Typically screeches on startup come from one of your accessory drive
belts.  I would head back there and see if any are loose (loose belts
typically cause screeching).  If they are, tighten them.

You may want to pay attention to when the screech occurs, as most of the
time a belt screech can be made to appear when the accessory it drives
is put under load, i.e. if the screech re-appears when you turn the
steering wheel, suspect the power steering drive belt.  Likewise if the
screech appears when you turn on the A/C, check that one out.

I suppose your problem could be something else, but there aren't too
many things that get described as a screech that aren't belt problems.
It also makes sense as most of the belt screeches I've heard will go
away if you rev the engine.

Good luck,
Sean

>
> With the onset of colder weather here in WY, my van has taken on a new
> ailment.  When I first start the engine and the engine is cold, it will
> idle at about 400 RPMs and a high pitch screech will sound from the
> engine compartment.  If I rev the engine, it stops, and it stops if I
> run the engine for 30-40 seconds.  The noise has been getting
> progressively louder as the temperature gets colder.  I haven't been
> able to get to the engine, before the screeching stops, so I can't
> identify where it is coming from.  Is the low idle related to the
> screech or is the screech related to the low idle?
>
> Any ideas what this problem could be?
>
> Thanks,
>
> Stephen Jones
> '87 Westy
>

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