Nissan 370Z Forum - View Single Post - Another Supercharger Idle problem thread

NissanTracker · 07-13-2020, 07:24 PM

Hey, Seb is doing me a solid and helping me on my idle issue. It is definitely something with the Z, not tuner related.

I believe these issues are all connected, but can't figure it out. I experienced very similar behavior on the on the stock A-W Stillen setup. I am also seeing this on the A-A kit. Pulling my hair out... almost 2 years with these idle issues.

Z never had idle problems before the supercharger install at 50K miles. Has 60K now. I did the install myself. I'm on the mid-experienced level "mechanics" wise. Full lift at home, had multiple projects in the past.

1) On cold start, sits at 900-950 with no issue. When things start to heat up, after some long driving, idle goes above 1,100-1,200 and can't seem to get it down.

2) When I put the clutch down while rolling to a stop, the idle surges between 950-1200. When I finally do stop, it takes a bit to come down.

3) If I free rev, as the revs come down, stops at 1,500-2K and "blurps" (stops, momentary rise, then falls). I feel this is related to above

Attached some VIDS:

High HOT idle:
https://drive.google.com/file/d/1rzc...ew?usp=sharing

Idle Surge while rolling to stop:
https://drive.google.com/file/d/1rs8...ew?usp=sharing

Descending Idle "blurp":
https://drive.google.com/file/d/1tnO...ew?usp=sharing

THINGS DONE SO FAR:

Boost leak done and what was found was addressed. Tried idle relearn but when it's hot, I can't complete because it is high.

Leakdown test ~8%.

Also, I went through some threads and some mention that the A-A kit "Deletes" the PCV. Is the actual PCV fitting replaced with a straight through fitting and then vented to atmosphere? I kept my PCV on but just vented to atmosphere.

Throttle-bodies were replaced with new ones

Supporting mods:

350z HR Nismo (MAF Tuning w/UPREV)
Uprev GT MAFs
A-A kit with 1.5" recirc Tial (on a filter)
Stock clutch/flywheel
Motordyne TDX
Stock Cats
9lb pulley (seeing almost 10psi)
Venting PCV to atmosphere through a mishimoto catch can
ID1050X injectors
Walbro 255 fuel pump(modified in-tank regulator)
Mishimoto T-stat
OEM 370z plugs (1+ step colder for 350zHR, gapped .032)

07-13-2020, 07:24 PM	#1 (permalink)
NissanTracker Track Member Join Date: Jun 2016 Location: Massachusetts Posts: 724 Drives: 07' Nismo, 14' Nismo Rep Power: 29262	Another Supercharger Idle problem thread \| Starting to get desperate Hey, Seb is doing me a solid and helping me on my idle issue. It is definitely something with the Z, not tuner related. I believe these issues are all connected, but can't figure it out. I experienced very similar behavior on the on the stock A-W Stillen setup. I am also seeing this on the A-A kit. Pulling my hair out... almost 2 years with these idle issues. Z never had idle problems before the supercharger install at 50K miles. Has 60K now. I did the install myself. I'm on the mid-experienced level "mechanics" wise. Full lift at home, had multiple projects in the past. 1) On cold start, sits at 900-950 with no issue. When things start to heat up, after some long driving, idle goes above 1,100-1,200 and can't seem to get it down. 2) When I put the clutch down while rolling to a stop, the idle surges between 950-1200. When I finally do stop, it takes a bit to come down. 3) If I free rev, as the revs come down, stops at 1,500-2K and "blurps" (stops, momentary rise, then falls). I feel this is related to above Attached some VIDS: High HOT idle: https://drive.google.com/file/d/1rzc...ew?usp=sharing Idle Surge while rolling to stop: https://drive.google.com/file/d/1rs8...ew?usp=sharing Descending Idle "blurp": https://drive.google.com/file/d/1tnO...ew?usp=sharing THINGS DONE SO FAR: Boost leak done and what was found was addressed. Tried idle relearn but when it's hot, I can't complete because it is high. Leakdown test ~8%. Also, I went through some threads and some mention that the A-A kit "Deletes" the PCV. Is the actual PCV fitting replaced with a straight through fitting and then vented to atmosphere? I kept my PCV on but just vented to atmosphere. Throttle-bodies were replaced with new ones Supporting mods: 350z HR Nismo (MAF Tuning w/UPREV) Uprev GT MAFs A-A kit with 1.5" recirc Tial (on a filter) Stock clutch/flywheel Motordyne TDX Stock Cats 9lb pulley (seeing almost 10psi) Venting PCV to atmosphere through a mishimoto catch can ID1050X injectors Walbro 255 fuel pump(modified in-tank regulator) Mishimoto T-stat OEM 370z plugs (1+ step colder for 350zHR, gapped .032) Last edited by NissanTracker; 07-14-2020 at 07:51 PM.