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Re: No low end power until warm

>Hairy green toads from Mars made RickBSE@aol.com say:
>> Is having a hesitation/lack of power from a standing start until the engine
>> is well warmed up "normal" in a 1989 100?
>> I ask because my dealer could not "isolate the problem."  It is NOT my
>> imagination.
>My '89 100Q sort of does this. If it is really cold (about 0F), it
>has no power at all until it starts to warm up a little. Pressing the
>throttle too much makes it seem like it's about to stall.


I would suggest to test the following things:
  - Cold start valve: remove and look if it sprays fuel when cranking)
  - "pressure change switch" (sorry, I try to translate the german word 
    "Drucksprungschalter"): When cold, this switch detects medium/hard throttle
    based on a jump in engine vacuum. Test: with *warm* engine "short cut" the
    temperature-based-vacuum-valve and connect the vacuum hose directly. Now the engine
    should (nearly) stall when accelerating caused by too much fuel. If this fails:
    + vacuum leak to or in the switch
    + bad temp timing switch
    + wiring of the temp switch or the cold start valve
  - pressure regulator; sorry here I don't know how to test it.

Good luck!