Fuel pressure rise rate low...
 

Hey all,

I'm having an issue where it appears that my fuel pressure rise rate is low. The onset pressure is set properly to where I want (ballpark at least) where a slight increase will just start to run rich. I can tell because the engine runs just slightly rougher with little "pops" out the exhaust between gears. Normal driving is fine, but more pressure on the pedal and I'll start to get some detonation.

I've replaced the pump, almost sure that perhaps the ten yr. old pump was dying a slow death. No change afterwards. Now I have a new OEM filter ready to go in. But before I replace that...

Question: Doesn't the fuel flow through the filter from the bottom up and then out through the top, therefore, couldn't the possible clog/bottleneck be downstream after the filter? Also, I have an in-hood fuel gauge which does display a correct pressure reading. It is attached on the TOP of the filter, so wouldn't a clogged filter give me a lower reading?

What do you guys think? Thanks for reading.

Adub

Re: Fuel pressure rise rate low...
 

More food for thought: It had just occured to me that achieving proper idle fuel pressure with a clogged filter is one thing, while building pressure fast enough under driving conditions with a clogged filter is entirely something else? Hmmm...seems like a sound theory.

Any thoughts or suggestions are appreciated,

A