weird goings on 99 expy

[Kermit]

OK had an incident today where my truck stalled and wouldn't start without a jump. Battery light came on intermittently yesterday. Wasnt on when I started the truck, then after driving a short distance the light came on. Same thing every time I started it and drove yesterday and today. Guys at advanced auto think alternator.

Today drove a short distance, under 10 miles, same thing, no light when started, drove like a mile and it came on. Had a Dr appt, came out started right up, went next door to get scripts and while idling in park motor was running kinda rough, battery light was on, then i got like a surging idle that actually rocked the truck a few times then it died. Hubby put a meter on the battery post and got a 12 volt reading. When I tried to start it after the stall ALL gages spiked then went back to normal, cranked then dies, no start. Hooked up to jump and started right up... Drove the less than 5miles home, no rough idle, battery light on but no stall on the trip home.

Hubby doesn't think alternator since the battery had full charge. I know I have some electrial gremlin somewhere cause sideview mirrors will sometimes be moved, odometer goes in an out, sometimes lit sometimes not, sometimes goes out when I turn on lighs, sometimes not. Driver window even opend one night, and that mirror moved pointng all the way outwards. Weather doesn't seem to play a part with my gremlin, happens in all conditons. Mileage just a tick over 200k... I think that's everything...

Thoughts?

 

[Bedrck47]

Have hubby check the battery voltage with nothing on Then start and check voltage Then rev engine to 1500-2000 RPM's and read voltage. Also check all electrical connections on Battery and Alternator for looseness and or corrosion.
Post the above voltage readings

Rather than Guys at Advanced Auto Thinking what could be They should have checked it and that way they would know.

To be honest I don't trust people that say THEY THINK the problem is I want someone that can say for sure what the problem is.

The odometer light is a normal problem on the 1st gen expys and is a simple fix Plenty of videos on youtube on how to fix it

 

[Bedrck47]

How old is the battery. Doesn't matter if a battery shows full charge, What does matter is what the battery does when it has a load on it.

 

[Kermit]

Battery was in the truck when we're bought it so maybe 2ish years old, dude said just replaced before we bought it. Yeah I was kinda ticked advanced didn't just check and assumed the problem was alternator.

 

[Kermit]

Ok, prestart 12.42 immediate post start 12.14, revved at 2000 rpm 12.10. All connections look/feel good but hard to see right side of alternator hard to see in lake effect snow... Will get better inspection tonight when he can pull it into the shop. No corrosion noticed on battery ports, no corrosion noted on alternator wires but all are in those plastic casings. Casings didn't look crackd or marred at all.

 

[Bedrck47]

at 2000 rpms you should be seeing 13.5 to 14.5 volts Check the belt tension on the alternator. if belt tension is good I would say the alternator needs replaced.

Advanced may be correct but testing is the best way to check it.

You may be able to get an alternator on e-bay for less than advanced unless your in a hurry

 

[Bedrck47]

Just sent you a PM

 

[stamp11127]

One more test to prove alternator failure. Since it is a northern vehicle that enjoys salted roads in winter it would help to prove the ground isn't the problem
Engine running @2000rpm, red lead of meter on alt output post, black lead on alt case. Scrape case with lead to make sure it is a good connection. If reading batt voltage then it is a failed alt.

 

[Kermit]

Thanks hon. Will do... Partsgeek had some decent prices, like $80-100.

 

[stamp11127]

There is another possibility but before getting into that I would have the current alt tested after removal.