Last night I had something odd happen on the way home. It's an hour drive at highway speeds with nothing unusual - the kind of miles that I would consider good for a vehicle. About halfway home all the warning lights (except the bottom right two which do come on when the ignition is turned to ON before start), the shift light, and the buzzer came on and stayed on. Temp, speed, RPM, and boost indications were normal and stayed that way. The performance and sound of the car also remained the same.

My first thought was of course CPU since the above symptoms are all tied together through that unit (I have done the resoldering which fixed the light/horn problem and I did remove the old solder as suggested). Since the car seemed to be doing fine I did some troubleshooting as I was driving. What I found was that if I got the RPMs high enough (around 5,500 either by speeding up or simply pushing in the clutch and revving up) the lights would go out and the buzzer would stop. After a few seconds back down at normal RPM the lights and buzzer would come back on. That leads me to think alternator output as another possible cause.

One other oddity, though perhaps unrelated, is that my hot start problem has come back. I had been dealing with it quite well by revving just before turning off the key to hopefully dry the chambers before the engine stopped rotating (similar to the way you'd shut down an small aircraft engine.) After this lights problem it doesn't seem to matter how I shut down, I'll be flooded when I try to start again.

Does anyone have any suggestions for anything else those symptoms could point at? Anything I should test? I guess it's possible that she's just punishing me for riding my motorcycle this week since the weather has been so nice. ;)

Thanks.

 

bad alternator. What was your voltage when this was happening

 

I don't have a way to read that while driving and have not had time to do any further troubleshooting since it happened. I recently fixed one major problem (or I thought it probably was) with the alternator. I found that the alternator had previously been repaired/replaced when it was put it back on the power plug was in the vertical position and the intercooler was mashed down on top of it. Over time the insulation was ripped and made it so that if you put a multimeter on the intercooler and the intake manifold you had 12 volts.

Anyway, I'll check the voltage next time it happens. Thanks!

 

ah a Turbo- no voltmeter...

 

Yep, I should have specified that! She's an 87 TII with a fresh tune-up and mods to speak of.