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DISCUSSION => Engine + Driveline => Topic started by: enildeR on June 09, 2006, 10:13:51 PM

Title: Fuel Pressure
Post by: enildeR on June 09, 2006, 10:13:51 PM

What is our fuel pressure supposed to be at idle and WOT?

When you shut off the engine, does the pressure drop back to zero?
For the longest time, after I installed a fuel pressure gauge, the pressure would always be between 30-40psi when the engine was off.

After I had my injectors ultrasonically cleaned and put the intake all back together, the fuel pressure dropped to zero after I turned the engine off. It just struck me as odd because I had been used to seeing it stay around 35psi.

I did clean the TB with brake cleaner, so maybe I cleaned gunk out of the hole that feeds the line going to the FPR?? *shrug*

Thanks for any info in advance.


Bryan

Title: Fuel Pressure
Post by: asubimmer on June 10, 2006, 12:30:10 AM

should be around 43ish at idle, the pressure shouldn't drop fast when you turn off the car.  It should take some time.  Maybe when you put everything back in something didn't sealed right?

Title: Fuel Pressure
Post by: enildeR on June 10, 2006, 05:17:03 AM

Quote from: asubimmer

should be around 43ish at idle, the pressure shouldn't drop fast when you turn off the car.  It should take some time.  Maybe when you put everything back in something didn't sealed right?

That was a thought, but I couldn't smell any gas vapors. I'll check more in the morning.

Title: Leak down.
Post by: D. Clay on June 10, 2006, 11:48:06 AM

Agree with asubimmer's post. Mine leak down slowly. Building the pressure back up is the fuel pump sound when you turn on the key. My pump runs for a second or two first thing in the morning but not at all if the car has only sat a short time - less than 5 minutes. Any more than that and the pump comes on when the key is moved to the ON position to build pressure back up. With the motor running I can't tell if the pump is running or not. I have a noisy little car.