This afternoon I changed the valve cover on my 08 s, When I went to start it it fired up then I heard and electrical pop and it died, it was coding CF and U codes indicating that the ECU was offline.

I realized that when I put the ground wire back on the front of the block i over tightened it and the ground was broken, it appears it sparked off causing the popping noise I heard.

All of the fuses for the ECU Look fine and I cycled the relays but it still won’t come back online. Is it likely that the ecu is just dead (the car cranks just won’t get fuel or spark)

Or is there somewhere else I should look?

 

Unplug the battery and leave it for an hour or 2. That usually resets my ecu when this happens. Are you sure your fuses are good? Check the first 3 in the engine compartment.

 

I did this a few times this week with no luck. The ground is repaired and good and all the fuses for the ecu are ok.

Here are the raw codes:

If I clear the codes they immediately come back. My keys seem to still work and the car will crank. Should I order a new ECU and or what’s the next troubleshooting step?

 

Hi, I had a car that another shop did an oil pan on and then subsequently pulled the transmission because it kept leaking but long story short.. afterwards the car wouldn't start because of two things. They pinched the crankshaft sensor wire and then left the ground on the transmission loose frying the ecu when trying to start it. So if nothing is pinched then I'd say it sounds like you have a Cajun style ecu