z32 na Not running properly

[Mikco]

Hello! So I have this z32 n/a and it's not running as it should be. It seems to be running rich (consumption is waaay too big) and sparking plugs are quite dark. On half throttle it runs and accelerates as it should, but when accelerating on full throttle it doesnt run properly. Also when pressing clutch while driving the engine often shuts down..

So what I've done so far; Sparking plugs changed (gap 1, 0mm) , ignition coils measured, injectors measured, maf cleaned, ignition timing checked (now at 15 degrees), changed new ptu (old one was broken, car ran on 5 cyl), engine temperature sensor changed, fuel pressure regulator changed, searched for vacuum leaks... also the timing belt has been replaced, and now the belt should be on correct position (the problem was already before the change), fuel filter replaced..

I have also tested plugging both lambdas off and test-drived, the car didnt run any better...maybe even little bit worse. All electrical connections on the engine bay have been opened and checked (the connectors are in bad condition)..

I would really appreciate if I got some help on this issue. Every advice are welcome!

[elwesso]

Welcome to NICO.

I'd be checking the MAF a little more, maybe find a used one (preferred known good) and see if that fixes it. It sounds kind of MAF-like IMO. Also check the connector and make sure it's not corroded or anything. A bad MAF can cause it to run way rich and intermittently stall.

Has the car always run like this since you've had it? Have you done anything since the car was running normally?

[Mikco]

Thanks for posting!

The connection of Maf is in good condition. I would try different maf if I had one somewhere near..

I bought this car crashed on the front corner and it hasnt been running properly ever, I don't know how well it ran before the accident..

[Ziggy1621]

Running rich could definitely be the O2 sensor. Run the o2 sensor test at the bottom of this http://www.nicoclub.com/archives/nissan ... ostic.html

And welcome to Nico!

[Mikco]

Here`s a little update.

The big issue at the moment is the idle. The car is running quite well, but the idle is ~1800rpm (when the engine is warm) and the engine shuts down when pressing clutch while driving. I`ve cleaned and changed FICD and AAC and they both were fine. Also air regulator has been checked. Turning the idle screw makes idle drop only a little bit. The throttle bodies are fully closed for sure.

TPS output is now 0.41v on idle. When TPS output is adjusted to less than 0.4v the engine idle drops to the right RPM but when driving with this setup the car doesn`t acceletare well and still the engine shuts down when pressing clutch.

I`ve tried searching for vacuum leaks but haven`t found any. It seems that nearly all the air that goes to the engine on idle goes through the pipe that leads to the IAA (when pressing this hose the engine speed drops dramatically).

Again, I would appreciate some tips or advice! I`m starting to feel that whatever is the cause of this is the reason for all other problems..

[Ziggy1621]

have you done an ecu and o2 test?

[Mikco]

I checked for error codes and there was code 34 (detonation sensor). Could this be the cause for car running poorly and rich? I have bought already a resistor (1 000k Ohm) which I`ll asseble and try asap..

[Ziggy1621]

Not necessarily rich, but poor.. yes. Continue that ECU test and run the test on the 02 Sensors. There are times when the O2 sensor will not throw a code 53 but still not function correctly during the test at 2500 rpm.