I got my stillen adjustable fuel pressure regualtor installed the other day, now the problem is the adjustment screw seems to only be able to adjust the pressure 4-5psi, the pressure is at 48psi at idle and when under acceletation it will dip down to 41psi and then shoot back up and peg at a constant 56psi till I let off. I have no clue what is wrong, do these take time to break in, or did I just do something wrong?

 

I think it's better if you can find the original Stillen instruction. I belive the Stillen piece is a fuel pressure raiser. I don't think it suppose to replace the OEM FPR. I could be wrong.

 

However, if it is the FPR, I would say there may be a vacuum leak. I have dealt with this for the past 2 months, and I just found the leak. Now, everything is fine.

 

I had forgotten about this thread, well to update, it was a simple fix it turns out that the instructions I was given were wrong and I had the lines mixed up, so basically the pressure wasn't being regulated. I t works great now and it is very easy to adjust if needed I am very happy with it.

 

Good to hear. So, you had the in/out fuel lines mixed up? Believe it or not, I had that same problem when I installed my SARD FPR. The instructions were in Japanese and of course, offered no assistance to my install lol......