BermudezLS

Driving home from college when CEL started flashing, loss of power, coasted to a parking lot and got towed home. Was able to start vehicle next morning, running on half its cylinders unplugged 4 coil packs on driver side bank 1 (1,3,5,7) was able to verify cylinder 8 coil pack would fire intermittently. Verified timing, crank, and cam signals, power and ground to all the coils. But no control or confirmation igniter signals coming out of the ECU. Very rarely I got a control signal to cylinder 8 coil pack. Thinking it was typical ECU failure I procured a used ECU from the junkyard same part no. 89661-50501 and swapped the parts. Visually I did not see anything obviously wrong with both computers yet it still doesn't want to start. I attempted to start vehicle with carb spray and it didn't even attempt to fire. So I believe my issue is spark related and now doesn't want to run at all.

Any suggestions would be a big help thank you.

CLLEXUSS

What parts exactly did you swap along with that ecu replacement? Just the ecu or anything along with that?

BermudezLS

I've only replaced the ECU, I moved coil packs around in the beginning. I don't fully know the theory of operation for the car to send spark if I have correct timing, fuel, good fuses, and no mechanical concerns.

CLLEXUSS

Earlier models you can get away with plug and play replacement of ecu's, later models not so much. There is programming involved.

BermudezLS

I saw the key code DTC and swapped old ECU back in. Attempted to start with carb spary and still didnt spark. Im backprobing crank and cam signals again from sensor and ECU to double verify.

BermudezLS

Crank signal is immediate through both sensor and ECU, Camshaft is slow signal on ECU and almost nonexistent from sensor. There is a small nick dent on cam sensor face, ordered a new cam sensor for tomorrow and will update if that solves problem.

Yamae

Why don't you read diag codes first before jumping to replace the ECU without re-writing the immobilizer chip?

BermudezLS

The only codes I had were multiple misfires on 1,2,8. with no ignition control signals coming out of the ECU is guessed it to be ECU. I read online about it not needing reprogramming but obviously was wrong. Still have no ignition on driver side bank 1. I did the dreaded compression test on all cylinders with number 1 reading zero PSI. So this is turned to a big can of worms. Will continue to update what I find.

timmy0tool

iTrader: (7)

how many miles? have you checked fuel? you checked spark but fuel is next.

zero PSI is not good but typically that's user error where the chamber likely isn't sealed properly from wrong engine rotation or bad plug seal. you should get low numbers if something is wrong, not just a straight 0!