alex Dork
8/5/10 11:22 a.m.

My search for a long-distance commuter for my Better Half has started pointing me toward TDI Jettas. It would suit her purposes well for her 100+ mile commute: nice interior accommodations, good mileage, not mind-numbingly boring to drive.

We have 3 friends with Jettas: one GLI, one A4 TDI and one A5 TDI. None of them report any repairs that I'd consider out of the ordinary for a modern car, ie: they're high-mile cars with various computer systems that crap out and need to be replaced to the tune of $1000 or so. Pretty standard in my opinion.

What's worth knowing about A4 TDI Jettas? What should a buyer look for?

Drewsifer HalfDork
8/5/10 1:15 p.m.

I've got a 2005 Golf TDI. Something to pay attention to is during the A4 model they switched engines. I don't know a whole lot about it, but apparently it was around 2001-2002. The early engine doesn't make as much HP, but gets slightly better MPG. However the early one is not so down on power its a dog.

Also ask about the fuel pumps on high mileage ones. VW uses a low pressure fuel pump at the tank and then a high pressure one at the engine. When the low pressure one goes, the high pressure one almost always does. If they haven't been replaced and you're getting around 150k, it's a pretty expensive job. However I love my TDI and won't ever get rid of it. Great reliable cars.

Ian F
Ian F Dork
8/5/10 1:42 p.m.
alex wrote: What's worth knowing about A4 TDI Jettas? What should a buyer look for?

Maintenence records. German cars in general don't suffer neglect and appliance-treatment well. TDI's even less so.

One problem I've discovered about non-enthusiast owned TDI's is the owners buy the cars loving the MPG, but then balk when it comes to maintaining the car per the service recommendations. Oil quality in these cars is critical to them living a long life. Fortunately, it has become easier to find in recent years - I can now buy VW-rated Castrol Syntec at Pep Boys vs. the first 5 years or so when I bought oil at a VW/Audi dealer.

A lot of people have trouble wrapping their heads around replacing the fuel filter every 20K miles. However, if you remember the fuel also serves to lubricate the injection pump, then it makes sense you want to make sure the fuel is clean.

One of the first things to look at with a used TDI is the coolant tank. The coolant should be pink and the tank clean. If not, it means some idiot put green crap in their coolant and effed it up. My car has only received VW coolant and distilled water. After 7+ years and 224K miles the coolant tank still looks like new. Considering the coolant is only changed every 100K miles (w/ the TB) it's a small price to pay.

Cars built from '03 use 100K mile timing belts. Most replacement kits sold use 100K mile belts as well. TB kits run around $300 and require some special tools to do properly, but it's not a terrible DIY job.

A3 & A4 (and the B4 Passat) TDI's from '97 to '03 have the ALH engine. From '04 they use the higher injection pressure PD engines. IMHO, the ALH is the one to have. It's the easiest to maintain and modify for more power and also gets the best mileage. It's downside is it's not as 'clean' as the newer engines and has more of that diesel clatter. Read the FAQ at the top of the page. It'll tell you anything you want or need to know about a TDI.

I bought my car new fully expecting to do all service to it and to this day, the only person to ever turn a wrench on it has been me. Fortunately, the car has been stone-reliable.

alex Dork
8/5/10 1:48 p.m.

Experts: that's why I ask this board.

mistanfo SuperDork
8/5/10 4:14 p.m.

Love the wife's '03, even if it is a two pedal. Great for hitting the DC beltway. Comfortable enough that I won't hesitate to take a 17.5 hour day in the car, and I don't know of another car that i can say that about. Best tank was 48, worst was 34, which was A/C on full, and averaging triple figures. 140,000 and she's on her second set of brakes, third set of tires and second timing belt. Many oil filters and fuel filters, as well as air filters and cabin filters (the latter is a pain). Easy to maintain overall. Had someone do the timing belt, since I was hesitant to destroy the head. Needs a transmission flush sooner than later.

John Brown
John Brown GRM+ Memberand SuperDork
8/5/10 4:31 p.m.

My dream TDi would have a 2005 body and a 2001-2002 ALH engine. It would be slower but have fewer issues.

alex Dork
8/5/10 5:56 p.m.

John, I'm interested to hear your service writers' opinion of these things.

Jensenman SuperDork
8/5/10 6:43 p.m.

I got away from VW in 2001 (whew! not a moment too soon, I was lucky to escape with my sanity reasonably intact) and the 1990's cars were, to put it mildly, problematic. There was a recall which involved replacing the intake manifold (!) along with the usual litany of weird electrical problems. The engine will pretty well destroy itself if the TB breaks, particularly at highway speeds. No direct experience with the '01 and up cars, though.

nderwater Reader
8/5/10 8:47 p.m.

Our 2001 Jetta TDI had some electrical annoyances, but was always reliable and was a very practical commuter car (though slow and not particularly exciting to drive).


John Brown
John Brown GRM+ Memberand SuperDork
8/5/10 9:16 p.m.
alex wrote: John, I'm interested to hear your service writers' opinion of these things.

The way I like to put it is you need to be wealthy or an exceptionally detail oriented technician to keep a TDi well cared for for the long haul. I think the MKIV is the heartiest of VWs and the best TDi is an ALH car. Pumpe Deuse engines are not engineered for 250K mile service. They eat cam followers like they were Baconators. There are a lot of wiring connection issues from low priced suppliers, a lot of that was resolved in 2002 but certainly not all.

Buy a clean unmolested well maintained car that has been serviced every 5K miles with Castrol Syntec and you will be fine.

Ian F
Ian F Dork
8/6/10 9:27 a.m.

IMNSHO (since I own one), the best TDI to buy is an '03. It's the last year for the ALH engine and was towards the end of the Mk IV production run, so [in theory] most bugs had been worked out. Most cars were built in Mexico with the wagons (what I have) coming from Germany. That said, evidence the Mexican cars are inferior has been inconclusive at best.

Some other notes, mainly with regards to my own experience:

I have the upgraded Monsoon sound system. For a stock system, sound quality isn't bad (better than the Harmon-Kardon systems in our MINIs), but radio reception is crap and upgrades can be tedious if you want to maintain steering wheel functions. I would like to upgrade to a better system with MP3 and aux-input, but keep finding other things to spend my spare money on. The Vortex is better for this info than tdiclub.

Replacing the driver's headlight bulb will make you scream.

I've resisted the urge to do any sort of WVO conversion. For me, the amount of money saved is simply not worth the additional time required to do it properly and safely (for the engine). I'd be more interested in converting WVO into BioD, but again - time & space required. And then only because my home heating system could burn BioD as well, so additional cost-offsets can be had.

In all honesty, I tend to NOT recommend a TDI to most people. I have the space (house w/ garage), tools (lift, special service tools & VAG-COM) and back-up cars to service the TDI when needed w/o rushing anything. Because of this, the money saved on fuel isn't spent on keeping the car running. If you have to pay a TDI specialist to service the car, it may not pay.

Dealer service seems to be hit or miss. As mentioned, when I bought my car in '03, there were far more horror stories about dealer service than their were about dealer techs who knew what they were doing. It was this reason that I invested in the tools required to work on the car myself. My first TB change probably cost about $1000 in parts & tools. It will take at least 2 TB jobs for the tools to pay for themselves (although VAG-COM paid for itself much faster). With the increased popularity and acceptance of TDI's in the current line, I'd like to think the dealer techs are getting more/better training these days.

I would look for a TDI on the tdiclub forums. You may pay a little more, but it's more likely the car has been cared for.

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