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ECM Compatibility


NAXJA Forum User
Fort Myers, FL
Have a 87 Cherokee, 4.0L EFI, Auto Trans. Computer got SOAKED this weekend. Took it out and poured water out of it.
Now no spark, no fuel pump.

Anyone know what computers are compaible with this setup?

Will a unit out of any 87 Auto 4.0L work? Maybe other years too?

Been searching around on ebay and such and have not found one that matches the exact part number.

Any help would be great!
87 thru 90 XJ or MJ 4.0L.
Take the cover off the ECM, and carefully take the computer pcb out from the case. Then put it in the dishwasher with calgonite soap and run a cycle. Don't let it do the dry cycle all the way. Take it out and let it air dry for a day, preferrably in the sun to dry it out completely. Maybe even hit it with compressed air to make sure all the water is out. Put it back together and see if it works. Most likely the water didn't do any damage. Washing pcb's in a dishwasher has been standard practice in the industry for years. I run all my hand soldered pcb's throught the wash before firing them up.

Before buying another computer, also pull the C101 connector above the brake booster apart and clean it out. Also do the same on the firewall bulkhead connector as well as the cps connector. If you had that much water, pull the distributor cap and make sure it is dry there as well. Good luck.
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