I have a 91 maxima SE with a M/T that I have brought back to life, kinda... New plugs, oil, filter, air filter, cleaned the MAF and runs as good with it plugged in as without (at idle of course), distributor cap and rotor good, wires good, KS tested good, temp sensor test good, o2 sensor replaced, etc. Now the issues. When driving, it is a little rough and is really bad between 2400-3000 RPMs. and when it (the car) is warm, the car will not start for a few hrs unless i pull the fuel pump fuse (long story on how I figured that out). There is proper fuel pressure and the pump works fine. I replaced the fuel filter also. I did the injector listen test with a screwdriver and all sound good. I decided to pull the plug wires while running to see if it makes a difference. When i pulled plug wires from cyl 4, 5 and 6 it would bog down and run like crap (even worse then it already does). When I pull 1, 2 and 3, no change. nothing... I pulled the plugs and they are firing fine! I tested all the wires again, and they are all good! the plugs from 1, 2 and 3 are also black, soot covered, and the soot does not cover the tip of the electrode or the ground tab where it sparks to (the hook part of the plug)


I heard something about the crank and cam position sensors going bad? where are they on this car? any other ideas? Please?

Thanks,
Adam

 

Bump..... Please.....

 

Replace spark plug wires for cylinders 1, 2 and 3. You are losing spark/current to the plugs.

You can double check if any of them are arcing by increasing throttle by hand w/the hood open. Best to do in a dark garage or at night. You should see current jumping from the wire to the valve cover or cylinder head.

I'd recommend a new set of OEM wires...around $80 from Courtesy Nissan.

 

already did that, even tried swapping wires from cylinders and nothing.... the wires are fine. The plugs are getting spark. The bare spots on them where the spark travels shows that as well

 

have you ohm tested your injectors?

 

Well if you are getting sparks on both sides, then most likely fuel related OR the firing sequence is out for that side. double check the distributor and the wiring. check the injectors and wiring to see if in proper order