Will do. Thanks. That alternator is less than 2 years old (4,000 miles). When I was cleaning up the fire damage, I bombarded that connection with contact cleaner. Heck, maybe I made it worse because it is crusty looking.

I do have a backup alternator that I suspected was bad (that's why I have a newer one) but as it turned out it was a bad regulator plug. So I can always try swapping again. Oh BTW, as you could imagine, that cable gets very warm...about 100 degrees more than the surrounding area (I have one of those laser thermometers).

Question: Do you suspect the sparking is caused by something that has something to do with the alternator or some other source?

 

I'd have to have a closer look at it to make a good determination.

Though, given what you have observed temp-wise, I might be tempted to replace that wire with something slightly heavier gauge...... Keep the heat down....

 

I'm assuming the temp was higher on that cable because all that sparking was heating it up. That cable wouldn't be easy to replace. It's buried in a sleeve that's packed with a bunch of other wires that is buried between a bunch of stuff. I might be able to fish tape it through or if all else fails, reroute it. What does the connection inside the PDC likely look like?

BTW, My AC does not blow cold air.

 

I think on the PDC end, it's just another ring terminal. So far as I know, that wire is a straight shot from the alt, to the PDC, no other connections, and no splices. (would have verify that with the wiring diagram though....)

When is the last time your A/C worked?

 

Yes, you're correct. That cable goes pretty much straight from the PDC to the alt. Just has that sleeve tunnel it goes through on the way there.

My AC was working the day of the fire. That's what led me to believe the AC might of had something to do with the cause of the fire because it was the first time I ran AC since last summer, 2024.

 

A/C wiring is on the other side of the intake though, isn't it?

Two circuits need to be operating for the A/C to work, the pressure switch circuit, and then the feed to the compressor. If either one is compromised, no A/C.....

 

I believe it is on the other side but not certain. The only damage to the AC that I know of is the tubes and it looks like just that outer rubber got scalded.

 

One of 'em is a high pressure line.... if you have gauges, throw 'em on there, see what your pressures look like. If there is still good pressure in the system, then likely just need to find the damaged wires.

 

I replaced the current alternator (2 years old, 4,000 miles) with the alternator that was on previously (10 years, 20,000 miles). The previous alt was not original equipment, but it has little use, it was very clean and I had new brushes and terminal block on it so it's in excellent shape. I didn't want to mess with the current alt. It was pretty crusty around that terminal/insulator from that fire.

Anyway, after cleaning/repairing terminals and wires, etc. I got the backup alt installed. I did NOT replace the alt-pdc cable. I just cleaned up the ring terminal on it. Result: zero sparking, voltage nice and steady.

I've had enough shade tree mechanic for one day. Gonna hit the showers. And once again HY, thank you for leading me in the right direction. You, Sir, are appreciated as is this entire community. Up next: cruise control then AC. I'll have to pay someone for the AC cuz I don't have any gauges. Been thinking about converting the Freon anyway cuz it's still the original R12. It worked (prior to the fire) but it isn't as strong as it once was.

I'm curious...which sensor is this? I'm guess it's a temp sensor for the coolant?? It had fire damage as well. About 1.5" was missing insulation. Got it repaired. Seems to be working. At least I haven't noticed anything out of the ordinary.

 

can't tell from the pic really, but, if that's a one-wire sensor, it's for the temp gauge in the dash. If it is two-wire, that's temp sensor for the PCM.

Happy to help my friend.