Hello all, I need help diagnosing my 94 1fz. Over the past couple days while driving around 2k rpm, the engine would “cut out” and I would lose power. The engine would not stall but the vehicle would jolt forward then no power was being delivered to the wheels. While this is happening, the engine would not be very responsive to the accelerator and was unable increase in RPM. I would then pull over to the shoulder, put the car in park, wait a second then resume driving like nothing happened. It has done this a few more times and then snaps out of it. I have read some other forums about this possibly being a fuel delivery issue like a clogged/collapsing fuel filter or even a failing fuel pump. It’s odd though because my engine does not struggle to reach 5k rpm occasionally. It is very random when the engine decides to “cut out”. I bought my truck about 2 months ago and have done most of the preventative maintenance on it. The previous owner owned it for 4 years and only put 604 miles on it so it has been sitting for a very long time. Thanks in advance!
94’ intermittent loss of power/ cut out.
- Thread starter tcorley37
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Fj80oregon
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What have you done for preventative maintenance?
- Thread starter
- #3
Cleaned IAC/throttle body, new cap, rotor, spark plugs & wires, new alternator, changed all fluids, new battery, pair valve delete with new o2 sensors in its place, new vacuum lines, refresh coolant, air filter, a couple other things but I can’t think of them now.
What have you done regarding maintenance most recently? It's usually the last thing you did.
Also, have you checked your transmission fluid? Almost sounds like the transmission is slipping, from your description. Need more info on what happens just before the loss of power,
Also, have you checked your transmission fluid? Almost sounds like the transmission is slipping, from your description. Need more info on what happens just before the loss of power,
Have you checked the wiring harness near the EGR? The harness is known to melt and the wires can short out.
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- #6
I listed previous maintenance in the comment above. Most recent work was the pair valve delete and installing the new O2 sensors in their spot. But I had the loss of power before this precious work. I can’t remember exactly what I did before it started cutting out. Transmission fluid is full, It didn’t feel like it lost power while shifting, just randomly cut out while driving a steady speed.
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- #8
I read some other forums about similar issues and somebody mentioned having a loose battery terminal or loose EFI fuse. I checked my battery terminal and one was fairly loose so I tightened it. I also made sure my EFI fuse was securely in place. I have driven about 40 miles since doing so and the engine has not cut out. I hope that this was the fix. I will revisit this if it happens again.
- Thread starter
- #9
No melted wires
Good. Hopefully you can stay ahead of that and wrap it so it does not happen. My mechanic was able to source a harness for me and wrapped the area that does melt, so I should be good for another 30 years.
- Thread starter
- #11
Did it again over the last couple drives, it once struggled to idle while in park with dropping rpm’s. I believe I have this problem down to a fuel issue. The most likely culprit from research is either leaking/ clogged fuel injectors, or a clogged fuel filter. This would make sense as the previous owner only drove the car 600 miles over 4 years, so the truck has been sitting for a while. I will be posting another thread to ask how to test fuel pressure to see if I have a leaky injector or weak fuel pump.