Jimmybevis

I need a little help taking the fuel pressure on my AC6 Z51.

I hooked up the tester to the end of the fuel rail, but not getting any readings. Is there something else I need to do to get a good number? I also tried to check the fuel line that goes into the rail but cant get the connector off. It looks like a push/pull connection but no luck (Yes I did take the connector lock off first).

I had a new fuel pump on it a few months ago so that shouldnt be the problem.
Thanks
Jim

ClothSeats

To disconnect the fuel line, you need a special, but inexpensive tool. Search on Youtube for videos that show how to disconnect the fuel line. Forgive me if this sounds dumb, but you didn't say that the engine was running when you tried to measure the pressure with your gauge on the fuel rail. The engine must be running, or in "on" mode so the fuel pump is running in order to measure fuel pressure.

Jimmybevis

The car is in a crank/no run status. When I tried to measure the pressure if was trying to crank.
I would hate it the fuel pump was bad. I just had a new one installed not long ago. I have no idea how long
GM warranties the Pump.

Thanks for your input.

torquetube

Are you saying it cranks (for like 10 seconds or so) but won't start? That would be consistent with no fuel pressure.

Check the fuel pump relay, and the fuel pump relay terminals in the connector under the fuse box.

Drift Vette

Did you ever get this fixed? I am having no fuel pressure at cranking either.

Jimmybevis

Yes the car is fixed. After spending over $6000 on pumps and other parts it turned out to be an electrical issue. I would check that first.

FYI: Dont make the same mistake I made by taking the car to a dealer. I went through three chevy dealers who couldnt help me. I found a small shop that specializes in foreign cars and they had the thing fixed within three days.

Jim

C5 Diag

Doesn’t surprise me a dealership couldn’t diagnose this…can’t remember the last time I read on the Forum a dealership diagnosed a car correctly !!..what was the electrical issue ???

C5 Diag

Do you own a 12 volt incandescent test light ??…that is all you need to diagnose this !!…does your fuel pressure gauge have a pin in the end of the hose that will push open the Schrader valve ??…do you hear the pump turn on for 2 seconds with ignition on ??

Dano523

What gauge, since you may have to pull the schrader valve if the gauge does not have a way of opening it in the fuel rail port, or is pushing the valve deep enough to open it.