2007 Lucerne fuel pum acting up again
 

Back in march I had an issue with the fuel pump running to long off and on, a new relay fixed the problem. Now two months later it is starting to happen again! What else in the system can cause this? Note the hold down bracket have so it can not come in contact with the relay. Can a faulty regulator cause what is happening? I hate intermittent issues:rad

Oddly enough it did it Friday afternoon and again on Saturday, stopped Sunday and so far today. Sunday afternoon I pulled the seat, pulled the relay which has bright clean contact pins and show no signs of anything. Will see if and when it pops up again!

Thanks for the reply

No problem. Curious how this turns out.

Had to re visit this post! I think I may have stumbled onto something interesting about the pump cycling. First a quick run down, new relay, brackets trimmed as per diagrams so it does have the proper clearance. Ok the interesting find, the pump only does long cycles when there is someone sitting in the right rear seat. This has happened both times I had someone back there, leads me to it seems as if the relay may be affected not by pressure but by metal being in closer proximity. I pulled the seat this morning there is absolutely no sign of any contact. Now I am thinking GM found the same result hence the much shorter relay which I will buy and report back.

Phil

Wow, good sleuthing!