1990z32+2

ok im gonna pull the codes check fuel pressure and check for leaks but its been raining th past few days will post update when the weather clears up and i check.

1990z32+2

Sorry for the long delay. im not trying to waste you time just time but just ogt a job and frustrated. so my detonation sensor is bypassed and the tap i was hoping was a lifter is now a lock and i have 3 misfires and believe its in safe mode. believe its a valve tap. on z1motorsports if you look at stage 1 or 0 head for z32 it notes that valves are made of "inferior" metal and i believe thats the culprit. i repaced fuel filter and checked pressure and relay and thats fine. vacum tested my lines and came back fine.

zracer70

Hi, I was wondering if you ever solved your engine issues. I became the somewhat proud owner of a 91 300zx 2+2 last October and I can tell you that these engines are a nightmare. I have owned a 76 280z, 81 280zx, 83 280zxt, and a 88 300zx, so I consider myself pretty knowledgeable when it come to troubleshooting EFI issues. However, this car is trying to drive me insane. I am hunting a rough idle and hesitation issue and although I have failed completely at that, I have learned a great deal about these horrible, horrible engines in the process. I think every z32 owner needs to start with a few basic modifications:

1. Delete the AIV system, it is useless.
2. Relocate the PTU.
3. Reroute or delete the PCV system, it is really badly designed and allows a lot of oil into the intake system.
4. Delete the plenum coolant lines.
5. While you have the plenum off, go ahead and grind off any tabs that get in the way of removing the fuel injectors while the plenum is installed.
6. Clean the crap out of all the old rectangle-style electrical connectors and reinstall them with dielectric grease. 99% of them will be covered in greenish corrosion. Replace the ones that are brittle and falling apart.
7. Now you can actually get down to the business of troubleshooting!!!