Strange intermittent situation, '87 5KCSTQ

[MHLIGGINS@aol.com]

    The situation is odd. I have a few glitches that tend to group together 
and hit the quat at the same time. I'm trying to figure where the commonality 
is...
    Car is an '87 5KCSTQ, engine is a 10v I-5 with the K-24 turbo from a '91 
200 automatic.
    Main symptom (that I've noticed) is that the power gets cut 
significantly, which I suspect is the timing being turned down. When things 
are "right" the car runs very well and goes to 1.5 bar of boost with the 
stock ECU and wastegate spring.
    When it's in a "sour" mood the power comes and goes. The ECU always kicks 
out a 2312 (temp sensor) code, it sometimes lights the "pads worn" light, and 
is sometimes VERY DIFFICULT to get started. When it is in the slow-start mode 
it often sounds as if it is running on only one or two cylinders for a while, 
then eventually gets all five going.
    It does not seem to be dependent on outside air temp or engine 
temperature.
    I've swapped ECUs, wastegate springs, and checked the ground wires I know 
about on the engine (intake to ECU, head to firewall, and driver's side motor 
mount.) Cleaned all of them by using a file to scrape down to bare metal. 
I've rechecked the solenoid that controls the fuel (and CAN'T think of the 
proper term for that thing at the moment...) with a dwell meter -- several 
times. I've checked every single vacuum line in the system, several times, 
with a vacuum pump. Plus other stuff that I can't think of at the moment 
'cause it's way past my bedtime.
    At one point I thought I might have a wire with an intermittent open 
circuit between the temp sensor and the ECU, but I can't figure out how that 
would tie in with the brake pad light and the hard starting.
    So -- anyone able to think of some place where these items overlap? I 
suspect I'm missing something very simple, and I'm gonna be real pissed when 
I find it. But I'd rather be pissed for a little while and have the car 
running like it should than continue to be pissed because it's an 
intermittent dog....

    Thanks.
    --ml

BTW, I was at the drag strip last night. Knowing how well this car runs on a 
good day, I can't wait to sort it out and go back to compete....!!!