uneekcrx

i was at a light today and my car starting idling real low...kinda like it was bogging from getting too much fuel...so i pulled over and checked and my fuel pressure guage was reading around 90psi at idle....and it wasbarely running....i don't know i checked all vac. lines for possible leaks....and nothing....so i turned off the car and started it again and it runs perfect...what the hell does that mean?

Flamenco-T

yes it is possible...I had the same problems, what you want to do is try to by pass the FMU and see if your fuel pressure is still high..at idle..
if not, then you know the FMU sticking..just replace it

uneekcrx

what would cause it to stick...is there anyhting else i could do ?...i'll be changing to an 8:1 fmu disc real soo because of my bigger injectors i'm putting in....would that fix the problem or it is actually something inside the fmu causing it to stick?

PureTeg420

sounds like the fmu is definatly sticking. You can just open it up and fix the problem....assuming it is the fmu that is causing the high fuel pressures

uneekcrx

open it up where the disc goes in at or open it up more where the other allen screws are..when i opened it up to look at the disc it doesn't seem to look like much i don't know what to look for to know what to fix

CovertFI

i remember reading on the vortec website that removing the six screws is ok but if you remove the 4 screws at the bottom, that is bad. said some think like you have to get it put back together from the factory or some thing. not sure, but check their website.

uneekcrx

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niedejb

I had to completely disassemble mine since one of the 1/4 npt fittings were loose. I read that on the Vortech site but didnt buy it. It works fine now with no leaks.

Theres a large diameter plunger thats pushed on by the discs and the membrane in the top. As the plunger is pushed down, the fuel is restricted. You should be able to disassemble/clean it and get it to work. Probably trash in there keeping it pushed down.

Also if you dont have good vacuum, theres nothing to pull the plunger back up. How's the vacuum level?

Ri5e

Same here, the Vortech fMU, they didn't tighten one of the fittings tight enough. So I had to hack it off and put on my own fitting. Damn those bastards.