i have a 96 cherokee and for a little bit now I’ve been getting a cel for a misfire on cylinder 1. Checked for spark, compression. Both seemed good. When checking operating fuel pressure it was good as well -50psi range. I decided to do another fuel pressure test today and noticed while bleeding the air out of the gauge, air continuously kept coming out. When I turned the engine off, fuel pressure dropped to 0 in less than 5 minutes. Tried clamping the fuel line (back behind the filter to isolate if it was coming from the pump or not) and it held fuel pressure a little longer but still went down to about 27 psi until I let go of the clamp and then pressure immediately dropped to 0. I’m pretty sure this is a check valve/pump problem. Would this really cause cylinder 1 to completely misfire though?