Warm Engine - No Start

I own a W reg 2000 Mk II Punto, at 174,000 miles I blew the head gasket (second one). As the engine had so many miles on it, I decided to replace the motor instead of having the head gasket replaced. I sourced one from a Fiat Specialist (reputable) that I have dealt with many times in the past. He managed to get me a motor from a 2003/4 model with less than 10,000 miles on the clock. Over weekend we managed to remove the old motor and replace it with the new motor. For the most part the swap was pretty straightforward with the exception of a couple of the sensor locations. Once the motor was installed it fired right up and ran like new. However we are experiencing one problem. When the car gets up to normal operating temperature and you switch the ignition off, the car will not start back up until the engine has cooled down to approximately the quarter mark on the temperature gauge.

When the engine is at “Normal Operating Temperature” and you turn the engine over it is as if it is not getting or the ECU is not allowing fuel to flow. I have tried replacing the “Intake Air Temperature/Pressure Sensor” but this has made no difference. The Haynes MkII Punto manual offers no real guidance and refers you to the Fiat dealer.

Any help from members of this forum would be greatly appreciated.

Thanx
Greg

OK, presumably you changed the manifolds over, wiring and sensors so you only effectively changed the engine block. If not then change the sensors over as the calibration could be different. Alternatively check the airgap on the phonic wheel, ideal is 0.75mm, a bigger airgap can cause starting problems.

OK, presumably you changed the manifolds over, wiring and sensors so you only effectively changed the engine block. If not then change the sensors over as the calibration could be different.

Yes, have done this and/or a combination of these suggestions.



Alternatively check the airgap on the phonic wheel, ideal is 0.75mm, a bigger airgap can cause starting problems

Have not tried this as I do not know how, so how do I do this?

Thanx again
Greg

Okay NumanR, you have my attention: phonic wheel

Greg