I have an 88’ Toyota truck 160k miles. Been serviced regularly. Previous owner turned it on its side but truck ran fine for the first year I had it. It started running rough in idle and cutting back and wanting to choke out while driving at cruising speed. When it does that while driving the check engine flashes on/off each time it chokes. I recently changed wires/plugs but didn’t seem to help. I’ve been running either 100% gas or 93 to try to clean the system. Any advise would be greatly appreciated. Thanks
88’ truck running rough
- Thread starter lilredtruck
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check engine doesn’t stay on. Only flashed on/off when the truck tries to choke out.
The light doesn't need to be on to check stored codes.
If you actually have no codes and the CEL is coming off and on, i would say your computer is likely turning off and on for some reason....
If you actually have no codes and the CEL is coming off and on, i would say your computer is likely turning off and on for some reason....
My first guess is fuel pump.
I also agree, pull the codes. Codes can be stored in the ECU without the check engine light on.
I also agree, pull the codes. Codes can be stored in the ECU without the check engine light on.
Zjohnsonua
SILVER Star
As they said: pull the codes, but be prepared for them to be mildly useful. That ECU is ancient.
My '86 used to do this. The fuel pump connector was under the passenger door sill trim - you know, right were water will collect when windows are left down. The connector left a lot to be desired even when new (unsealed and poorly restrained to relative movement) so the pins will fret, corrosion sets in, and leave you with an intermittent open circuit. I cleaned the pins, reconnected, and installed a little ziptie to hold the two sides together. No more pump dramas.
My '86 used to do this. The fuel pump connector was under the passenger door sill trim - you know, right were water will collect when windows are left down. The connector left a lot to be desired even when new (unsealed and poorly restrained to relative movement) so the pins will fret, corrosion sets in, and leave you with an intermittent open circuit. I cleaned the pins, reconnected, and installed a little ziptie to hold the two sides together. No more pump dramas.
As everyone else said: pull the codes but be ready to pull your hair out. I've found the traditional "fuel, air & spark" is mountains more of advice than anything the ECU could offer.
It does sound like your fuel delivery is subpar.
It does sound like your fuel delivery is subpar.
Once in a blue moon(6 times max in 8 years) my check engine light lit up for around 30 seconds and shut off with no code stored. It was running mint with the check eng light on. Could be an anomaly. If youre experiencing loss of power at random I'd look at fuel.
The truck I am working on sounded rough when it was fired up and moved off the trailer when it was brought it. I was not excited about doing body work and having to get the engine running well. I had read somewhere on here about the pins in the ECM getting fatigued with the weight and vibration of the connector cable over time. So, I pulled the cover off the ECM since it was already out and looked at it through my shop microscope (not necessary but handy) and found issues with ~80% of the pins. Cleaned up and soldered and the truck purrs like a kitten now.
