Popping Sound

[Metacom]

Hi All,

I recently changed the fuel pump on my 87 GN with a Delphi FE0115 pump. Since changing the pump, I’ve had an intermediate issue with a popping noise at 1/4 throttle or so and the car failing to accelerate. It has also stalled a couple times when putting it in reverse.

Had a spare known good AC Delco coil pack and ICM I tried and still encountering the same issue.

Anyone know where else I should be looking? Thinking a possible lemon fuel pump?

 

[Chuck Leeper]

A fuel pressure reading may help......

 

[Metacom]

A fuel pressure reading may help......

Sure thing Chuck, I’ll try and get some readings tomorrow.

Just put the gage on the schrader valve located on the fuel rail? Does the car need to be running or just the key turned on?

 

[dynoman]

Car running and if there is no provision to depress the schrader valve in the gauge set-up , remove the core , just watch for fuel spraying from residual pressure .

 

[Chuck Leeper]

To do an accurate assessment, the gauge has to be visible while driving, and the engine under load.
Or, put a sensor in the system and log it with Power Logger.

 

[Metacom]

I ordered a fuel pressure gage that looks like goes straight on the schrader valve. So is measuring fuel pressure not possible with the vehicle in park and on it has to be driven?

 

[dynoman]

It can be checked in park , but that will only give you a base fuel pressure reading . Your problem seems to be under load so you would need to see it while driving and rising 1 to 1 with boost .
42-43 psi vac line off = base fuel pressure and 1 psi of fuel pressure added for every psi of boost .