Last post on Jun 09, 2013 at 7:21 AM
You are in the Volkswagen Jetta
What is this discussion about?
Volkswagen Jetta, Biodiesel, Diesel, Sedan
#1684 of 4751 Re: VW Jetta TDI 2001 [nancydemello]
Feb 04, 2008 (6:25 pm)
Charging a battery while it is installed in the vehicle using a hi-power charger may perminently damage the onboard computer. (and other devices) Lets hope this is not what happened to your car. If your "new" battery was dead and had to be charged up... then you purchased a bad battery. A lead-acid battery which has been discharged to the point of being "dead" will become internally damaged. Its lifespan will be severely reduced.
The best battery to buy is one that is stored on the shelf "dry" with no acid in it. This way, it is fresh and truly "new" when the acid is added before installing in vehicle.
As for capacitors becoming "overloaded".... I am college-trained in electronics and can tell you that the only way to damage a capacitor is to apply too high a voltage... at which point it will explode like a firecracker. I do not think this is your problem.
Your only real way to diagnose the problem is to hook your car up to a diagnostic computer. (Like a laptop computer with VagCom)
#1685 of 4751 Re: 2002 tdi jetta doesn't like to start [blundy]
Feb 04, 2008 (8:18 pm)
Just putting my two cents in re: the re-flashing of the computer after a battery failure/disconnect. If you read the manual in some older TDI's (older as in pre-2004 for sure, not sure how far back you'd need to go but it is mentioned in my '05 manual), the newer radios, etc. will "remember" their vehicle in this circumstance. Older vehicles required you to enter the unlock code when this happened. Not sure about the vehicle completely losing the info though, that sounds like someone wanting to make some easy money.
#1686 of 4751 Re: 2002 tdi jetta doesn't like to start [bpeebles]
Feb 06, 2008 (9:00 pm)
Not sure what happened to last message but will try again.
Thanks to all who responded to my inquiries. I appreciate the advice but none of it sorked so far. I am aware of the glow plug light ...now. However, after reading through the manual 3 or 4 times cover to cover, i cannot find mention of the light. The only thing in the manual about diesel is a 3 page spec sheet in the back. It's like it is an afterthought. I tried the key in the door and one in ght ignition. Nothing. The immobilizer light is blinking to show me the car thinks it is being stolen. No fuel to the engine is an indication the immobilizer is not turning on the pump. Typical of the system.
It was not a problem of difficult to start in the cold. It has always been a problem of it just not starting at all. The only commonality is that the battery went dead dead dead. Even the little red dash lights would not even glow. I am going to spin a note off to VW techies and see if they have any bright ideas. If I learn anything, I'll post it. Thanks again.
#1687 of 4751 Re: 2002 tdi jetta doesn't like to start [blundy]
Feb 07, 2008 (9:53 pm)
I think we solved the problem. A few months ago, (6 or 7) I had a new key cut and programmed for the VW. That was because when I bought the car, it had only one key, a flip out laser cut key with the transponder in it. When the battery went dead, I tried my original key and the immobilizer thought it was the wrong key and it was being stolen. When VW put the new codes in my new key, they actually made the second key the master key. So, I put the new key into the ignition and turned it on and left it sit for 20 minutes with key on, not trying to start it, Went in the house for a cup of coffee and came back and the new key started the car and it runs just fine. Then I want back and got the old master key and it runs on that one too now. I have no idea what that computer is thinking but it reminds me of Hal from 2001 space odyssey. I had tried the new key without letting it sit and read itself and no start. I guess that's the VW preferred way of reprogramming the system albneit with the new master.
#1688 of 4751 Re: 2002 tdi jetta doesn't like to start [blundy]
Feb 08, 2008 (7:24 pm)
It is good to hear that you resolved the problem. It sounds as if you must have tried a lot of things before you get to that point.
#1689 of 4751 Re: 2002 tdi jetta doesn't like to start [bpeebles]
Feb 08, 2008 (8:53 pm)
Sure did but thanks to this forum and the advice that the jokers at the dealerships might just be worong, I decided to keep trying every hint I could find. Finally stumbled on it. Watch out, Hall is watching.........
#1690 of 4751 Re: Sluggish '05 TDI [inlarry]
Feb 09, 2008 (5:01 pm)
I don't know if you have gotten your problem taken care of yet, but when you say it runs smooth up to 2000 rpm, but then no power, and some light jerking when you try to accelerate, it sounds very similar to my past experience which ended up being the fuel filter. The first one was at 18,000 miles. I was surprised when it needed replacement again at 27,000 miles. Only thing I can think of was that I possibly was unlucky enough to have filled my tank right after the station had it's tank refilled, and a lot of debris stirred up from the bottom of their tank ended up in mine.
Anyway a new filter took care of it.
If that is what it is, it won't be a warranty item, so you will pay the dealer unless you do it your self, which isn't difficult. Best thing you can do is buy a Bentley service manual for your model. They aren't cheap, but saving yourself one dealer service will more than pay for it, and after that it's all money in your pocket each time you are able to use it to do your own service.
#1691 of 4751 Re: Sluggish '05 TDI [sandman52]
Feb 09, 2008 (5:10 pm)
Actually it turned out to be a combination issue...about 90% fuel filter, and a faulty MAF sensor. The dealer's doing the sensor, but replacing the filter myself fixed most of the problem.
#1692 of 4751 Re: Sluggish '05 TDI [inlarry]
Feb 09, 2008 (5:39 pm)
..."As stated before, if I had to guess, it would be the MAF. In addition anyone one anywhere anytime can get a batch of bad fuel. "...
Glad we could help in the diagnoses.