fuel pump ballast resistor bypass?

I'm having some troubles with the fuel pressure ( I think) not being quite where it should be at idle (my jeep will stall if i slam on the gas when it is still cold, and hesitate before accelerating when warm). Anyways, I was wondering if by passing the fuel pump ballast resistor under the hood by connecting the two wires directly would do any damage. The only reason I am considering doing this is because its a brand new fuel pump and I'm running out of ideas, if bypassing the resistor doesn't help, I guess I'll just replace the brand new pump. Thanks.

Shorting across the ballast won't impact you much (more noise, more heat), it should be fine as a diagnostic or even as a temp-fix... some of the arftermarket pumps arent used to be so far shut-down and may tend to cavatate resulting in crappy flow performance, but...

About the only thing I'd recommend is that when you do short the supply, that you try to keep your tank's fuel level above the pump so that any heat will dissapate


Have you measured pressure at the rail and the functioning of your fuel pressure regulator? How are your injectors doin'?

could be the fuel pressure regulator. did you test the pressure on the fuel rail?

when you put in the new pump, did you replace the fuel filter?

yes you can bypass the ballast resistor

Big DaveXJ said:

I'm having some troubles with the fuel pressure ( I think) not being quite where it should be at idle (my jeep will stall if i slam on the gas when it is still cold, and hesitate before accelerating when warm). Anyways, I was wondering if by passing the fuel pump ballast resistor under the hood by connecting the two wires directly would do any damage. The only reason I am considering doing this is because its a brand new fuel pump and I'm running out of ideas, if bypassing the resistor doesn't help, I guess I'll just replace the brand new pump. Thanks.

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I had this same exact problem in my 90 XJ. all i did was get some B-12 and pull off the throttle body and spray it out scrubbing it with a toothbrush. Once it got all pretty and shiny again i put it back on and all problems were solved. Just don't use your wifes toothbrush without asking her first, I'm still catching hell for that stunt.

How would I test to make sure the fuel pressure regulator is functioning properly?Yes, I replaced the fuel filter when I did the pump. How much resistance should the ballast resistor provide ( so I can check it with an ohm-Meter to rule it out as a problem). Some other weird issues that seem pertinent here: Occasionally when I hit a bump with some good speed (~15mps) the Jeep will stall out, also it is now developing a little trouble starting and the fuel pump is making that whining noise like when it is going bad. Thanks for the help guys. I'll be cleaning out the TB this weekend to see if that helps at all.