on r/r 1997 4.6 p38 plus got a missfire. no ex/blockage . glows red hot after only 3 mins:confused:

It is usually a sign of the fuel mixture being too lean. In some cases though it can be running too rich but 9 outta 10 times it's cos it's too lean.
 
That's got to be effing lean!
And its a cat-motor, so the lmabda shouldn't let it run that lean...
Something is very wrong, and I suspect, very expensive, cos although cats are designed to run hot, if they get THAT hot, then the catalyser core will be breaking down.
I wonder.....
Could be a 'reverse' effect symptom; if the cats have started to break down, and the Lambda is leaning the mix off becouse the cats aren't doiing thier job, and the Co readings its getting are too high, suggesting the fueling too ritch' so its leaning the injectors off to compensate, making it run hotter and burn the cats more.......
Suggest its a job for a diagnostics centre; get some sensor readings.
 
That hot could melt any plastic air pipes or insulation on elec wires or !! plastic fuel lines!! Nuff said !
 
That's got to be effing lean!
And its a cat-motor, so the lmabda shouldn't let it run that lean...
Something is very wrong, and I suspect, very expensive, cos although cats are designed to run hot, if they get THAT hot, then the catalyser core will be breaking down.
I wonder.....
Could be a 'reverse' effect symptom; if the cats have started to break down, and the Lambda is leaning the mix off becouse the cats aren't doiing thier job, and the Co readings its getting are too high, suggesting the fueling too ritch' so its leaning the injectors off to compensate, making it run hotter and burn the cats more.......
Suggest its a job for a diagnostics centre; get some sensor readings.
Or he could just sort out the misfire and stop the unburnt fuel from burning in the downpipes/cats.
"Lambda is leaning the mix off because the cats aren't doing their job" I dont think so,the sensors are before the cats and will be shortening the pulse width of the injectors to try for a 5v signal,making the cyls that are firing as lean as can be.
 
That's got to be effing lean!
And its a cat-motor, so the lmabda shouldn't let it run that lean...
Something is very wrong, and I suspect, very expensive, cos although cats are designed to run hot, if they get THAT hot, then the catalyser core will be breaking down.
I wonder.....
Could be a 'reverse' effect symptom; if the cats have started to break down, and the Lambda is leaning the mix off becouse the cats aren't doiing thier job, and the Co readings its getting are too high, suggesting the fueling too ritch' so its leaning the injectors off to compensate, making it run hotter and burn the cats more.......
Suggest its a job for a diagnostics centre; get some sensor readings.


Same thing happened to a mate of mines Peugeot 406.
 

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