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Re: difficult to cold start engine

   recently, I have problem to start engine cold in the mornings. It takes
   three or four times to get the engine fired. I put on four brand new
   spark plugs. the problem is still there without any significant 
   improvement. I checked spark plug wires which still look like new.
    I had the fuel filter replaced two years ago. the engine
   cylinder head gasket is leaking engine oil a little bit which I 
   don't think has anything to do with the problem. what could be the

My immediate suspicion would be the cold start injector/system. However,
just about any of n-dozen different sensors, connectors, grounds, and
the like could cause the engine computer to decide not to cooperate. As
an example, purely hypothetical, but I believe founded in Reality(tm),
if the "idle" [throttle-closed] microswitch is misadjusted, the computer
might decide that you are not "starting" the engine (disirregardless of
how slowly the engine is spinning...) and defeat the extra fuel enrich-
ment offered by the cold-start injector. Your temp sensor might be bad,
(I forget which way the curve is, I think hotter==lower resistance),
so if it "cracked"/"kroaked"/connector corroded/wire came loose/whatever,
the computer might think you're frozen at absolute zero and flood out
the engine; if the sensor shorted/cracked/kroaked/whatever, the computer
might think the engine is near meltdown and refuse to enrichen the mix-
ture at all. Depending on the year/system, there is a separate fuel-
pressure-regulator (which itself may have other systems regulating it)
which is responsible for cold-engine fuel-enrichment (above and beyond
the computer and the cold-start injector).

There are a myriad variations on the theme, and you'd be amazed (after
you recover from the depression) how one teeny tiny little thing wrong
can mess up so much else. [And, of course, you'd be equally amazed how
anything works at all (no obvious misbehavior symptoms) when a whole
*bank* of relays are inoperative due to a faulty/disconnected ground.]

Good luck.