Super-dee-dooper rich GLHT!

[Clay]

Ive been working on the GLHT w/ TII conversion. It has a stage II GLHS LM w/ 2 piece, and daytona rad/ic, stock fuel pump, and stock TII injectors.

The car has always had a rich smell to it, ie raw fuel smell from exhaust when running. I checked the fuel pressure yesterday with the vacuum line on and it was 50-ish PSI, which Im thinking is high w/ vacuum on it.

when I first get into it I get a nice puff of BLACK (read: Diesel) smoke as well.

thoughts? can a fuel pressure regulator fail by giving to much pressure??

[black86glhs]

If the FPR diaphram gets a hole in it, it will cause your type of problem, yes. Pull off the vac hose when its running and see if gas comes out. It shouldn't.

[cordes]

A leaky line to the map will cause it to run rich at idle etc. too.

[Clay]

ok, Ill check for fuel while its running, and check the lines. All the vacuum lines are new, so Im not suspecting that problem, but who knows!

[Marcus86GLHS]

50 psi fuel pressure should be while the vacuum line is disconnected and plugged off not connected...i'd also try to borrow a wideband to confirm the smell-o-meter.

[Clay]

This is one of the reasons I kind of wished I had bought an LM1 instead of the LC1. ;)

[Clay]

ok, i checked all the vacuum lines, and there were a couple of questionable ones, so I just replaced them.

Next I checked fuel pressure. Seems pretty high to me. With the vacuum line connected fuel pressure was 48 - 50 psi, with the vacuum line disconnected fuel pressure was ~58 psi. I need to get a gauge w/ vacuum on the car so I can see what that is. No fuel came out of the regulator when I unplugged the line, and I even watched it for a bit.

also, weird thing, when I had the FPR line disconnected I heard a vacuum leak, thinking it was the FPR vacuum line, I plugged it back in, but I still heard the noise. I found the noise when I put my finger on the injector plug of the #2 injector. That seemed to make it quite down a bit. The weird thing is I could twist the #2 injector around a bit (this is the one right next to the FPR), and the noise would lessen, and almost go away. twist it back, and the noise returned. Im wondering what the WTF that could be?!?!

[Turbodave]

Maybe a bad o-ring between the injector and the intake allowing a vacuum leak? That's almost what it sounds like.

[Clay]

thats what Im thinking, only thing I can think of anyway.

[cordes]

Regardless of whether it is related to the problem, I would replace those injector O-rings ASAP. Nothing good can come of that for sure.

[Clay]

no worries, I will. But, its leaking from the manifold side, not the fuel rail side (IF thats whats leaking ;) )

[Clay]

OK, just for my reference, what is the fuel pressure suppose to be with the vacuum line unhooked?

I still think its rich, but want to double check. Ive swapped FPR and Im still getting the same pressures, so my next thing to look at is the return line itself.

thanks,
clay

[cordes]

55PSI static pressure.

[86Shelby]

Are you using the same injectors? One might be leaking a little bit causing it to constantly run rich.

[Clay]

yeah, all the injectors are the same, and they are old. Thats on my list of things to replace actually. I wish I had a way to test them myself, but I dont have a stand.