cold stalling each year,what can be wrong?

[petaling]

last yr cold stalling usually at incline or turning off ramp ,usually at minus 10 to 20 degree celsius
rest in underground heated car park.starts again
changed voltage regualtor,same thing
changed back from plat to copper though resistance plugs ,same thing
finally last yr mechanic over the phone diagnosis,change battery,went thru last yr without further stalling.This yr got new battery again one month ago as prophylaxis just in case.so battery Interstate 91 HD only 1 month old.

This yr 1st cold snap,yesterday and today minus 20 celsius,ie minus 4 fahrenheit, or 4 below F.stalled again,jumpstarted sputtered and started.
Added gas line antifreeze to already almost full tank.

checked battery,12.35 with ignition off and alarm on only.Idling,13.8 -9 V,1500 rev 14.0 or 14.1 V. With batt disconnected tonite after driving home and charging battery by alternator only ie by driving home,12.77 V (disconnected from car)

I am thinking of changing the plugs to mercedes non reistance plugs,other than that,are there anything that one may suspects,Are there any grounding points for the alternator that is easy to reach in cold weather.The groudning point for the battery negative terminal seem s okay.


bad contacts when cold,bad contacts at ecu???????Dist rotor and Bosch wires only few yrs old.

Thanks for any advice

[petaling]

p.s.when i lived in Manitoba cold country,used to attach cardboard to grille of car to keep car warmer,
should i do the same with the MB,but may be unsightly for such a "status "car!!!!!!!!!
anyone in Minnesota,North Dakota or Manitoba,Sasketchewan or Edmonton doing same?

[Jackd]

I never heard of a battery or alternator causing an engine to stall Look somewhere else.
Have you replaced your fuel filter?.
How's your cold start injector?
Have you checked fuel pressure?
How's your idle control valve?
Any vaccum leak?
Get back to real MB plugs.
You saidist rotor and Bosch wires only few yrs old
......don't assume they are perfect. Check/test them.

[petaling]

idle control valve was checked by mechanic,okay
fuel filter few yrs old.

The funny thing is it always started by jumpstarting from another car.
What can cause this??????


It seems to me jump starting only good to take place of non functioning battery,charging system.If the fuel pressure/fuel filter is no good,how can jump starting start the car????

[petaling]

I am no mechanic but
2 facts may hold clues
:
(1) always restarts with jump starting (despite battery and alternator both seems okay later).
(2) only happens at minus 10 to 20 celsius(4 degree below F)NOT when weather is warmer.

Thank you for your responses

[schumi]

I would have the amp output of the alternator measured and the battery voltage measured while car is running in very cold conditions. you said they seem ok but you have to take some readings I think.