Originally Posted by
upstate240sx pulled all the plugs and they are all fouled black, running pig rich. i vacuum tested the fpr and it holds vacuum (unable to test its correlation with fuel pressure) but im assuming thats good. Also because at idle im not running rich (dont hear popping in the exhaust or smell excessive fuel). i also ordered a consult tool to assist with setting timing among other things. exhaust manifold gasket will be arriving today. after clearing the codes yesterday the p0170 appeared again which indicates a fuel trim malfunction. i replaced the maf after searching through a few threads and that seemed to be a first step to look at. prior to checking the plugs i was expecting maybe an injector was stuck open and i would find just one fouled plug, not all.
Good luck with this man. I had this problem with my NX. I've done a million things to it to fix the problem, and changing the knock sensor seemed to help the most. Of course I had a knock code though. I also regrounded, and checked every thing possible. I had bypassed the inhibit clutch relay to get mine to start (I ran a hot wire to the starter from the IGN switch), and once I reconnected everything the correct way it ran way better. I also just read in another thread Calum posted in that the ECU needs to be grounded (The metal shell itself to the chassis). I didn't know this, and I've had it just hanging in the pass floor for a month or so, because I've been pulling codes trying to track my issues down. I even went as far as testing all of the wires on the ECU harness, and they all checked out. Well after all I've done it's gotten much better, and yesterday I put the ECU back in place and bolted down. That seemed to help as well. It seems grounding is a big issue with all our cars pretty much. I also would like to ask if you ordered a genuine consult, and how much? I've wanted one, but when I checked before they were expensive. It would be a handy tool to have.