bill: thanks i repared the ground wire behind drivers tire. wire was clean no rust just broke off the bolt when removing it. checked the one on the pass side removed was also clean sanded a little added some dieelectric grease and replaced. this did not let the fuel pump run when turning on the key. checked fuel pump fuse ok unplugged fuel pump @ left tank. removed fuel pump fuse. put fuse back in replugged in fuel pump at tank. turn on key pump would run. started car ran aprox 2 minutes and stopped.at this point here are the codes.
10 pcm (2) p1626h p1571h
28 tcs (1) c1242h
38 rtd no comm
40 bcm (2) b 0432h c b2527h
60 ipc no codes
80 radio (1) u1016h
99 hvac no codes
ao ldcm no codes
a1 rdcm no codes
a6 scm no comm
bo rfa no codes
this problem started about 3 months ago, car stopped with 1/4 tank gas. added gas 5 gal it started. checked with gm they had a service bulletin you used the julian codes on each tank as to what to replace put in a new fuel gauge and strainer assy in left tank. gas back in started and ran good. filled tank full and ran down to 1/2 and car quit. gauge still read 1/2. turn on key and pump would run. so removed pump from left side tank m/t but took 7 gal plus from right tank. so replaced pump on right tank seemed like the check valve was plugged. back together 2 gal gas and started good to station filled up . 20 miles and quit again. fuel pump would not run. i have got the car to run two times by pulling fuse from fuel pump unplugging the wire at fuel pump waiting a few minutes and fuse back in then wire back on pump . but only runs a couple minutes. good anti theft system ha ha where should i look from here. 1997 thanks george

 

Hopefully, you only used dielectric grease as a surface treatment, and not as an interface between the terminal and the grounding point.....as the grease is an insulator...not a conductor.

Does this mean you replaced the pump in the left tank? Since this is a repeatable failure, it should easy to isolate. During the times when the pump does not run, what have you checked?

Ground at the pump connector, 12 volts at pump connector, 12 volts/ground at the fuel pump relay, etc.

When the pump does not run, have you tried jumping the relay socket to make the pump run continuously?

The P1626 is not comforting either.

 

removed the ground it is clean just grease on outer part.
replace the jet pump in the right tank
ground at pump connector ckecks ok
no 12v at pump connector
20 amp fuel pump fuse under hood ok
relay has 12.14 volts both sides this is the two sides that are toward the pass fender.
the other side of relay ground on the front hole and nothing on the back hole
2 days ago the car started and i let it run for 45 minutes.
today started ran 5 or less then stopped.
jumping the relay did not start the pump.

 

Ok, so if you are saying you jumped 30 to 87 per the picture below, and did not have 12 volts at the fuel pump connector.....you have a wiring problem between the fuse box and the fuel pump connector.

 

thanks i feel like we are getting somewhere.
I show 5 connectors between relay and pump is any certain one been a problem or just start from one end and go till i find the problem. since relay does work ok then bcm and pcm is talking to each other??

 

In the event of a VATS issue, the PCM will disable the fuel injectors, not the fuel pump. The PCM keeps the fuel pump enabled provided it receives a crankshaft sensor input(that's why it only stays on for 2 seconds if you turn the key on, but do not start).

I can't speak to anyone of the connections as being prone to failure.

 

lucky is there a way to check the crankshaft sensor, could this be a problem instead of maybe a broken wire in the harness?

 

If you lost the crankshaft sensor input to the PCM, you would have no spark, and you would not have 12 volts at "86"..of the relay socket per the photo.

Plain and simple.....jumping 30 and 87 will make the fuel pump run continuously.....so if you have no power at the fuel pump connector, there is a wiring issue.

 

i will go into the wirning tomorrow and let you know. thank you very much. Ill sleep better tonight knowing what to try tomorrow.

 

me on the head. i was checking the hot wire at the fuel pump turn on the key get down and put my meter on it no power. then went to the other side of car under by the right side of transmission to a harness connector from the front which feeds power to both fuel tanks this time had my wife turn on key while i checked had power there. so bad wire from there over no checked the left side when she turned on the key had power but only for 2 seconds then off i understand it works this way if the pump does not run so unplugged it would not run. plugged back in and still pump would not run so hit it with a hammer to see if stuck well ran fine. looks like i need to replace the pump. where might be the best place to find a pump.
thanks lucky for all your help.

 

Bill, what do you recommend using to jump the relay? a fused connector? what size fuse?

Okay, imadummy; too many posts open at the same time...LUCKY, what do you recommend?

 

Yeah Bill......what to you recommend?

 

No problem. Hoping you just didn't get lucky here. I would use the jumper, and see how repeatable your results are.....i.e. pump stops and tapping on the tank gets it going. When the pump stops, shake down the wiring harness and connector to make sure you don't have a funky connection.

 

Oh, and do I need to have the key in ACC/ON to make this work?

 

No sweat....some folks would rather hear from the Master

Yes, you must have the key in the "on" position. Since the circuit you are jumpering is fed by fuse #13, a "fused jumper" is not required; however, I would use a minimum of 12 gauge wire.

 

lucky i have played with the wires over the last two months and never helped. pump has ran for the last two days. i don't drive this car much it set from may till oct every year. where would you recomend getting a new pump. is the delco mu 1215 ok? really appreciate all your help. thanks george