2G '96 Talon TSI Alternator Not Charging

[1slowhatch]

Recently got the car running. Purchased it with a broken timing belt. All new timing components, seals, cas, etc. Car runs and drives well, idles smooth, no check engine lights... however, it appears the alternator is not charging. I did have an alternator warning/battery light on first start up with the head. I noticed the positive terminal on the battery was loose, so I replaced it. The light went away. I assumed everything was fine. However, I have checked the voltage at the battery and the output stud of the alternator with the engine running, I never see more than battery voltage (high 11's to low 12's). The battery is approx. 2 years old and has passed a load test.

What could this be? The alternator itself looks like it couldn't be more than a year or 2 old. It is plugged in, the charging output is tight.

 

[1slowhatch]

Any ideas? I still can't get it to charge. Tried bypassing the charge wire with jumper cables, added a ground to the alternator. Had the battery warning and A/T temp idiot light on for a minute or two today, then went off.

 

[Gsx-Dude]

Sounds like your alternator regulator is toast.

 

[1slowhatch]

Any way to test it on the car?

 

[Gsx-Dude]

You have to remove and disassemble the alternator to test it.
Here's a good manual of how to test it: http://www.galantvr4.org/docs/1g_charging_starting_system.pdf

 

[Chumpaumpalumpa]

Any way to test it on the car?

Take it to Autozone or oreilly and they can test it in car. Get a new alternator. The auto one is plug and play for the 5 speeds and comes with 10 extra amps. woohoo

 

[1slowhatch]

My car is an automatic, so I supposed I already have the larger alternator.

 

[1slowhatch]

I believe I have this solved. I swapped out the alternator for a 90 amp reman unit and it appears to have fixed the problem. 14v+ at idle now, no more dead battery, haven't seen the battery warning light in a while.. I do have a check engine light.. P1400. It also runs a bit "jumpy" in the mid RPM range while driving. I've read this can be caused by a bad MDP sensor, but more commonly a boost leak problem!? I double checked that all the intercooler plumbing is hooked up and tight, checked for loose vacuum lines, etc. I do think that the factory BOV is leaking much earlier than it should, could this be causing the problem? When foot braking the car, I can clearly hear a boost leak, which sounds like the BOV releasing air after I see boost "come up" on the factory gauge.

 

[PlanZero]

The first mod you should always do on a 2g is upgrade the bov.

 

[chrysler kid]

If you're auto and foot braking it the engine builds boost faster than just revving it in neutral. So it should just sound like you are building boost.

That being said though as mentioned thr plastic factory bov is not good at holding boost. Even my fake type S ebay unit holds boost much better than stock.