Hello and help!!
No One
Joined: Mar 2011
Posts: 1,574
Likes: 3
Check the wiring at the relays. These were a common problem spot. Check the inertia switch, make sure it is not tripped. It should be located on the driver's side, to the right of the brake pedal, if you are laying on your back looking up. Look for a little red button.
The EEC (ECM) Power relay does send power to the coil of the Fuel pump relay when the key is turned on.
The Computer will then ground the other side of the fuel pump relays coil to close its contacts. The computer will ground this fuel pump relay for one second when the key is turned on and then again when the engine is cranking or running. To bypass the computer just ground pin #6 of the EEC self-test plug and turn on the key.
The power for the fuel pump relays contact common comes from a fuse link at the starter solenoid battery side. The output contact goes to the inertia switch.
The EEC (ECM) Power relay does send power to the coil of the Fuel pump relay when the key is turned on.
The Computer will then ground the other side of the fuel pump relays coil to close its contacts. The computer will ground this fuel pump relay for one second when the key is turned on and then again when the engine is cranking or running. To bypass the computer just ground pin #6 of the EEC self-test plug and turn on the key.
The power for the fuel pump relays contact common comes from a fuse link at the starter solenoid battery side. The output contact goes to the inertia switch.
Last edited by AuroraZero; Jan 7, 2012 at 07:24 PM. Reason: aded image and more explanation
Thread Starter
Member
Joined: Jan 2012
Posts: 82
Likes: 0
From: Louisville, ky
Check the wiring at the relays. These were a common problem spot. Check the inertia switch, make sure it is not tripped. It should be located on the driver's side, to the right of the brake pedal, if you are laying on your back looking up. Look for a little red button.
The EEC (ECM) Power relay does send power to the coil of the Fuel pump relay when the key is turned on.
The Computer will then ground the other side of the fuel pump relays coil to close its contacts. The computer will ground this fuel pump relay for one second when the key is turned on and then again when the engine is cranking or running. To bypass the computer just ground pin #6 of the EEC self-test plug and turn on the key.
The power for the fuel pump relays contact common comes from a fuse link at the starter solenoid battery side. The output contact goes to the inertia switch.
The EEC (ECM) Power relay does send power to the coil of the Fuel pump relay when the key is turned on.
The Computer will then ground the other side of the fuel pump relays coil to close its contacts. The computer will ground this fuel pump relay for one second when the key is turned on and then again when the engine is cranking or running. To bypass the computer just ground pin #6 of the EEC self-test plug and turn on the key.
The power for the fuel pump relays contact common comes from a fuse link at the starter solenoid battery side. The output contact goes to the inertia switch.
Big Rig Driver
Joined: Mar 2011
Posts: 247
Likes: 1
From: Fort Nelson, BC
The thicker wire off the battery negative goes down to a holder and then to the block. Mine was corroded bad at that holder part. I just cut it off there and put a new end on it and mounted it to a bolt on the alt bracket.
No One
Joined: Mar 2011
Posts: 1,574
Likes: 3
Well I would suggest running the small wire down and see if it may be broken, or the connector down there might be messed up but you probably already have done all that. So I am all out ideas, sorry I could not help you.
I will not tell you if you have a bad ecm or not. I will not tell anyone that over the internet without testing things myself. I look for the usual things that go bad on things over time. Again I am sorry I was not more assistance to you maybe someone else here can be of more help.
I will not tell you if you have a bad ecm or not. I will not tell anyone that over the internet without testing things myself. I look for the usual things that go bad on things over time. Again I am sorry I was not more assistance to you maybe someone else here can be of more help.
Senior Member
Joined: Feb 2009
Posts: 709
Likes: 31
From: Grants Pass, OR
^^ can't find any diagnostic procedures, I've done all I know to do and then some. I've got a wiring diagram its the little orange ground from the back of the motor. At this point I'm starting to think I somehow fried the ecm... What kills power to the pumps AND injector pulse?
The injector wires and pump relays are pretty much connected directly to the ECM.
Last edited by klricks; Jan 8, 2012 at 10:08 AM.
Senior Member
Joined: Aug 2010
Posts: 2,669
Likes: 116
From: Long Beach, CA
Just to help clarify so we don't keep going into deeper problems. Did the engine run well before pulling it. If so odds are pretty high something was not re connected properly. Use the obd to check for faults. Next take accurate measurements. Check fuel rail pressure with a gauge. Check voltage at the pumps, fuses, tank switch and relays. Make sure its the proper voltage, not just a test light. That will tell you if you have a voltage drop. You can test the EEC at a good parts store or auto shop. But start simple and be thorough.