Engine misfire when hot

[danbal]

Hi there,

My girlfriend has a 55 plated 206 1.4L which is currently having firing issues.

It all started when it developed a leak in the radiator and lost all it's fluid. She mentioned to me that the warning did come on and she stopped in time before it cooked the engine, although she did mention that the temp guage was right up in the red and the warning was telling her to STOP.

I got a brand new radiator as it was leaking profusely which seemed to be alright for a couple of weeks. The engine had a slight shudder which we shrugged off for some time until about a week ago she lost all the power on the motorway. I drove it when she got home and it sounded like it was running on three cylinders. I had the coil pack and spark plugs replaced. It now runs sweet when it's cold and warming up, but as soon as it gets up to temperature (seems to sit at just under 90 on the guage) it starts to shudder and misfire (not as bad as before) I have cleaned the Crank angle sensor as I have heard these give a lot of trouble and also checked the MAP sensor. The trottle body was also replaced over the winter.

I am unsure as to what to look at next or whether to replace the sensors?? also can the temperature sensors have an effect on the timing of the cylinders firing?
I might also check the pressure in the injector rail.

Cheers.

[gazza82]

Firstly not many of us have the 1.4 engine as this is the CC forum but most Pug engines work roughly the same way.

Temp sensor does affect engine as it sends info to ecu which in turn affects fuel mix ... so if it thinks it is running cold, it could run too rich. Or lean if it thinks its hot and isn't. Both will make the car run rough.

Also there is a known issue with certain coilpacks and NGK plugs so what have you got fitted now.

Get the car on a diagnostic as you could be throwing money on different parts only to find it wasn't them. EOBD diag should work but PlanetPeugeot 2000 or Diagbox is best.