TwistedTahoe
Newbie
I’ve got a 99 Tahoe 5.7L. I have put on 2x New Carquest pumps (P/N #988748CQ) I did one new pump, had the issue described in the title. I chalked it up to being a bad part and just slapped on a pump from a junkyard. All was fine until that blew up doing donuts (stupid i know). I figured I’d try the new Carquest pump and to my surprise, it has the same issue (as described in the title). I had transferred the sensor that hangs off the back onto all 3 pumps from the original so it can’t be that either. Any help with diagnosing this would be appreciated. I’m about to gut the spring and plunger from where the fitting screws into the pump itself.