Fast Idle after replacing 929 timing belt

Well after replacing broken timing belt on 1988 929 I thought I was OK.
Good compression tests, engine runs. Good power on the road. I thought
that I was very lucky not to have any damage.

BUT its now idleing at about 2500 to 3000 RPM even when warm. Any ideas
on what could be causing this, what to look for?

Thanks, Bob

In article <47a8631f$0$1124$(E-Mail Removed)>,
"Bob" <(E-Mail Removed)> wrote:

> Well after replacing broken timing belt on 1988 929 I thought I was OK.
> Good compression tests, engine runs. Good power on the road. I thought
> that I was very lucky not to have any damage.
>
> BUT its now idleing at about 2500 to 3000 RPM even when warm. Any ideas
> on what could be causing this, what to look for?

Sounds like the sensor that watches the engine temp. and reports it to
the computer control unit is faulty or the wire has come off... Some
troubleshooting will be required, but the replacement sensor is cheap
and also reasonably easy to access. Start there.

I'm suspicious, since replacing the timing belt likely involved removal
of all sorts of sensor wires that were in the way. One got missed, or is
now damaged... or the sensor itself has just failed.