Rev/fuel issue

AUSTIN5432W33

MEMBER
2003 PONTIAC GRAND AM
3.4L
V6
2WD
AUTOMATIC
134,892 MILES

My car is having two issues where it will start after cranking for a while and giving it some throttle and then once it is idling when I go to rev it the engine wont go past 2,000 rpm's. So I checked fuel pressure and it had 42 at prime and 46-48 while running. So since fuel pressure was good I pulled one spark plug from the front of the motor and one from the back and both were lean (burnt white on the tips?). The back was worse than the front so I thought maybe clogged injectors sense it had good fuel pressure. I got some sea foam and ran it through the intake and the gas and it did nothing. I would like to not tear apart the whole motor to diagnose this issue so if anyone has had the same issue and found the fix or has an idea of what could be wrong lmk. I thought about the fuel pressure regulator but if that was bad it would not have good pressure at the rail? I do not know if you have any suggestions. Thank you, Austin

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

Seafoam does nothing. You added to the intake and it has nothing to do with the injectors. If you want to clean the injectors, you have to disable the fuel pump and run injector cleaner through the fuel rail and run the engine on the cleaner until all used up. there is no additive that has any effect on cleaning injectors.

As far as your issue, your fuel pressure is too low. I attached the actual spec for you. You are better than 10 pounds low.

You need a fuel pump.

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Roy

FUEL SENDER ASSEMBLY REPLACEMENT

REMOVAL PROCEDURE

CAUTION: In order to reduce the risk of fire and personal injury that may result from a fuel leak, always replace the fuel sender gasket when reinstalling the fuel sender assembly.

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1. Remove the fuel tank (4).
2. Disconnect the wiring harness from the fuel sender and the fuel tank pressure sensor.
3. Rotate the retaining ring (1) while pressing down on the fuel sender assembly.

NOTE: The modular fuel sender assembly may spring up from its position. When removing the modular assembly from the fuel tank, be aware that the reservoir bucket is full of fuel. Tip the modular assembly slightly during removal to avoid damage to the float. Use a shop towel to absorb any leakage.

4. Remove the fuel sender assembly.

IMPORTANT: Carefully discard the reservoir fuel into an approved container.

INSTALLATION PROCEDURE

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1. Install the new seal on the fuel tank (4).
2. Align the fuel pipes parallel with the mark on the fuel tank.
3. Slowly apply pressure to the top of the spring loaded sender until the sender aligns flush with the retainer on tank.
4. Install the retaining ring (1).

IMPORTANT: Be sure that the retaining ring is fully seated within the tab slots.

5. Connect the wiring harness to the fuel sender and the fuel tank pressure sensor.
6. Install the fuel tank.

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