1998 VW Jetta TDI

Engine: Turbo Direct Injection Diesel, 90hp
Color: Silver Arrow
Options: ABS, power tilt/slide glass sunroof, AC, metallic paint
Warranty: 24mo car, 10yr/100K drivetrain, free service for 20K miles.

     Great fuel economy!  And goes 650+ miles per tank.
          About 42 to 44 mpg normally, with a high of 51 (when I really babied it!).
          Lowest road trip MPG was just under 40 on a trip that was nearly entirely 80 to 90 mph.
          Absolute worst was 30 (I think) towing a 16' Hobie Cat on the interstate.  Towing normally gives 35+.
     It's fast. 100mph is easy to reach and 110 is almost possible.
     Good ride.  Better than previous VW's by a long shot, and lots quieter, too.
     The stereo is really good for a factory system
     Great power for a Diesel.  Also it starts wonderfully, even in the cold, and there's almost no smoke.
     Everything works!  This is the whole reason we got it... 

     The TDI is only available in a trim level equal to the GL, so these options are not available: split rear seat, sport seats, leather seats, side air bag, trip computer, roof-mounted antenna, driving lights, and a few things like that.  Cruise control is standard, though, while not part of the GL package.
     The front suspension is too soft, as if it were designed for the gas engine and doesn't handle the extra weight well.  The car tends to wallow a bit on uneven pavement.  Also the steering and overall feel is not as direct as with previous VWs, although the tires could be partially at fault.  When we burn these tires up we'll see how it feels on Michelins or Continentals.
     Had too much trouble finding one with the "Comfort Group" which adds power windows and mirrors and alloy wheels.
     Expensive: base price was $15,770 and by the time we got out the door the total was around 20K. This was even with the car going out at $100 over invoice!  That's a lot for a basic VW sedan.  But the used ones were expensive enough that a new one made sense (especially with the service).  Also, there were no used TDI models, since the engine was new for '98 in the Jetta line.
     Some of the dealers were using the wrong motor oil during routine services.

VW Diesel Links and Modifications

Fred's TDI page - http://www.tdiclub.com - great TDI info, message forum, archives, etc.
     Poor man's chip - the Evry resistor modification - original thread - follow-up thread
     .205 injector upgrade
     Trick the coolant glow plugs into running (heat the car faster)
Remote windows for VWs, plus New Beetle info - www.alientech.net
Diesel Westy page - http://www.cs.rochester.edu/u/jag/vw/
Scott Farrell's TDI page - StealthTDI.com
VW manuals, in PDF form, for purchase - http://erwin.volkswagen.de
Ross-Tech, maker of VAG-COM diagnostic equipment for newer VWs - http://www.ross-tech.com

VAG-COM procedure links

Recoding and adapting locks on Jetta and Golf (most cars from '98-on).
TDI Engine setup (different TDI but similar) http://www.haywood-sullivan.com/vanagon/TDI/tdi_diagnostics_en.pdf
Recoding locks on Audi A4, A6, A8, TT-coupe, TT-roadster, S4
TDI engine ECU adaptations (thread on www.tdiclub.com) to avoid engine shuddering on A4 TDIs.
Adjusting EGR duty cycle: Select engine control module, select "login", enter 12233 as the no-longer secret code, select "adaptation", go to adaptation block 3. It should display the requested and actual air going into the engine, probably around 250 mg/stroke (otherwise, you are on the wrong screen). Enter 33768 in place of the default 32768, click "test". Note that the displayed amount of intake air changes to around 370 mg/stroke. Then "save".  This should reduce the duy cycle to 4%.

If you have any other recoding information, please send them to me or to


Rear wheel bearings
    Inner - SKF BT1E 328688AC/Q (OEM)
              Federal Mogul A-15 (Bower L45410 outer race L45499 inner race)
    Outer - SKF LM11710/Q (OEM)
               Federal Mogul A-1 (Bower LM11710 outer race, LM11749 inner race)
Oil Filter - Purolator equivalent

VW Diesel Mailing Lists

VW-Diesel: http://www.audifans.com/mailman/listinfo/vwdiesel

VW-TDI group: http://autos.groups.yahoo.com/group/VW-TDI/

Jetta Jetta


I was asked:

1) did u buy it new?
2) have u had any major problems with it?
3) how much mileage do you get out of it?

Bought it new, now have 140k miles on it.  Usually get low 40s for economy; best ever was 51 and worst ever without a trailer was 39 I think.  With a trailer it can go down to 30 if I'm moving quickly (80mph, etc).

I've had one major problem (specific to this model) and a few minor things.

Major: occasional loss of turbo boost.  The computer detects an out-of-spec level of boost and shuts the turbo down.  There is a very good procedure online that I will use to diagnose this; I suspect it's an oil leak in the wastegate which might require replacement of the turbo.  But you know, after 140k miles and nearly four years without car payments, it's OK if I spend some money on the car.

Minor: trim strip fell off passenger door, glove box latch is broken, and the headlight switch went bad.  All are known weaknesses of this model, and aren't unlike those of any car model.  I would wholeheartedly recommend this car to anyone.  I paid more than I needed to for it, and have never regretted it for a moment.

If I had the electric windows, I'd probably have had problems with them also.  They were very problematic on the A3 body. More info than you ever need is on the site www.tdiclub.com

We've had a number of older diesel VWs. A Rabbit that went 294k miles with basically no problems at all (engine was never touched, except maybe valve adjustment). An '85 TD Jetta that is over 300k miles; crappy alternator drive system but that's about all. My neighbor has a new TDI Jetta wagon and it's VERY nice.