[Joshinator99]

Originally Posted by towerfab

I definitely have some sort of serious issue with my rail pressure. 800 psi is
where it was at idle before the recent work, slightly higher with a very light load. I was running the 2650, lt4 low and high side with the dsx aux pump. After the cam and port installation I immediately noticed the rail pressure at idle fluctuating from 1100 to 2000 psi. I also noticed crazy fluctuations at a steady light to moderate load, say like 60-70 mph with no throttle fluctuation. I see the pressure at 1800 plus then suddenly drops to 1300, at which time I feel the car miss. I also notice the air fuel ratio go from 14-15 to over the top, 28+. While all this is happening I'm keeping an eye on the low side and it doesnt seem to be dropping, it stays pretty steady around 60 psi. I get p0300 among other 02 sensor codes. Seems like it takes about 10 to 15 minutes of driving before it starts acting up. I'm having some serious doubts about the installers skills. He thinks there is an electrical issue due to the fact that the car had a previous right front strike. My plan is to get it to another tech and tuner to hopefully figure it out.

If your O2 sensor situation is wonky it will definitely throw the car off since it uses them to adjust the air to fuel mixture once they’re warmed up. Given that your car seems to run better cold and acts crazy after “10 to 15 minutes” of driving it leads me to believe you have oxygen sensor issues or exhaust leaks. I would fix those before chasing anything else.