ECU, new parts, and still having problems....

[Sazzzer]

Firstly, I have to let you know that what I know about cars you could fit on the head of a pin. I am asking for help here on behalf of my brother, and what I write below is from notes he has given me, so I apologise profusely in advance for any stupidity on my behalf.

OK. My brother has a V reg Corsa B. 1.2cc 16v automatic.

He took it to our local garage for it's MOT and asked the garage guy (GG)to check it over, as he had had some problems with the car not starting and being a bit sluggish. When he went to pick it up, it had passed the MOT, but GG said it had shown up some problems on the ECU and it would need a new crank sensor and a new air flow sensor. My brother bought these parts and fitted them himself. The car seemed to run better, but according to the manual, now needed to have the ECU reset because he'd fitted new parts. He took it to GG. GG reset it for a Corsa C, my brother corrected him that it was a Corsa B, so GG tried again for a Corsa B. GG then told my brother it still wasn't running right, it runs at 3000rpm on idle, so it now needs a whole new throttle housing replaced. GG has said he will do this as a favour and only charge £10, but has now had the car for two weeks. My brother went to the garage yesterday to find that the car still isn't fixed, but GG has put on a second new air flow sensor. GG also said that he put the red box (?) on the ECU and it still reported an air flow meter fault.

From the little bits of information that have I have tried to read on the internet, I am thinking GG knackered the ECU while resetting it, and is now trying desperately to fix it up somehow, but like I said I know less than nothing.

Any help or advice would be very gratefully received, and I thank you for reading. I hope it made some sort of sense.

Thanks, Sara

[Sam58]

First of all, if the car passed its MOT, then ALL the sensors had to have been ok in order for the car to pass its emission tests.
The air flow sensor not working properly would have caused the car to run roughly, poor aceleration, poor starting etc. It would also have caused a failed MOT. Crankshaft sensor could well have been the cause of poor starting and running, again this would have caused an MOT failure. Either, or both of these sensors would have put the car into get you home mode, again a failure of mot.
I do not think that using the corsa c codes would damage the ecu, or the new air flow sensor. The question must be is this guy capable to work on your car or not. Sounds very iffy to me.

[Sazzzer]

Thanks very much for your reply Sam, I'll pass it on to my brother. But you've got me worried because I usually get my car MOTed there too. I may well be looking for a new garage, and I think my brother should probably get his car and take it somewhere else too.

[Davva]

Yr 2000 Corsa B, 1.2, 16v, would intermittently cut out (or so we thought) but would restart when the engine cooled.
I removed the crankshaft sensor (next to OSF inner drive shaft) & measured it as 500,000ohms, instead of the correct reading of 1000ohms .

I then dangled the sensor over a boiling kettle to simulate engine heat & within 30seconds, it went open circuit!
So, it proved not to be that intermittent in that it would fail seconds before the fan would cut in, so at max' engine temperature.

Did the same test wth a new sensor (£20 at the local factors) & it was 'rock solid' at 1000ohms & all is now well