Sticking accel pump

[Clone TIE Pilot]

My car (in my sig) developed a rich problem with the A/F mixture dwell stuck at 50 degrees (the computer going lean to offset the rich problem). While checking my TPS which read .94 volts at idle and 4.44 volts at WOT, I saw the Accelerator pump was sticking. When I opened the throttle and let it snap back to idle, the accelerator pump very slowly returns back out. Should the acceleator pump snap right back up when the throttle is returned to idle? If it is sticking, would that cause a rich mixture?

 

[techg8]

it should immediately follow the pump lever back up to the top position. If its not, it is likely there is a problem with the pump cup.

The pump sticking in the bore would not cause a constant rich condition.

 

[Clone TIE Pilot]

If the pump is sticking, then the other soft parts like the float or needle tip may be bad too. 😢 I had this carb rebuilt by Sean Murphy and it worked great for the last 3 years, guess he didn't use the best seals or nothing lasts long with E10.

 

[techg8]

nothing lasts long with E10.

thats spot on.

 

[Clone TIE Pilot]

I have the accel pump out and not sure if it is swollen or not. Even with the airhorn off, the pump is slow to return after being depressed.

 

[techg8]

check the pump bore for white oxidation or texture.

might need a polish with some finefine paper.

its apart anyhow, put a new pump in there see how it goes.