Hi Everyone.
This issue exhausted me and my pocket, and nearly driving me to lose my mind. Your help will be much appreciated.
I have a 93 LC80 1fz-fe engine Auto tran. Problem has 2 parts.
Part one: NO CEL, cranking no firing
Initial issue it cranks good but engine doesn't fire up. When that happens:
1- No CEL on dash
2- +12 running through all 3 wires of the fusible link, black fuse box Phillips screw
3- EFI rely ticked, EFI 15amp and 7.5 charge fuse checked with V-meter
4- +12 on Pin 2,4 of the EFI rely
5- +12 on pin 8 B+ in the diagnostic port
6- +12 on the wire powering the ignition coil.
7- Ground connectors to chaise are all tightened.
I noticed that one of the 3 links of the fusible links (the pink one) lost its clip and was skinned and connected directly from the previous owner. this tested +6 VDC as it was very very dirty. I cleaned it up and reconnected it good, it tested +12. After doing that, CEL came back on and it fired up and drove fine but while driving, the engine shut off completely, CEL wasn't illuminating, still +12 on the skinned pink wire of the fusible link, seconds later CEL came back on and the engine fired back again.
Part 2: CEL on, Engine fires then it shuts off, CEL goes off then on again.
I replaced the fusible Link, EFI relay, 15amp EFI fuse, 7.5amp Charge fuse. The CEL came back after I replaced the F-link, engine fired from the first crank, and drove it for few days (with AC) for over 100km each trip, she ran beautiful. Then all of a sudden while parked engine running in idle with the AC on, the engine shut off, and the CEL wasn't illuminate. Few seconds later, CEL came back on, it stared and managed to get home with AC turned off. I had the time today to inspect it thoroughly with a V-meter.
WHILE CEL ON, Starting from the
- battery +12,
- battery links +12,
- fusible links all 3 gave +12,
- Phillips screw in the black fuse box +12,
- EFI rely ticks and pin 2,4 gave +12,
- EFI and charge fuse gave + 12,
- B+ gave +12.
CEL was on so I had it run for a while without the AC, then had the AC on, after half an hour (while the AC on) the engine shut off, CEL went off then came back again. I started it again, then as soon as I turned the AC on it went off immediately and the CEL was not illuminating. While CEL was off, I checked everything listed above again. One thing I've noticed, the black box Phillips screw gave +12 BUT the EFI/ CHARGE fuses read something like +1 VDC indicating no current (where when the CEL was on, they gave +12). While the EFI/ CHARGE had no current, I skinned a little bit of the MAIN fusible link wire between the gray clip and the black box, it read +12, AM1 and AM2 links still reading +12. After couple of minutes CEL came back and the EFI/CHARGE fuses read +12, engine started.
The reason I skinned/checked the MAIN wire in the fusible link because I read somewhere that (one way to check if the MAIN link is ok from the driver seat is to turn the AC on) and since my engine went of when I had the AC on the second time.
Does this mean bad wiring feeding into the black box somewhere in the LOOM between the MAIN fusible link and the black box? or bad wiring between black box and the fuses within it? (I removed the back box, looked at the underneath wiring, it all looked intact). Maybe bad harness loom?. Would MAF be a responsible of turning CEL on/ off?. Anything behind the left kick panel?. Fuses in the driver knee side are all checked OK with the V-meter.
New parts changed so far trying to eliminate every possible reason, and since the car didnt come with service history when I bought it:
Fuel: fuel pump, fuel filter, fuel regulator, injectors are all checked.
Electric parts: Ignition coil, distributor cables to IGN coil/ spark plugs, distributor rotor, spark plugs, TPS, fusible link, EFI relay, EFI fuse, Charge fuse, ECU IGN fuse, Fuel pump rely.
This issue exhausted me and my pocket, and nearly driving me to lose my mind. Your help will be much appreciated.
I have a 93 LC80 1fz-fe engine Auto tran. Problem has 2 parts.
Part one: NO CEL, cranking no firing
Initial issue it cranks good but engine doesn't fire up. When that happens:
1- No CEL on dash
2- +12 running through all 3 wires of the fusible link, black fuse box Phillips screw
3- EFI rely ticked, EFI 15amp and 7.5 charge fuse checked with V-meter
4- +12 on Pin 2,4 of the EFI rely
5- +12 on pin 8 B+ in the diagnostic port
6- +12 on the wire powering the ignition coil.
7- Ground connectors to chaise are all tightened.
I noticed that one of the 3 links of the fusible links (the pink one) lost its clip and was skinned and connected directly from the previous owner. this tested +6 VDC as it was very very dirty. I cleaned it up and reconnected it good, it tested +12. After doing that, CEL came back on and it fired up and drove fine but while driving, the engine shut off completely, CEL wasn't illuminating, still +12 on the skinned pink wire of the fusible link, seconds later CEL came back on and the engine fired back again.
Part 2: CEL on, Engine fires then it shuts off, CEL goes off then on again.
I replaced the fusible Link, EFI relay, 15amp EFI fuse, 7.5amp Charge fuse. The CEL came back after I replaced the F-link, engine fired from the first crank, and drove it for few days (with AC) for over 100km each trip, she ran beautiful. Then all of a sudden while parked engine running in idle with the AC on, the engine shut off, and the CEL wasn't illuminate. Few seconds later, CEL came back on, it stared and managed to get home with AC turned off. I had the time today to inspect it thoroughly with a V-meter.
WHILE CEL ON, Starting from the
- battery +12,
- battery links +12,
- fusible links all 3 gave +12,
- Phillips screw in the black fuse box +12,
- EFI rely ticks and pin 2,4 gave +12,
- EFI and charge fuse gave + 12,
- B+ gave +12.
CEL was on so I had it run for a while without the AC, then had the AC on, after half an hour (while the AC on) the engine shut off, CEL went off then came back again. I started it again, then as soon as I turned the AC on it went off immediately and the CEL was not illuminating. While CEL was off, I checked everything listed above again. One thing I've noticed, the black box Phillips screw gave +12 BUT the EFI/ CHARGE fuses read something like +1 VDC indicating no current (where when the CEL was on, they gave +12). While the EFI/ CHARGE had no current, I skinned a little bit of the MAIN fusible link wire between the gray clip and the black box, it read +12, AM1 and AM2 links still reading +12. After couple of minutes CEL came back and the EFI/CHARGE fuses read +12, engine started.
The reason I skinned/checked the MAIN wire in the fusible link because I read somewhere that (one way to check if the MAIN link is ok from the driver seat is to turn the AC on) and since my engine went of when I had the AC on the second time.
Does this mean bad wiring feeding into the black box somewhere in the LOOM between the MAIN fusible link and the black box? or bad wiring between black box and the fuses within it? (I removed the back box, looked at the underneath wiring, it all looked intact). Maybe bad harness loom?. Would MAF be a responsible of turning CEL on/ off?. Anything behind the left kick panel?. Fuses in the driver knee side are all checked OK with the V-meter.
New parts changed so far trying to eliminate every possible reason, and since the car didnt come with service history when I bought it:
Fuel: fuel pump, fuel filter, fuel regulator, injectors are all checked.
Electric parts: Ignition coil, distributor cables to IGN coil/ spark plugs, distributor rotor, spark plugs, TPS, fusible link, EFI relay, EFI fuse, Charge fuse, ECU IGN fuse, Fuel pump rely.
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