low enough to not throw the CEL? I know the tune will be the key to keeping it under control, but I want to be sure before I do it. Most posts I see about cams are from states where you don’t need to pass an inspection of this type, so there is very little information.

Any information would be awesome. Thanks!

 

did you tune it after you installed all those parts?

 

Not yet, just got it back together but will be doing a mail order Uprev tune from Z1 at some point this winter. In case you were wondering, the surging idle had nothing to do with the modifications providing more air flow. I have called Z1 and talked to others with similar mods and not having a tune won’t cause the idle surge. I must have accidentally hit the butterfly or something, damn things are so sensitive apparently.

 

you are definitely running lean though, and yeah they are super sensitive. you will more than likely need to replace it

 

Yeah, already did. The new set works well with the idle relearn so I’m pretty sure that works. Just looking into my next set of mods, any thoughts on the cam idle?