[Vwdiesel] TDI Starting Poor

[Val Christian]

I haven't had time to check, but will.  (Hard rain and tommorrow wind
and rain).  The fuel sight line shows slightly more than the average
air bubbles.  

Normally, I'd associate problems with cold starts being tied to 
fuel intake restriction.  But recently, I've had a tank or two
of commercial fuel, so that could contribute to problems.  

Years ago, I went to an on-site fuel tank, and the additional
filtering is GREAT.  It makes it worth the hassle.  However, 
I hear that the EPA/DEC will soon make the burden of small
farm diesel tanks much greater.

Back to the starting...I should make it clear...the car starts absolutely
fine at -25C, -10C, 0C, and 20C.  Between about 5C and 15C it takes 
about 20 seconds (sometimes more) to get going.  Then, white smoke
from unburnt fuel when it first fires up.  After 5 seconds of running
no smoke.  The behavior is predictable by checking the coolant temp
prior to starting, either with VAG-COM, or a radiometer.

Val


> 
> > Loren mentioned intake blockage.  I'll check that; I haven't yet.
> > Why would the intake change starting performance in a narrow temperature
> > range?  Or is it simething you've seen before?
> > 
> 
>   I've just seen cases where restricted intake (dirty air filter usually) can 
> 
> cause hard cold starts or hard warm starts.  In this case it can have to 
> do with volatile hydrocarbons soaked into the carbon and releasing at 
> certain temps.  Since it's such a problem area anyway, it hit me as an 
> early thing to check just in case.  Plus I'd just been at my friend's shop 
> where he was cleaning one out that would hardly start at all under most 
> conditions and barely run.  
>      Loren