Formula renault megane engine not firing

[Adi82]

Hello all,

I'm trying to help a college get a Formula Renault up and running for this season but they are having a few issues with the engine. They reccently purchased a Renault Megane engine along with the ECU and loom. They were told it was running fine on removal.

They have installed the engine but can not get it to fire up. There is no fuel being injected by the injectors and no spark from the spark plugs. They have a trace from the crank position sensor which is giving out 0.8V when gapped by 1mm to the trigger wheel. This increases to 2V when gapped to 0.8mm.

The trigger wheel, flywheel, ECU and loom are all stock megane items. They have had the injectors working when operating them manually. So it seems like there is no signal from the ECU to the spark plugs / injectors.

The few questions I have are:-

1. What is the correct output for the crank position sensor in volts?

2. Is there likely to be an immobiliser that requires decoding on the ECU before it is seperated from the car?

3. Could it be a fault ECU?

4. Any other ideas on what it might be or what they can try?

Thanks Adi

[DaneC]

Could be, in Mk1 Clios with immobiliser have a box in the car which forms a part of the immobiliser. A very early Clio ECU solves this problem, but with the Megane it might need decoding. Connecting the dials up and seeing if the immobiliser light flashes would be good, although properly not possible without interior loom.

[DaneC]

Use aftermarket management? The uni should have some funds for that!

[Wobba]

Have you taken the engine and box apart at any point?

It will likely be an ECU immobiliser issue, but yes, it could also be a blown ECU. Take the motheboard out of the casing and check for scorch marks/broken circuits or water.

You can get the immobiliser codes wiped, I think Stan mentioned it in a recent thread with similar issues.

[volymmannen]

megane has immobiliser must be that problem..

[pick]

megane immobiliser forms part of the fusebox with out the fusebox original key fob it wont start