Background:
I had a low oil pressure situation that wiped out some bearings. Changing the rod bearings didn't fix the issue so I got a low mileage (about 147,000) from a 1997 FZJ80 to put in while I rebuild the original motor. Since the motor was on a stand I figured I would do the head gasket and re-seal the motor as preventative maintenance. While the head was off I had it completely rebuilt.
After pulling the original motor I swapped the accessories and manifolds on to the 1997 due to the minor changes throughout the years. I got everything installed back in the vehicle and now can't get it to start.
The issue:
I believe it is an electrical issue somewhere because I've got no spark. When the key is on the check engine light (CEL) doesn't illuminate at all (if I recall correctly it was working prior to the motor swap). Based on what I've read since the CEL doesn't illuminate that means I've got no power to the ECU (or is it ECM?) so that is the first place to start. I pulled the glove box back out and checked the connectors. I found that the four connectors plugged in to the ECU were fine but I had forgotten one of the white connectors. I plugged it in and thought for sure it would fire up but there was no change.
My fusible link appeared to be good but I changed it out anyway and have 12v at the other end of it. I've read many "No Start" threads and @Tools R Us will ask if there is power at the B+ terminal of the diagnostic connector on the firewall. I do have approximate battery voltage at that terminal. I think that means that the EFI circuit is good but am not certain.
I swapped the EFI relay with the power window one from the driver side kick panel and it didn't change anything. I can also feel the relay click when the key is turned. While it was out I tested for power at terminal 2 and have approximate battery voltage. I also put a jumper wire from terminal 2 to terminal 4 as suggested here: No Spark Update and with the jumper wire in I still have no CEL. If I am reading that right it means that my relay is good...or perhaps doesn't mean anything at all.
I also have approximate battery voltage at the brass screw in the engine fuse box.
I've also changed the 15A EFI fuse located in the under hood fuse box, 7.5A Ignition fuse located in the fuse box at the drivers knee, 15A ECU-IG located in the fuse box at the drivers knee. None appeared to be bad but changed them anyway out of an abundance of caution.
I went back through the FSM procedure for removing the engine and verified that I didn't miss any steps when putting it back in. I also pulled the main harness in to the engine bay again and checked it for damage. I found one area that must have gotten squished during the install but none of the wires were broken. I wrapped them well with electrical tape and re-installed it.
Questions:
Would trying to start the vehicle with one of the white connectors near the ECU disconnected hurt anything?
I think a good next step would be to check for power directly at the ECU but I am not sure how to do that. Can anyone point me in the right direction?
Any other suggestions as to what should I try now?
Richard.
I had a low oil pressure situation that wiped out some bearings. Changing the rod bearings didn't fix the issue so I got a low mileage (about 147,000) from a 1997 FZJ80 to put in while I rebuild the original motor. Since the motor was on a stand I figured I would do the head gasket and re-seal the motor as preventative maintenance. While the head was off I had it completely rebuilt.
After pulling the original motor I swapped the accessories and manifolds on to the 1997 due to the minor changes throughout the years. I got everything installed back in the vehicle and now can't get it to start.
The issue:
I believe it is an electrical issue somewhere because I've got no spark. When the key is on the check engine light (CEL) doesn't illuminate at all (if I recall correctly it was working prior to the motor swap). Based on what I've read since the CEL doesn't illuminate that means I've got no power to the ECU (or is it ECM?) so that is the first place to start. I pulled the glove box back out and checked the connectors. I found that the four connectors plugged in to the ECU were fine but I had forgotten one of the white connectors. I plugged it in and thought for sure it would fire up but there was no change.
My fusible link appeared to be good but I changed it out anyway and have 12v at the other end of it. I've read many "No Start" threads and @Tools R Us will ask if there is power at the B+ terminal of the diagnostic connector on the firewall. I do have approximate battery voltage at that terminal. I think that means that the EFI circuit is good but am not certain.
I swapped the EFI relay with the power window one from the driver side kick panel and it didn't change anything. I can also feel the relay click when the key is turned. While it was out I tested for power at terminal 2 and have approximate battery voltage. I also put a jumper wire from terminal 2 to terminal 4 as suggested here: No Spark Update and with the jumper wire in I still have no CEL. If I am reading that right it means that my relay is good...or perhaps doesn't mean anything at all.
I also have approximate battery voltage at the brass screw in the engine fuse box.
I've also changed the 15A EFI fuse located in the under hood fuse box, 7.5A Ignition fuse located in the fuse box at the drivers knee, 15A ECU-IG located in the fuse box at the drivers knee. None appeared to be bad but changed them anyway out of an abundance of caution.
I went back through the FSM procedure for removing the engine and verified that I didn't miss any steps when putting it back in. I also pulled the main harness in to the engine bay again and checked it for damage. I found one area that must have gotten squished during the install but none of the wires were broken. I wrapped them well with electrical tape and re-installed it.
Questions:
Would trying to start the vehicle with one of the white connectors near the ECU disconnected hurt anything?
I think a good next step would be to check for power directly at the ECU but I am not sure how to do that. Can anyone point me in the right direction?
Any other suggestions as to what should I try now?
Richard.