So I bought a fuel pressure gauge before I replaced the fuel pump to decide what was wrong. I replaced the pump and now my pressure is 100 PSI at idle. Turn the key it's goes up to 80, then 100 after it's started. Do you guys think it's the FPR? I wouldn't know which one to buy to replace it, I don't know what year the LT1 intake and fuel rails came off of to put on my TPI. Are all the LT1 FPR the same? It's on the drivers side fuel rail.

Thanks

 

How do you know the gauge is accurate ?
What pump are you using?

If they have the front crossover tube ; 92/93
If not 94 - 97

If you have $$$
http://www.summitracing.com/parts/ae...make/chevrolet

 

I just bought the gauge at the auto store.

Granatelli 255LPH I just bought from Jegs

 

OK, so I just replaced the fuel pressure regulator, had to take it in b/c the regulators had the mount on the opposite side, so they found one that had it on the side I need, hooked it up, still reading 92 PSI, but when I hit the purge valve on the side of the gauge, it goes down to 45ish. It starts up fine, drives fine for a minute or two, and then backfires and stumbles like it's not getting fuel, but might be getting too much and flooding it out, like it's stumbling. I'm about to give up...

 

Are you sure nothing is clogged in the fuel rail or return line, That would cause your fuel pressure to be high. And that high of fuel pressure would be dumping a lot of fuel in the combustion chamber, Check a spark plug and see if its gas soaked.

 

What's the easiest way to check to see if either of those are clogged?

I'll check the plugs tomorrow. Can I check them without it running for a while, or should I check them after I have had the run running for a little bit?

 

Longer you leave it the more chance any fuel will dry off the plug so you won't be able to tell anything.

 

OK, so I ran it for a little bit, then pulled #3 plug. It wasn't soaked in gas, but it was very black and it did smell like gas. I just changed the plugs a couple of months ago and I bet I've only put maybe like 5-10 miles on it just driving it around the block and starting it every now and then in the garage, I don't think they should be this black.

Also, it's way out of time, like high and it's jumping around from like 12 - 16, and when I try to move the distributor cap, I can't move it anymore to bring it down b/c the cap hits the back of the intake, has anyone ever heard of this or know how to fix it?

 

I'm using NGK TR55 plugs.

 

Ok, will the pressure read high if I'm checking it with the vacuum line still connected?

 

No it reads lower with vacuum line connected.

I doubt your gauge, as most pumps are internally regulated to limit them to approx. 80psi. Also stock injectors lock about 85psi, shutting off fuel. If aftermarket then they still likely keep working.

Is there is a chance you pinched the return line replacing the pump?