help! 2004 Jetta ALH won't start.

[NeXTstep guy]

My 2003 Jetta TDI won't start. It's at the local CanadianTire right now and I'd appreciate some TDI guru advice...

My wife drove the car twice yesterday and it was fine. The third time, it wouldn't start, there were cranking sounds, but no starting.

We checked the anti-shudder valve and that is not the problem.

It might be battery related, but I am not sure about that part. (Sorry for the long battery story...)
- when I first looked at the battery, it was a bit below 12 volts. This is on a 7 year old interstate 130Ah battery. We haven't had any starting problems at all until yesterday.
- We got a boost (donor car was running), drove 15 minutes to the in-laws to borrow the battery charger. It started fine at the in-laws and drove another 15 minutes home.
- I looked at the cells, and only 1 cell was a bit low.
- We hooked up the intelligent charger overnight and it stopped charging sometime in the night. When I disconnected the charger, my voltmeter said it was at 12.25 (12.29?) volts.
- I tried starting and it would crank, but not start. My odb reader said that my battery was at below 12 volts. (Sorry don't remember voltage).
-get another boost. Could not start with donor car off. When donor car was running we started.


I am at Canadian Tire right now. They attempted to boost with their battery and had trouble. Getting crank sounds, but no starting.
The plan is to check out the charging system, and to replace the battery.


Does that make sense, or is there anything else we should try? (The InterState battery is a 85 month warranty battery and we are somewhere around the 90-95 month mark.) I can't figure out why I can't start it, aside from the checking the anti-shudder valve.
RWW

 

[oilhammer]

Well it either cranks enough to start or not. If it will not start because of some fuel or engine management related problem, then cranking/battery/charging is not the issue.

Do this:

Turn the key ON

Does the Glow Lamp come on and go out?

Does the Check Engine Lamp come on and stay on?

 

[NeXTstep guy]

I'll check those things in a bit. The mechanics have pushed my car in to look at it.

I'm Ok with the the battery replacement and check on the charging system.

If I can get it started, I can bring it back home and borrow the in-laws car for a week as they are away.

Thanks for your reply. I'll keep you guys posted.
RWW

 

[NeXTstep guy]

Good news! The mechanic tells me the old battery was internally shorted. He said that when the old battery was still connected, their diagnostics said that the alternator and other things were dead as well.

When they put in a new battery the new car started up fine.

The new battery is an MotoMaster Eliminator Ultra AGM-type battery, 94R, with a reserve capacity of 140Ah. The warranty is a 5 year replacement. (This is in comparison to my previous Interstate battery that wasn't AGM, but had a reserve capacity of 130 (I think) Ah and a 3 year replacement warranty.)

More info later tonight.
RWW

 

[oilhammer]

So it wasn't "cranking" like you said in your original post then.

 

[miningman]

Well a running tdi , with a good alternator shows about 14 volts across the battery terminals. With engine off, this voltage on a good battery drops to about 13.0 -13.2 volts. in my experience anything below these values indicates a defective alternator or battery that is on its last legs. At 12. 3 volts , i'd say you definitely need a new battery and make sure all grounds and connections are clean and tight.

 

[NeXTstep guy]

So it wasn't "cranking" like you said in your original post then.

Hmmm. Maybe I should attempt again explaining things....I put the key in the ignition, and turn the key. The car makes a turning-type sound from the engine, like something cyclic, but there is no car sputtering/clattering/running sound. (I don't recall what lights turned on on the dash, but there were dash lights, the daytime running lights turned on, the "dome" lights turned on, and the radio looked like it turned on.")

Is it fair to describe that as a "cranking" sound? I hope what I described was "cranking"-type sounds. My apologies if I was unclear.
RWW

 

[NeXTstep guy]

Well a running tdi , with a good alternator shows about 14 volts across the battery terminals. With engine off, this voltage on a good battery drops to about 13.0 -13.2 volts. in my experience anything below these values indicates a defective alternator or battery that is on its last legs. At 12. 3 volts , i'd say you definitely need a new battery and make sure all grounds and connections are clean and tight.

Thanks for the voltage ranges. I had a handy battery brochure and it showed similar numbers that you mentioned.

I was suspicious of the battery given the age of the battery. I don't have the tools to test the specific gravity of the battery fluids. One cell was a bit low, but still had enough water to cover the cell. I added some distilled water to bring it a bit higher.

After charging overnight with the intelligent charger, I too expected a 13V+ value, not something in the 12.2x range. When I attempted to start the car (putting load on the battery) it dropped to the 11.x range. At that point I really suspected something was wrong with the battery.

Academic question: If you have a fully charged good battery, and your alternator is bad, can you start your car? What would a car with a bad alternator look/run like?
RWW

 

[BobnOH]

Yes it will start and run. The battery will quickly lose it's charge.
All the circuits in the car are connected to the battery, the alternator does nothing more that charge the battery. It does need to turn on and off to keep from overcharging. If it overcharges you can end up with a bad alternator and battery, it can even ruin wires/connections.

 

[willyworm]

7 years out of any battery is doing pretty good.

Sent from my SM-G930V using Tapatalk

 

[turbovan+tdi]

Hmmm. Maybe I should attempt again explaining things....I put the key in the ignition, and turn the key. The car makes a turning-type sound from the engine, like something cyclic, but there is no car sputtering/clattering/running sound. (I don't recall what lights turned on on the dash, but there were dash lights, the daytime running lights turned on, the "dome" lights turned on, and the radio looked like it turned on.")
Is it fair to describe that as a "cranking" sound? I hope what I described was "cranking"-type sounds. My apologies if I was unclear.
RWW

Cranking is when you turn the key and the engine turns over, enough to start if it could. If it doesn't "crank" "turn over", then that's pretty easy to diagnose. If it does turn over but won't start, that's where the fun begins.