Corsa 1.2LS - ECU light & engine cutting out

[SaddlerSteve]

Had a problem with the dreaded engine coolant temperature sensor a few months back but after a scout round on these forums i got a replacement sensor and the car has been driving perfectly ever since with no sign of the ECU light on the dash.

It's now coming up to MOT time so i had the car in the garage yesterday to have some bits sorted before the MOT at the end of the month.

Had 3 new tyres, front pads, rear shoes and drums, rear wheel bearings replaced, steering rack gaiters replaced.

After leaving the garage i noticed the ECU light was on and it stayed on permanently. Car drives perfectly until you start to slow down to below 30mph/20mph. Sometimes the battery light starts to flicker but then both the battery light and oil light come up and the engine cuts dead. It doesn't judder to a halt. Just cuts dead and carries on rolling forward.
It always restarts first time but occasionly the engine seems to rev itself without the accelerator being pressed.

Any ideas on what it may be? Seems a bit odd that it was fine before it went in to the garage and now its playing up?
Hoping to get round my mates tomorrow to put the diagnostic on and find out an error code.

[bluecorsab]

if its an 8v then its the stepper motor on the throttle body. I had a simular problem, mine wouldnt tick over at all. The replacement stepper motor has to be the same part number as the old 1 as there is 7 or 8 different ones. And they are very expensive. I was not willing to pay nearly 75 quid for a new 1 so got a whole new throttle body off a scrap car. Now runs perfectly hope this helps

[SaddlerSteve]

if its an 8v then its the stepper motor on the throttle body. I had a simular problem, mine wouldnt tick over at all. The replacement stepper motor has to be the same part number as the old 1 as there is 7 or 8 different ones. And they are very expensive. I was not willing to pay nearly 75 quid for a new 1 so got a whole new throttle body off a scrap car. Now runs perfectly hope this helps

Cheers for the advice.
Have got the car fixed now but it was something a lot simpler. My sisters boyfriend who works at the garage did all the work on my car and when I contacted him he said he'd come and have a look because he thought he knew what it may be. He came round, popped the bonnet and plugged a cable in, then we restarted the car and the ECU light had gone out. Been driving it round with no problem.

It turns out that when he was fitting the steering rack gaiters they had to move some things out of the way to get to them. There is a cable which plugs in directly above the coolant reservoir, just in front of the bonnet vents. He unplugged this to move the coolant reservoir so he could fit the gaiter. He'd forgotten to plug it back in which caused the ECU light engine problems.