Re: Pull Fault codes on '89 100? Out of luck?

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

Jeff,
There's a TSB 91-02 for this car that describes the need to have the Fuel
Injection Control Unit and the Ignition Control Unit matched according to
part numbers.  Some cars had mis-matched units installed at the factory.  I
installed a new FI computer in my 89 and created the mis-match myself.  One
problem caused by mis-matched units is you won't be able to display fault
codes.

You might want to compare the part numbers off both these units and check
them against the TSB.
I got the TSB off the AllData CD-ROM, but don't have a copy with me now.
e-mail me the P/N's if you want me to look it up later.  The FIECU is
against the outside wall in the front passenger footwell.  The ICU is
against the wall in the driver's footwell.
  
In my case the car seemed to run fine for about a year with the replaced
ECU until suddenly it wouldn't and no one could figure out why until an
alert dealer mechanic figured out the mis-match existed.  Replacing it with
the correct P/N, bought used for $185, fixed everything.  

The original FIECU went bad for no apparent reason...it was like that when
I bought the car used.
I talked to Ned Ritchie in the course of trying to solve the problems and
he said at about the time this car was made a substandard batch of circuit
boards made it's way into these units and various problems were caused
because they were not designed for the environmental extremes automotive
parts are subjected to.  In my case, the original FIECU seemed to cause
lack of power at all times and other problems that got increasingly worse
during cold weather. 

HTH,
Dave C.


David Conner  Columbus, OH 
'87 5KS,  '89 100E, both w/ Boge TG
'86 4KCSQ w/Koni's & freeflowin' exhaust...Yeee Haaa!