How possible is it that water could have caused a spark to jump and short out my ECU?

89 S10 4.3 220k. My truck ran fine before I decided to powerwash the engine. After I washed it It wouldn't start. When I did get it started, it was misfiring badly and would backfire out of the intake. The plugs and wires I changed at the last oil change. I tried replacing the distributor cap, rotor and the pickup coil. I also had the Ignition module tested and it tested good. I tested the coil with an ohmmeter and it was good as well. Could a spark have jumped into the wiring harness and zapped my computer?How possible is it that water could have caused a spark to jump and short out my ECU?
No.. you forced water into the plug wires with the pressure washer and it's cross firing between two cylinders.... plug wires are designed to keep water out at atmospheric pressure, not at 3200psiHow possible is it that water could have caused a spark to jump and short out my ECU?
No.How possible is it that water could have caused a spark to jump and short out my ECU?
The ecu is not at fault. Don't power wash your engine. If you are lucky it will dry out after it runs for a while and warms up.How possible is it that water could have caused a spark to jump and short out my ECU?
Not likely.......It's probably water somewhere in one of the connectors, you might want to carefully disconnect them one by one, and replace the dielectric grease

in them, you can also try clean, compressed air. I personally have

never heard this happening but I guess there's always a first if it is

the ECU....But being it's such an expensive item to replace, I would

try all other options first.



Good Luck to you..How possible is it that water could have caused a spark to jump and short out my ECU?
the difference between the coil secondary and any other system in that car is just too much. even if the spark could wander to the computer it would lack the power to do any damage. allot of us agree that your problem is simply just wet ignition system. dry it out and retry.