89 100, difficult starting, poor running

[David Conner <conner@cfm.ohio-state.edu>]

When I left the car at the shop the mechanic laid out an interesting theory
of what is causing the engine to start and run poorly.  The coolant
temperature gauge  doesn't work.  He suggests the reason the coolant warning
light is on is because the diagnostic system is trying to tell me the car
can't run properly without the coolant temperature sensor's input to the
ignition computer.

He also said it was a bad idea to unplug the oil pressure idiot light
sensor, which I'd done because it malfunctioned...staying on all the time. 

He also suggests, as anyone paying attention to this list would know, that
the ISV could be the culprit.

I'll be interested to see what he comes up with once he has a chance to look
at it, which could be a few days.
The idea that these sensors provide input to the computer makes sense.
It sounds so obvious I think I deserve a kick in the a** for not thinking of it.

What sayeth the list?  Is it critical that all the engine sensors work?
Dave Conner, Columbus OH   e-mail:  conner@cfm.ohio-state.edu   
'87 5000S     '89 100