GTP fuel pressure question.Please read!

[edy figueroa]

Hello everyone,

I just need advise since i was looking at the fuel pressure of my 97 GTP and is reading 67!! at the rail gauge i installed.I am running the resistor bypass.Also i disconnected the vacuum line from the regulator and jumps to 72!!! Pump is the factory one and no hotwire upgrades.

Is this a FPR issue or what can it be? I think is too much.What do you guys think??

Ed.

[BNaylor]

To start if you are running the resistor bypass that should be corrected by getting a new fuel pump resistor. Your fuel pump is running in high speed mode and may burn out. The readings are higher than normal and may cause a rich trim mode to the fuel injection system.

What is the reading at fuel pump prime which is ignition to on only with engine not running? What brand fuel pressure tester gauge is it?

[edy figueroa]

Originally Posted by bnaylor

To start if you are running the resistor bypass that should be corrected by getting a new fuel pump resistor. Your fuel pump is running in high speed mode and may burn out. The readings are higher than normal and may cause a rich trim mode to the fuel injection system.

What is the reading at fuel pump prime which is ignition to on only with engine not running? What brand fuel pressure tester gauge is it?

Thanks for the reply,
Codes are:
P0300,P1380,P1645.
Pump prime is 50 engine off. The gauge is a Marshall Shockproof gauge installed permanently on the fuel rail.Also i am not getting more than 5 pounds of boost but dont know if is it related yet.

[BNaylor]

Wow that is a weird combination of DTCs.

Pump prime reading is good and within specs. Low or high fuel pressure could cause the random misfire DTC P0300 so if you still have the fuel pump resistor bypassed then get that taken care of and the P0300 issue may get resolved.

For DTC P1380 are you having any known ABS issues? ABS light on or running with bad wheel sensors. This DTC triggers when the electronic brake and traction control module (EBTCM) has detected a malfunction which will not allow the EBTCM module to transmit rough road data to the PCM module. An ABS capable scanner should be used to further diagnose this issue.

The reason for low boost is the P1645 DTC. The PCM module has detected a malfunction with the boost control solenoid circuit. Possibility of wiring between the PCM module and boost control solenoid, bad boost control solenoid or PCM module.

[edy figueroa]

Originally Posted by bnaylor

Wow that is a weird combination of DTCs.

Pump prime reading is good and within specs. Low or high fuel pressure could cause the random misfire DTC P0300 so if you still have the fuel pump resistor bypassed then get that taken care of and the P0300 issue may get resolved.

For DTC P1380 are you having any known ABS issues? ABS light on or running with bad wheel sensors. This DTC triggers when the electronic brake and traction control module (EBTCM) has detected a malfunction which will not allow the EBTCM module to transmit rough road data to the PCM module. An ABS capable scanner should be used to further diagnose this issue.

The reason for low boost is the P1645 DTC. The PCM module has detected a malfunction with the boost control solenoid circuit. Possibility of wiring between the PCM module and boost control solenoid, bad boost control solenoid or PCM module.

I fixed the bypass and now is back to 58-60 psi running.Changed the solenoid and BBV along with a GM maf sensor and checked for leaks and broken cables again along with a bigger s/c tensioner pulley and gatorback belt,STILL only 4-5 pounds of boost?!
Also getting the P0300 and 1645 codes.I noticed that i am getting missfires at cylinder 2,4 reading from the Interceptor scan gauge.Got new 104's plugs..I miss my boost!! Will check my DHP PCM connections.
Also 0 KR on boost..

[edy figueroa]

Still looking for the BOOST problem...
thanks for the suggestions guys.

Any other help will be appreciatted.
Ed.

[edy figueroa]

Originally Posted by edy figueroa

Still looking for the BOOST problem...
thanks for the suggestions guys.

Any other help will be appreciatted.
Ed.

SOLVED!

Back to 9psi.I bypassed the solenoid by taking out the hose from the bbv to the solenoid and the other hose coming out from the solenoid.I guess it is an electrical issue.