1990 mighty max 2.4l 5spd troubleshooting

[90mightymax]

Hi im new here but i have visted the site a lot since i have owned my mighty max and i love it to death hear recently i just fixed it running rough with new o2 sensor and replaced fuel pump and of course my luck i had an accident spun the truck around and hit another truck now mine is running even worse than before its sputtering and will not accelerate on the too end when i try to wind out the gears really need help on figuring out what i need to repair because i dont want to have to scrap the ole girl ive grown very attached in my few months of owning it please help i have videos of it running and driving if that could help troubleshooting

[geezer101]

Hi and welcome to mightyram. First thing to do is an error code check from the ECU. This will tell you at least if it's a sensor or electronic failure. ECU's are known to go bad but are relatively easy to repair (common fault is bad capacitors) Second is the fuel filters. The hard hit may have stirred up a lot of debris or even rust from the tank and it may have either clogged the fuel pump or the filters. The fact that it still runs and starts indicates it's not a dead ICM in the distributor and the injectors are trying to run. Check the basic as well - ignition coil (they have a life span of approx 10 years before they break down), cleaning the injectors, spark plugs and related ignition components, EGR valve (a coked up EGR will affect running), IAC (sticking or leaking valves also affect idle/running). Then there are things that are overlooked like ground leads. A bad ground will cause all kinds of gremlins in the electrical system. Disconnect grounds from the block and chassis and give them a thorough clean at all surface contact points and refasten them firmly. Good luck :)

[90mightymax]

Thanks ill be sure to clean grounds thoroughly as well as injectors but as for reading the codes does autozone have the obd1 scanner test for free or do i need the adapter or what

[geezer101]

Thanks ill be sure to clean grounds thoroughly as well as injectors but as for reading the codes does autozone have the obd1 scanner test for free or do i need the adapter or what


It's a neanderthal check - no code reader. Putting the ECU into diagnostic mode will (should?) cause the CEL light to flash. You count the flash sequence and check it against the list of error codes. There's a how-to guide on the forum.

[Nevertk]

I pulled my ECU codes with a 20$ Analog multimeter. Worked like a charm. The needle will sweep back and forth each sweep is a count towards a fault code number