I have a supercharged z28 with a stock fuel pump and a Vortech t-rex inline pump. The past few weeks one of the pumps has been making a lot of whining noise especially at idle, it whines louder than normal and sometimes whines laud and quiet loud and quiet and my fuel pressure guage drops during these whines by a few psi. Is this a sign of one of my pumps going out?

Thanks all!

 

Since you can see a drop in pressure with the sound of the whine, that is definitely not good. I would not go WOT with the car until you get it repaired. If it were mine, I might not even drive it until it was repaired... might leave you stranded and that would not be good

 

Mine does that sometimes as well, a bit annoying really. Haven't had a chance to document changes in pressure though. You might want to check your fpr also, could be that as well- if it changes the pressure it could change the load on the pump... well, that's my theory anyways. I don't know if it's correct or not, just thought it could be a possibility.

 

Hmm, I did try going wot yesterday just to try to resolve another problem I'm having, watching the fuel pressure, it built up to almost 45 psi at around 5k rpm. the pressure seems to go up like it used to, only at idle it seems to kind of "surge" when the whining happens, also while driving the whine seems to go away (but it may be that the noise of the exhaust is making it not heard...)

 

do your rpms seem to have a pulse to them under steady throttle. I mean does it rev smooth or king of waiver under throttle.

 

The rpms go up and down smoothly when i rev the car and the car appears to drive very well, no drivability problems....