How To Repair and Maintain
  2003 Volkswagen Jetta 1.9L TDI Wagon

© 2019 Brian Mork

Introduction

Testimonies

Early LIfe - 2005-2009

June 2014 - 5-1/2 years of storage

June 2014 - add a trailer hitch

Parts received in the box.  I ordered the electrical adapter in the plastic box separately.  The parts are laid out showing where they go during installation.	I used the car jack to hold the hitch into position for a trial fit.  Right side is held in the tow loop using the plate and bolt provided in the kit.	The hitch and bolt plate did not fit flat against the tow loop because a blob of body sealant was in the way.  I used an X-acto knife to cut away the body sealant (shown as the white piece in photo).	The rearward plastic storage bin behind the spare tire needs to be temporarily removed to access the metal floor for drilling.  Use screwdrivers under each side to not break the plastic retainers when you pull them up.	This picture looks under the car from the left side. Hitch needs to fit tight UP and RIGHT against  the body because bolts will be put in both ways. Adjust fore and aft to get the hitch coming straight out the back.
This picture shows the back left hole and the plate that will be installed over it.  I drilled the holes with a smaller drill and then drilled them out to the final diameter.  I used an even larger drill to de-bur the final hole top & bottom.  As you drill each hole, put a bolt in it to hold the parts in exact position so the next hole will be drilled in the right place.	This picture shows the left side bolts and interior mounting plate temporary installed. After drilling holes, install the pieces at least finger tight to make sure everything fits. I had to adjust one hole with a round file about 1/32". The back bolt is seen mirror imaged in the stainless steel molding over the tailgate.  I had to use a metal grinder and remove maybe 1/4" of stainless to clear the plate and the bolt head.	Left side bolts in final installation - with black tar water proofing and rust proofing.  Temporary installation was removed and each bolt/nut was coated with black tar and re-installed. After all five bolts were installed (3 left, 2 right), all were torqued to specification.	The right side has only one new bolt hole required. In addition to the visible plate and nut on bottom, there is a spacer plate wedged between body frame panels.  I used a long flat-blade screw driver to gently tap it into place from underneath and behind the car.  Get the hole alignment right on the first time because there is no way to remove the spacer once jammed into place. I would advise peeking in the trunk, and when you see the bolt hole starting to line up, put a screwdriver in the hole and start to wiggle it in alignment as you put the last few hammer taps into place.	{picture pending} Shows the bottom side after final installation, including hardware 100% covered in black tar water proofing.
This shows the wiring harness disconnected from from the rear left tail light, and before I spliced into the wires.	This picture looks backwards and left into the rear tai light area.  I used a socket set to remove the nut from the bolt stud that provides a grounding point.	Wires from the electric adapater that connect on the left side, and the cone nut that came off the grounding stud by the back left tail light. The white ground wire came with a connector installed.	The left rear ground bolt after the nut was removed.  The white ground wire was slid onto the same stud and the nut was replaced.	Left side wire installation for left running light, turn light and brake light.  Notice how the wire lengths and wire splices were staggered so the splices don't bump into each other. The white wire goes behind the panel to the grounding bolt.
Driver side re-wrapped after splicing.  Notice how the staggered splices fit to make a tight wire bundle instead of a bulge.	Back stainless steel tailgate removed to route the green right turn wire underneath it to the right side of the car.	Passenger side wiring rewrapped after splicing in the green wire.  I needed to use a coat hangar wire with hook on the end to wiggle the long green wire (right turn signal) from the tail gate area into the right tail light area - it's a tight fit due to body panel pieces.		The folks at etrailer.com were phenomenal.  I could not read the b&w low contrast copy of a color instruction sheet.  They said my brand of hitch was actually made by Reese and they found another instruction sheet and emailed a copy.  I advised it had different fittings than mine and a day later I received this hand-noted high contrast instruction sheet for my hitch (click on the image to get a pdf copy).  Perfect!  Yea for etrailer.com!

July 2014 - steady as she goes

September 2014 - new battery

March 2015 - new timing belt, water pump, idler pulleys, timing  belt.

September 2015 - clutch disintegrated.

November 2015 - new fuel filter really helped!

May 2016 - alternator pully blew up

August 2016 - brake light switch replaced

January 2017 - rebuild the window regulator (up/down mechanism)

January 2017 - coolant temperature sensor

First step is to drain some coolant out of the engine block so that it doesn't come flowing out the sensor hole while I'm switching sensors.  It's easy to drain coolant fluid from in front of the driver side front wheel.  The red arrow shows the knob that opens the drain.  It's not like a twist open faucet.  Instead it does about 1/4 turn out of a detent, and then the entire knob slides out about 1/4" and the fluid starts flowing. Size of the tubing was ...uh.. forgot.	Collecting almost all the coolant in a clean catch basin.  Actually, all the sediment and flakes sink to the bottom and I decant off the clean liquid back into the car. Works great.	Turns out the radiator drain was not the low spot for the engine block, which I needed to drain so fluid would not flow out of the pressure switch hole while I was switching sensors.  This is a photo looking down toward the ground from the front of the car.  Notice I pulled one of the coolant lines from the engine coolant housing.  The green arrows show the connection I pulled apart.  It came apart pretty eaily once the clamp was slid back.
The coolant sensor on the back of the engine driver side is a little bit hard to get at.  Depending on how your coolant sensor is rotated in the hole, the release for the electric plug could be hard to release.  This photo shows how to put a screw driver blade into the connector from the wire side toward the sensor.  Once in the slot, leverage the handle toward the wires leaving the sensor.  Simultaneously tug on the plug and it will come out.  The area is really tight so I actually used a short 3" stub of a screwdriver tip I had laying around - there wasn't enough room to get an entire screwdriver in place. Also note if your car has a 2-WIRE or 4-WIRE sensor because the parts store will ask you.	After pulling the electrical plug, pull the plastic "C-clip" downward until it disengages.  I used a screwdriver for the first 1/4" and then just pulled it downward with my fingers.  After the clip is removed, pull out the old sensor, and make sure you get the O-ring, too.  I had to reach in the hole and pull out the O-ring.   When putting in the new sensor, lubricate the new O-ring.  I found it easier to put the O-ring all the way in the hole and then insert the sensor.  Rotate the sensor so the connector disconnect is in a convenient location.   This photo shows the new sensor just short of being clicked into place, looking from standing next to the driver side fender.  One side of the C-clip is visible to the left in the photo.  I rotated the sensor so that the little catch and the screwdriver release are toward the driver fender side of the car.	To refill the coolant, I initially pulled the most convenient line - top front and center.  It took fluid very slow, so I reconnected the two ends highlighted with the red arrow in the photo and pulled off the ~other~ end of the same tube.  This allowed me to add coolant faster.  When I added about 1/2 the coolant, it started to overflow out the open hole on the back behind the engine (sensor was not in place yet).  I stopped adding coolant and mounted the new sensor.

February 2017 - alternator (again) - brushes

You'll need to remove 4 shrouds - the engine under belly shroud, the battery cover, the cover on the top of the engine, and the right fender belly shroud.  The side one has one slide on support in the front, and two friction nuts holding the plastic to the metal frame.  I found the friction bolts came off easily by using a small size construction pry bar and using the 90 degree bent end, I tilted (not pried) the nuts loose.  I don't have a picture of the fourth shroud because it was off in the house getting an unrelated structural repair (see down later in the web page).	Disconnect the alternator output line from the hot battery bus.  I don't have schematics, so I ~think~ I got the right wire by following from the alternator.  If you do not do this, and you allow the other end to short against any metal engine parts (going to happen), you are going to get an up-to-110-amp spark (size of the fuse link) because this will short your battery to ground.  Disconnect the wire!	First I easily rotated the serpentine belt tensioner and slide the belt off the A/C pulley.  Then, remove the engine turbine air cooler pipe.  The connections are incorrectly labeled "Turbine Air Inlet" in the photo.  Instead, this tubing is part of the cooling loop that takes hot compressed air and cools it before returning to the engine intake manifold.  One end has a typical hose clamp and the other end has a wire clip that is easy to pull loose with a flat blad screwdriver. The A/C compressor comes off next.  Once you pull the bolts, you'll need to gently pry the compressor out of position because it has friction bushings on each support bolt.  I found the freon lines were long enough to just let the compressor dangle on the ground.
Unbolt the alternator like the A/C compressor.  Again, pry it loose.  This will be harder because space is limited.  I went back and forth from the top and bottom and left and right sides and it eventually came loose. Use a torx bit to remove the passenger side radiator fan and move it out of the way.  Then you can wiggle the alternator out the bottom of the engine compartment.  First time I did the whole process, I had 4 hours invested.  Next time, when I know ahead of time what tools to use and how to do it, I predict about 1.5-2 hours.	After getting the alternator out, I could tell it had a bad bearing by pushing on the pully and spinning the pulley.  Strangely, I think it was the back side bearings (by the brushes).  Since this alternator had a lifetime warrantee from only 9 months ago, I was able to get a free replacement.  Actually, I looked at buying a $190-$200 new Bosh alternator thinking, "I'd rather not do the work to replace another one even if it is free." I hope I made the right choice.   The A/C compressor bushings slide a little bit open easily with a C-clamp and a socket that fit over the bushing.  The remanufactured alternator going into the car (warrantee after the first one failed after 9 months), had bushings that had been bead blasted into position. They did not budge with the C-clamp.  I ended up using the mounting bolts (which were threaded all the way to the top), a socket, and washers as shown in the photo.  I tighted the bolt and pulled the bushings through the hole - about 20-25 ft lbs of torque was required, which is more than the working torque for the 8.8 grade bolts, but I think I was well short of the torque necessary to stretch or break the bolts.	Everything went back into the car in reverse order.  Be careful to get the belt routed about right so you don't squish it with the belt tensioner.  Getting all the parts back took a about 1.5 hours the first time I did it.  Watch the torque specs on the bolts.  I looked up 8 mm and 10 mm bolt torques for 8.8 grade bolts.  The alternator and the belt tensioner require about 17-20 ft lbs and the A/C bolts use about 30 ft lbs.  I would be interested to hear from anybody with a service manual that gives the VW recommended torques.  I just used the generic bolt size torques. The belt tensioner was easy to hold in position from underneath the car as I slid the belt around the A/C pulley. After installing everything, I started the car and all appeared to work.  Initially I left the alternator wire loose at the bus bar to see if I could measure DC or AC voltage directly from the alternator.  Nothing.  The car must be too smart and leave the alternator clutch disengaged if it doesn't sense the voltage.  Oh well.  I turned off the car,  connected the wire, and re-started the car.  Nice 14.2 volts, rather than the slowly dying 12 volts of the battery that I had before.
Serpentine belt routing for reference.

  Here are the tools I used to replace the alternator.  It would help a lot to pre-position these.  From left to right...

• Pliers removed the turbine coolant line clamp.
• The C-clamp and washers were used to slide the A/C compressor bushings.  The mount bolt was used to slide the alternator bushings.
  
• The 16 mm closed end box wrench was used to rotate the belt tensioner from beneath the car.
• The 3/8" breaker bar was used to loosen the 3 tensioner bolts - I could not get a powerful angle with a socket wrench because of the car frame, power steering tubes, and wire bundles.
• Sockets were used for various things -- all metric.  The deep sockets were good for the A/C compressor or the alternator (can't remember which) when the frame was too close to use a 3" socket extendor and a normal socket.
• The torque wrench was used to do final cinching down of the bolts
• The stubby 3/8" socket drive was great for pulling out and installing the belt tensioner bolts.  $12 for 3 sizes from Harbor Freight.
• The red & black 1/4" drive was used with torque bits to pull the belly pan and the radiator fan.
• The articulated 3/8" drive was used to tighten the tensioner bolts that fit very tightly behind the power steering pump pulley.
• I used two different size torx bits from the yellow kit - one for the belly pan and one for the radiator fan.

February 2017 - repair the engine right fender belly

I drilled two holes on the left and right side of the hole so that the little flange piece with the bolt hole would exactly stay in position with a wire brace (the plastic flange piece is slipped out of position in this photo).  I positioned everything in place and put a layer of JB Weld around the hole and surrounding the wire.  It has a good history of sticking to plastic things and flexes just a little bit to make it not crack loose.

With the JB Weld base cured around the edges, I then covered the hole from the bottom with duct tape and filled the void in with some 6-minute epoxy.  Here's the final result before going back onto the car. Now the little plastic flange with the bolt hole will hold this piece to the frame, so it's strong enough to support the central belly shroud that screws into it.

February 2017 - glow plugs

  

These plugs were electrically confirmed bad in the engine block and once removed.  In the engine, the plugs were 3.5 ohm, 3.2 ohm, 600 kilo-ohm, and 100 ohm.  To check the meter leads, I also check the resistance right back to the engine block, which showed a residual resistance of 3.4 ohms.  Well.. that would mean one was negative resistance which is silly, but suffice it to say two were clearly good and two were clearly bad. In the photo you can see #3 is nearly full open circuit at 630 kilo-ohms.  Basically the filament is busted.

Glow plug #4 is about 90 ohms, still WAY more than the specified single digit ohms, and I'm surprised the ODB computer didn't complain about it.  Plug #3 was doing nothing and #4 was basically a little bit warm but not much.  No wonder my engine was starting harder and harder with puffs of stuff out the tailpipe.

May 2017 - glow plugs round 2

The check engine light came on.  Taking it to the fix-it store revealed that glow plug circuits 3 and 4 were giving trouble.  I had already lived through this once already and knew that the car would drive okay with the error code.  So I waited a few weeks until I had time.  

I purchased 2 more glow plugs - probably should have done this the first time around, but at $23 each I was hoping I didn't need four.  Interesting, the resistance measurements were too low this time instead of too high.   It took me only 1/2 hour to pull the engine cover, pull the two plugs and put two new ones in.  It took about 12-13 ft lbs to break them loose and they came out firmly but steadily.  Neither was very difficult like last time.

I used some high temperature thread lubricant and screwed the new ones in place and tightened them to 11 ft lbs.  The #2 plug (counting left to right as you look into the engine compartment) needed an articulated knuckle for the socket to get around the fuel injection lines.

Here's a picture of the tools I used.  Actually the entire socket set is misleading.  I used only the 10mm to take off the engine lid.  I grabbed a 10mm 6-point deep well from another kit to grab the glow plugs.  I would really recommend NOT using a 12-point socket because they are pretty tight to turn out, and there is no way to grab the sideways if you strip the flat sides.



LIke last time, the two this time had carbon deposits making them look black on the end.  Here's a picture.  If you look close, you can see the threads are pretty clean on these two unlike one of the previous ones.

June 2017 - glow plugs round 3

January 2018 - Clutch Master Cylinder

November 2018 - Sunroof Drains

January 2019 - Tighten window clips (again 2 years later)

• Wedge out the door handle clip away from the interior car toward the outside of the door
• Wedge up the switch assy from the door, releasing 3 clips across the interior side and 3 along the exterior side; unplug elec connector
• Remove 3 torque screws across bottom of door
• Remove 1 phillips screw front top of door (by speaker)
• Remove 3 large phillips screws from center area of door card (top side of the arm rest)
• Wedge loose 3 plastic button clips along back of door and 3 along front of door panel
• Door card panel wiggles upward and off the door lock knob and out of the plastic trough along the window
• Hold the door panel while disconnecting interior electrical connectors on the back side of the door card
  

• Pop open two plastic round rubber covers from inspection holes.
• Lower the window while pressing the window down to stay in the clips.  Go down until the torque screws are visible in the inspection windows.
• Tight both torque screws to at least 65 in lbs. I held the window up while trying to motor it down to make sure the motor stalled before the clips let loose.

February 2019 - Coolant sensor again 2 years later

November 2019 - Alternator again (3rd and 4th time)

December 2019 - Goodbye to an Old Friend

I drove the car home, and started to wonder about replacing it.  Turns out I did buy a 2-year old vehicle to replace it and put the Jetta up for sale. As I looked forward to where life was going, now was the time to reset with a newer car rather than wait five years.  Five years would have put another 60,000 miles on the car, pushing it to 243,000 miles, and that's probably a little long for me (although the Subaru I had went this far).

When I advertised it on Craigslist,  I was inundated with responses.  It appears the 2003 (last year of the ALH engine) has become somewhat of a collector's edition.  Someone drove in from out-of-state and looked it over really well.  It was in excellent condition except he said it was developing no power.  I guess I had gotten used to it like a frog in warm water eventually getting cooked. Nonetheless, he thought that would be pretty simply to currect.  He was right in both respects.

 

The day after closing the sale, he sent some pictures of the intake manifold downstream of the EGR valve.   Ugh.. nearly totally plugged, without any DTC complaint from the computer.  The entire engine was breathing through that tiny hole!  He replaced the manifold with one he had from a project car and he said that "woke it right up!"  Lesson learned:  if you have a TDI engine and you're in that 170,000 mile range, do the preventative maintenance of cleaning out your intake manifold.  It is well worth it!

Additional Resources

• DIY - Replacing the Front Door Window Regulator Clips and/or Door Lock Module on vwvortex.com
• Window Regulator Removal and Repair for MK4 Volkswagens on myturbodiesel.com
• Door Card (panel) Removal on a MK4 Jetta or Volkswagen Golf on myturbodiesel.com
• Reset the "check engine light" on fixya.com