Second fried VR6 ECU - help!

[hirstd68 10]

It appears that I have an intermittent wiring fault in my VR6 that has (so far) fried two Bosch ECUs. First time it happened, the engine juddered a lot for about 10 seconds, like an intermittent electrical fault, then died. Investigations revealed what was virtually a fire inside the ECU box. "OK, may a duff unit" methinks. Replaced it and everything ran fine for 4 hours, then the rough running started again but this time the car kept running. Thinking that it might have been a timing sensor this time, I replaced the distributor and got new ignition leads. Ran fine again until 5 min later when it started coughing again, then wouldn't start.

Opened up the 'new' ECU to find the beginnings of the same problem: an internal board track (on the very left with the connector toward you) was overheating and causing the board to char and expand, breaking another track in the process. Being an internal track, it's difficult to find which pin or circuit it's part of, short of dismembering a board with a mill drill and sandpaper.

I've had a quick look though the fusebox and wiring and couldn't see anything amiss. The car is now with an auto-sparky but I can tell that he's losing the will to live when trying to find an intermittent fault in the 48-odd connections to the ECU.

So.

Anyone here had any similar fault? Any clues? Any moral support?:bonk::bonk:

 

Cheers

David

[VEEDUBBED 0]

Er, chin up and happy easter!!

Which reminds me, i do have a spare ecu..

[odub 0]

I fried an ecu when my wiring to the lambda sensor was damaged and shorting out. May not be your cause but could be worth a look under the car

[swiftkid 1]

I'd go round all your wiring loom looking for splits or places where wires could be broken. Also worth cleaning up all your earth's, I wouldn't plug another ecu in until your happy it definitely won't happen again!