P0301 Cylinder 1 Misfire - High Fuel Pressure

[1998SilverGSX]

Hey everyone, this is my first post to be gentle. I've done some searching but I can't find anything substantial to solve/pinpoint my problem.

I am running ND 660CC (flow tested and installed a month ago) with a VR4 fuel pump. The car was running very well a few days ago, until two days ago, when I installed a DNP manifold and VP 2.5 O2 housing. Before this installation, my fuel pressure was around 60 psi. Now, my fuel pressure is off the charts, currently sitting at 92 psi. I am also experience a P0301 error code - cylinder 1 misfire. Also, after the installation, I was overheating. I burped the system, hoping that the overheat was causing the misfire, but the CEL came back after I cleared it.

Now, what I don't understand is how my fuel pressure is so high now? Is this normal for this setup? Also, could this be in any way related to my recent installation, and/or the cause of my CEL - cylinder 1 misfire.

Any help would be greatly appreciated.

Supporting Mods

-Ernie

 

[huafist]

I don't see an AFPR in that list anywhere??

 

[1998SilverGSX]

I was under the impression that with a VR4 fuel pump, I wouldn't need a FPR because this pump would not over run the fuel rail. I could be wrong, but what I heard and read.

Also, I was considering buying a FPR for my fuel system, but after some thought, it still wouldn't explain why my fuel pressure has changed so drastically.

Any other ideas/suggestion what is causing these problems. Thanks again.
-Ernie

 

[river]

you are overrunning your stock FPR, go get a aeromotive FPR and install that and control some of that fuel pressure. your pressure rose so much due to the fact that you are putting a high flow pump and injectors into an otherwise stock fuel system

secondly, your misfire is caused by fouling your plugs. go get some NGK BPR6ES's and put them in along with a set of Accel Thundersport plug wires.

also, it would be a good thing for you to go get a logger or dsmlink.