How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Tim Mohr Your Own Question
Tim Mohr
Category: Pontiac
Satisfied Customers: 15600
Type Your Pontiac Question Here...
Tim Mohr is online now
A new question is answered every 9 seconds

high speed..module..constantly run my fuel pump at high pressure

Customer Question

Can i hard wire my 2 speed fuel pump to run at a constant high speed? I heard that one of the wires that goes to the fuel pump is a variable ground controlled by a module. If I directly ground out the wire it will constantly run my fuel pump at high pressure. This is for a supercharged 3800. I had a mechanic put in three fuel pumps a few years ago and after the third one, It stopped stalling out on me. Now, it is getting could and it is starting to do the same thing again. I have no idea where the 2 speed fuel pump module is or what color wire to ground. The car has barely 90K on it and I have had since new and it is in good shape.
Submitted: 6 years ago.
Category: Pontiac
Expert:  Tim Mohr replied 6 years ago.
Hi, my name is XXXXX XXXXX do not have a 2 speed fuel pump in them, who told you they did/ they are a single speed pump, with the power controlled by the fuel pump relay, and a single ground that goes straight to the body.
Customer: replied 6 years ago.
I guess that is why I could never find a fuel pump module that ran the fuel pump! The mechanic that replaced the fuel pump three times told me that it had a module that controlled he fuel pump and varied the fuel pump speed by resistance in the negative lead to the fuel pump. It kinda made sence to me at the time. It only does this in the winter time when it gets cold out. The car will simply stall. It will start sometimes, and then not at all. I have replaced the fuel relay a long time ago thinking that somehow the cold might affect it. I have put a fuel pressure gauge on the shraider valve to see the fuel pressure. It is either zero, or really low. I NEVER take my car to a mechanic but had to in the dead of winter 2 years ago for this problem. I also pinched off the return line from the pressure regulator to see if it made a difference, but it didn't. The car has never been run out of fuel, and it dosen't matter if the fuel tank if full or low.
Expert:  Tim Mohr replied 6 years ago.
if you had zero or real low pressure, and you pinched off the return and it stayed the same, then the fuel pump is bad, we only use delphi pumps in these, most parts houses sell the Airtex pumps and we see alot of problems with the airtex, napa sells a delphi pump, see if you can get one from them, they are excellent pumps and are OEM,Tim