Crank, no start?

LITTLETHING

MEMBER
2011 BUICK LUCERNE
3.6L
V6
2WD
AUTOMATIC
145,000 MILES

Started having issues with power when going uphill. It would accelerate fine if I put my foot into it, but between 1.3-2 RPMs, the car struggles. Took it to the shop, who told me there were no issues. Scanned it, no codes. Fuel relay eventually burnt out. Replaced the relay, it lasted a day, burnt out again. Third relay burnt out; new relay did not allow the car to start. It would crank, but not start. I purchased and installed a new fuel pump and relay, but the car still will not start, only crank. Verified with multimeter that there is power going through the relay, relay is engaging, and fuse box is good. The car still is not throwing any codes, simply will not start.

Edit: Car has spark, but there is no power going to the pump.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi,

If you jump pins 87 and 30, does the pump turn on? If it doesn't, is the fuel pump fuse, fuse 1, good? See pic below

Let me know. Additionally, confirm there is power to pin 86 and pin 85 provides a ground path. See pic below.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Keep in mind, you indicate the prior relay was failing. There could be a short in the gray wire that powers the pump. That should cause fuse 1 to fail, but it may take long enough for it to fail to cause the relay to go bad.

Let me know what you find.

Joe

See pic below.

Image (Click to make bigger)