fuel issues in my 93 LS400... Keeps cutting off without warning
06-07-17 | 07:35 PM
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From: NC
fuel issues in my 93 LS400... Keeps cutting off without warning
Ok, background first... 1993 LS400 with 168,940 on the clock. Timing belt, whp, tensioners, seals, plugs, wires, caps, coils, battery, alternator, and ac have all been replaced in the last 2000 miles.
Ok, Monday I'm driving the car to run errands and it dies on me. No stutter or hesitation whatsoever, it was like someone flipped a switch. I put in neutral and tried to restart it with no luck. Coasted safely off of the road into a driveway and commenced to checking likely culprits. After checking all fuses interior and under hood with none blown I moved to the trunk to check the hinge harness. No rubs or broken wires there. I removed the side cover to expose the fuel pump ecu and noticed it was rather hot. ( Outdoor temp was 84°). I checked the FP relay next, it too was hot, the other relays in the box were not.
After about 10 minutes it fired up normally. I decided to head home in case it acted up again. I made it roughly 1/2 mile and it died again. Mind you when I left for home after the restart it ran perfectly with full power right up to the moment it cut off. No stumbling, hesitation, or stalling. Full power/ No power like a switch was thrown.
After an hour it still wouldn't crank so I had it towed home. Of course it fired right up when I got home. I went out this morning and removed the relay cover and folded down the trunk trim to expose the FP ecu. Verified that both were cool to the touch, then cranked the car. Outside temp was 85, so same conditions as when it died before. Within 5,minutes or so the relay and FP ecu were noticeably warmer. After 15 minutes they were both rather hot. At 17 minutes it cut off. Relay and FP ecu were both nearly too hot to touch.
What is causing this? Please help shed some light on my problem. I need my baby back on the road!
Sorry so long winded, I just wanted to be thorough in the hopes of finding an answer.
Thanks in advance for any help you can offer :-)
Ok, Monday I'm driving the car to run errands and it dies on me. No stutter or hesitation whatsoever, it was like someone flipped a switch. I put in neutral and tried to restart it with no luck. Coasted safely off of the road into a driveway and commenced to checking likely culprits. After checking all fuses interior and under hood with none blown I moved to the trunk to check the hinge harness. No rubs or broken wires there. I removed the side cover to expose the fuel pump ecu and noticed it was rather hot. ( Outdoor temp was 84°). I checked the FP relay next, it too was hot, the other relays in the box were not.
After about 10 minutes it fired up normally. I decided to head home in case it acted up again. I made it roughly 1/2 mile and it died again. Mind you when I left for home after the restart it ran perfectly with full power right up to the moment it cut off. No stumbling, hesitation, or stalling. Full power/ No power like a switch was thrown.
After an hour it still wouldn't crank so I had it towed home. Of course it fired right up when I got home. I went out this morning and removed the relay cover and folded down the trunk trim to expose the FP ecu. Verified that both were cool to the touch, then cranked the car. Outside temp was 85, so same conditions as when it died before. Within 5,minutes or so the relay and FP ecu were noticeably warmer. After 15 minutes they were both rather hot. At 17 minutes it cut off. Relay and FP ecu were both nearly too hot to touch.
What is causing this? Please help shed some light on my problem. I need my baby back on the road!
Sorry so long winded, I just wanted to be thorough in the hopes of finding an answer.
Thanks in advance for any help you can offer :-)
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