Cold start problems - 1993 90 V6

[David VS]

Thanks Todd,

You confirmed what I was originally thinking... the (ECM) engine coolant
sensor could be bad.  One more thing, the check engine light does flicker
now and then, plus will stay on after driving the car for a longer period of
time.  This may or may not be related to the cold start problem... I may
have to break down and buy a VAG-Com one of these days.

I think I'll try a new sensor and double check the timing.  Then go from
there.

Thanks again,

Dave




> Hmmm, I would think it would somehow be related to what the computer
> thinks the engine temp is. Therefore, I would check the ECM (ECU,
> whatever the heck you want to call it) temp sensor. Let's see, there are
> two temp sensors, one for the gage and one for the computer. Gage sensor
> is on the passenger side, the ECM sensor is on the driver's side of the
> steel coolant pipe running along the back side of the engine.
>
> If the "check engine" light isn't on, the stealership most likely
> charged you for nothing. If I remember correctly, OBD1 in the Audi 90
> series does not store codes after the engine is turned off. So pretty
> much they were "blowing smoke up your ass".
>
> I suppose if you didn't get everything lined up exactly between the cams
> and the crank, you could have some hard starting issues. That would also
>   explain the "back fire" condition.
>
> David VS wrote:
> > Seems that the colder it gets outside the harder it is to get my
father's 90s started.  Any ideas?  With temps in the 30's (F) the motor will
sputter and spit when turned over - sometimes even back-firing through the
intake.  Only after serious flogging of the starter will it run and even
then it's not running on all 6.  When the motor does finally warm up, it
seems to run fine.
> >
> > My father took it to the local Audi wrench and they plugged the car into
their computer and cleared any codes.  They concluded that the motor was out
of time.  Which I suppose is possible since I did change the water pump and
timing belt last spring when rebuilding the motor (due to a seized water
pump... and bent valves).  But I did use "the" tool for holding the cams and
crank.
> >
> > Any ideas are greatly appreciated!
>
> --
> Todd Young
> 7079 Dawn Ave. E.
> Inver Grove Heights, MN 55076
>