Misfire At Startup

[Guest gritrash]

My 130tdi has 5k on the clock and has had a misfire at startup since new. The dealer has had it, plugged the computer in and.... surprise surpise found no fault codes.

It only happens when starting from stone-cold (ie first thing in the morning), engine fires intantly then runs for about 1 seconf before a short misfire (perhaps two or three cylinders??) which produces a large cloud of blue smoke resulting from the poor combustion i guess. The smoke is way above the level you would expect when ordinarily starting a diesle from cold.

Any clues any body? My initial thoughts were malfunctioning glow-plug system, but it does start OK and continue running (even in sub-zero temperatures)

I had the 130tdi engine in a golf immediately prior to the gal and it was sweet as a nut right from the moment the key was turned.

PS - is there potential that this misfire could be damaging the cat?

[johnb80]

Air leaking into the fuel line is the first thing that springs to mind. I had a similar problem on a new Transit, changing the fuel filter cured the problem.

 

Regards - JB

[Guest gritrash]

thanks JB - that could well fit with the symptoms

[Guest SA Intruder]

Won't show up as fault on diag.

 

First port of call is filter/pipes.

 

Insist these are replaced/resealed. I had faulty filter.

[Guest gritrash]

is there a reason why this only occurs when cold? Is there likely to be higher residual pressure in the system at subsequent start-ups during any given day? Or just not enough time for air to have entered the system?

[Guest SA Intruder]

Air has entered the fuel supply line and formed bubbles.

[johnb80]

When it's cold it's been stood longer and hence more air into the pipes which gives a longer misfire.

 

Regards - JB