weird idling problems
 

Hey guys,

So i just recently purchased my Z and everything has been going fine. But yesterday a slight problem popped up regarding high rev idling. When the car
gets into neutral the rpm hang at around 1500. This is after 15 min of driving. my sport mode (syncro rev match) doesnt seem to affect it either as it occurs when it is off as well.. Its a 6mt btw. One time while it was hanging at a stop i just slightly tapped the accelerator and the rpm dropped to normal 650. I have NO idea whats going on. Can someone help?

Thanks

Does the car have any mods? Has it ever been tuned?

So im not sure if it has ever been tuned but it does have a Stillen CBE. Whats weird is that it wasnt having this issue for the first week and half.

How many miles? Try cleaning the MAFs and throttle bodies. Did you get a CEL?

about 48,2xx miles. No CEL however.. I was thinking it might have something to do with the MAF sensors but wasnt sure

I was gonna ask, do you think it could be an airfilter issue?

When in doubt, change 'em out. Air filters are easy to access and aren't that expensive.

If that doesn't line things out, I'd try TerribleONE's clean-the-MAFs suggestion. Another cheap (can of MAF cleaner) and easy (two small bolts per MAF, no gasket to replace) job.

If the MAFs are visibly dirty it'd be a good idea to clean the TBs but that's a harder job that may require some recalibration if you mess up.

Cool, appreciate both your help

If you clean your TBs don't unplug them. I did mine and all my idle issues went away.
Use a lot of rags under them. I rotated intake down with rags everywhere. Spray cleaner and use a lot of q tips to get it all out.

Unplugging them is when you require recal. It isn't a big deal and I know somewhere on this forum there are detailed instructions on how to do it. I chose the not unplugging method. Worked great for me. Also clean the MAP sensor as well.

okay thanks. Did you happen to have any similar issue? or did you clean them for another issue/maintenance?

I had TB problems, my rpm kept dropping, this issue is different i remember some one from this forum had this problem, until they reset the ecu. Ahh and check ur TB connections could be loose. GL OP.

Just clean everything first. Take the TB's off, it's really not that hard. If the idle isn't fixed just google TB reset procedure. What it sounds like though is a air leak. Check your hoses for cracks or leaks. I'm betting your plastic elbows behind the MAF sensors in the post MAF tube might be cracked like they do on most.