My dash indicator lights are behaving oddly. when I turn the car off and remove key, the Battery and oil light come on. I've changed oil, checked alternator mount and belt tension. anybody got an idea?

Tom

I had the same issue with dash lights,
found the main alternator cable had grounded itself,
the exciter wire and the oil pressure wire.(right beside crank pulley)
I was able to cut the bad insulation away, solder on
new wire for the exciter and oil pres. (reused the connector),
re insulate the main wire.
Started it up and the alternator was good to go.

All thanks to brickboard and Tom's post

thanks all. Will get on this pronto.

Tom, I'll add my two cents too. You'll find the problem very close to the alternator, if not in the alternator. Adding to the similar predictions, you need to figure this out soon, and not park the car in the garage until you do.

My first step would be to disconnect the battery. Then I'd carefully disconnect the alternator and oil pressure sender and examine that wiring up to where it clamps at the front crank seal cover.




--
Art Benstein near Baltimore

Some days you're the bug; some days you're the windshield.

Look at me NOT blaming the my arch-nemesis the alternator ground wire for a problem that could be the alternator ground wire. I am very ashamed of myself.

Well, I suppose it could be a broken ground. But I'd have to think there'd be a leaky diode helping it with those symptoms.


--
Art Benstein near Baltimore

The quickest way to double your money is to fold it in half and put it back in your pocket.

I started seeing this when the wire bundle behind the alternator shorted out (that involved the oil sender's wire, too). Actually, it started a fire by igniting oil leaking from the oil pressure sender, so look very carefully there.

Also, check your battery voltage as the car stands overnight -- a symptom that I was seeing before the short and fire was evident was that my battery was running low overnight but only in retrospect did I realize that this was an early warning -- the short was draining the battery.

P.S., I have a series of posts on this forum, a few months ago, about fixing the aftermath of that short and fire.

Were this an earlier, biodegradable wiring harness car, I would say you have a problem with the wiring by the big, gray, firewall plug. However '89 is not prone to that problem. Still, as suggested, check the wiring by your alternator. While you are there, check the ground wire that goes from the alternator case to the mounting bracket bolt at the block.

There are metal clamps on the crimp edge of the firewall where your harness is hung. Check around that big gray plug for damage. Recently I had a 90 that would occasionally not turn off. I found that in replacing the crank position sensor, the owner had done some "rearranging" of the cables and harness at those metal clips. The clip had actually cut through the harness sheath, causing a short.

Check your fuse box thoroughly. Make sure you don't have any errant wires loose, or added in. I've seen problems from stereo connections stuffed under fuse ends. Frayed wires bridge fuse contacts causing problems.

A bad ignition switch block will often make itself known via accessories that don't work reliably like the heater fan, headlights (on later cars), rear defroster and radio.

i think you have a short. since your oil pressure light is coming on the most logical place to look is the harness of wires underneath the oil pressure sender and behind the alternator.

i will wager the insulation is abraded shorting 2 or more together.

If you jiggle the key around when mostly removed do the lights go off? If so, ignition switch (electrical portion) possibly conspiring with a worn barrel (mechanical portion). I would bet on it just being the switch that is the real culprit. Not hard to change on the pre-knee bolster cars but apparently quite challenge if you has it.

I seem to remember a thread long ago about leaking diodes in the alternator causing this as well but I would think the lights would go off shortly after the ignition was turned off.