fuel pressure issue. (new info)

[2002 v6 camaro uncharged]

My fuel gauge died a couple of months ago and I got a new one about a month later It is showing that my fuel pressure is running low.

At idle it is showing 36PSI and if I am driving and just take my foot off the gas without pushing in the clutch the PSI drops to about 32. I thought that maybe this new gauge was just inaccurate but it seems like it getes a little lower as time is going by. I am pretty sure at idle when I first put it in was at 38PSI (cold starts at 41PSI) The longer I drive the lower the Pressure gets. Also, if I shift into a higher gear to soon I think I hear spark knock while accelerating.
Any ideas of what this could be?
My fuel pump and filter were changed in April.

[ August 25, 2005, 06:48 PM: Message edited by: 2002 v6 camaro uncharged ]

[Mighty Thor]

Mine is going down too. Check my previous post. What I did was change my Fuel Filter and it was fine again.

Also check and see if your fuel pump is going too or like SSMS5411 said that a line might be leaking.

Hope this helps.

[Turbo V6 Camaro]

i have never seen my fule PSI go below 44 with the walbro

[2002 v6 camaro uncharged]

Can a fuel filter be clogged after only 5 months and if the walboro was going bad would it be making any noise? Also I was wondering if bad or dirty injectors would cause this? I have 74,000 miles on the original injectors.

Here is a little series of events that have led to this point.

First, I was running 6 PSI powerdyne with the stock fuel pump and the fixed ratio vortech FMU that came with the RK Sport kit. Then the car started running like crap and my stock fuel pump died so I had the Walboro put in as well as a new fuel filter and upped the boost to 9 PSI.

After this when I went into boost the fuel pressure jumped pegged at a 100PSI and the car would bog. Shortly after my Cat went bad so I figured the car was running way to rich so I bought a Cartech Adjustable FMU and while I was waiting for it to come in my Fuel pressure gauge took a dump.

The new FMU came in and I installed it but had know idea what the fuel pressure was until my new gauge came in which is where I am at now.

Oh yea, and all those problems with the rough idle and driving like crap that I was fighting with for months just ended up being a ripped diaphram on my by-pass valve for the super charger. Wich was a little frustrating because of all the money I spent and the headaches I got changing other things trying to find the problem. The worst part is the by-pass valve was only 5 months old.

[ August 25, 2005, 09:32 AM: Message edited by: 2002 v6 camaro uncharged ]

[2002 v6 camaro uncharged]

Well, I did a test when I left work. I turned the key and the pressure went to 40 then about 10 seconds later the pressure started dropping. It was not a smooth drop, it went to 39 held for a second then to about 37.5 and so on all the way to 30. It probably would have kept going down but I turned off the key in disgust. You get one problem fixed and then another problem occurs.

[Turbo V6 Camaro]

Originally posted by 2002 v6 camaro uncharged:
Well, I did a test when I left work. I turned the key and the pressure went to 40 then about 10 seconds later the pressure started dropping. It was not a smooth drop, it went to 39 held for a second then to about 37.5 and so on all the way to 30. It probably would have kept going down but I turned off the key in disgust. You get one problem fixed and then another problem occurs.

you have a leak

[2002 v6 camaro uncharged]

Confused now, after I drove to work and did the test the fuel pressure climbed to 35, slowly rose to 39.5 and held.

[jessica2112]

sounds like the problems I had. I just got #36 injectors, trashed the FMU and that was the end of it. Still have stock pump, and it's holding up quite well.

[Turbo V6 Camaro]

Originally posted by jessica2112:
sounds like the problems I had. I just got #36 injectors, trashed the FMU and that was the end of it. Still have stock pump, and it's holding up quite well.

i had 57# injectors on my stock pump and it held 12 psi and running under 11.0 on hte WB O2 but the PSI would drop 1-2 psi