Mark Giammalvo specializes in driveability diagnostics at his family business, Sam Giammalvo's Auto Sales & Service, Inc. in New Bedford, MA.
Mark, who has been with the business for
over 20 years, is an ASE Master
Technician and Parts Specialist. He also holds the ASE L1 certification,
and has an associates degree in business
(Printed in the Journal of The Alliance of Automotive Service Providers, AASP)
A service customer decided to bring in his daughters 136,000 mile VW Jetta. The customer mentioned several problems. The car was not starting intermittently and the ac was inoperative. Even after numerous starting attempts, we were never able to duplicate the starting problem. We did find the ignition switch sticking at times so it was given the WD-40 vaccine. The ac clutch was cycling rapidly so the Freon was identified and evacuated. Since we found the Jetta had lost 9 oz. of Freon we recharged and dyed the system. As so common with today's ac work, no leak was found. With the system fully recharged, we discovered that the cooling fans did not seem to be working correctly. Correction, not working correctly as "normal operation" would indicate. As typical with Volkswagens, our service database was very sparse on diagnostic information. There was no description of the Jetta's cooling fan strategy for engine temperature or ac operation. The customer was warned of the overheat and ac problem possibilities and we recommend that he see a VW dealer to further diagnose and correct that system.
A week later the Jetta returned on the back of a tow truck The Jetta was still giving the customer "no start" trouble. Fortunately, the car was now hung up in the "no start" mode. After testing for power in various areas, the ignition switch was found to be the cause. During the ignition switch replacement the air bag clock spring fell apart. After a new clock spring and ignition switch the customer was back on the road. Exactly one month later the VW was back again riding the wrecker. Now the customer was upset. The VW had overheated on the highway. The customer found that one of the fan blades had broken off. For those of you that don't know about the wonderful Jetta cooling fan design, this car uses one cooling fan motor to turn two fan blades. The driver's side fan blade is attached to the motor. The passengers' side blade is turned by the driver's side via a skinny fan belt. Guess how you get the fan shroud out? Evacuate the ac system again so you can remove the ac line running above the fans. After a new fan motor, and belt, the Jetta was running again, although not for long. The cooling system level kept dropping and there were no visible leaks. The engine was now difficult to restart hot. A pull of the spark plugs yielded the rest of the story: coolant in the cylinders. The customer was notified and came down to take a look.
The customer authorized the head gasket repairs but was fearful about going to the dealer for the cooling fan diagnosis. A final look by yours truly yielded some interesting information. Although our VW service information was useless for any system strategy, it did show the location of the cooling fan control module. In addition, the customer mentioned that recently the cooling fans had been on all the time, even on a cold start. After wiggling several connectors, I lucked out and found one that turned the fan on and off when moved. It was the rear connector of the cooling fan module. I was in for a surprise when I disconnected it. Coolant ran out of the connector and out the bottom of the fan module. Well, I know one general thing about cooling fan operation. There definitely should not be any liquids in the control module. Now how would coolant get into the fan module? I was wondering if the mounting location of the module had any bearing on this, after all, its mounted right under the cooling bottle. What a great design, sure guarantees future sales of cooling fan modules. A call to a service manager I know at a VW dealer revealed that this to be a common occurrence. When I asked why European engineering would allow placement of an electronic module under the overflow bottle, the manager had a comical reply: "European cars don't overheat" Now that's a funny one! Needless to say, replacing the module resolved the Jetta's fan troubles. I even added some duct tape to protect the new module when the car overheats again. Now the fan had both high and low speed and came on with hot engine temperature and with ac operation.
I just don't know what it is about servicing Volkswagens. They sure can be hair pullers. I know several local service shops that will no longer service them anymore. Even one of our auto wholesalers refuses to take them as trade-ins now. I chuckle as I remember what he said about them with his thick portuguese accent: "Volkwageen...oohhh no, these noo goood, too mucha troubles, I no wanta."
I've seen my share of VW issues in my 20 or so years of auto service. The Jetta window regulator design is really extraordinary. We must have already replaced 50 of those. Now I hear that VW is finally going to send a mailing to owners for that problem. I'll never forget the first Jetta window that fell in on me a few years ago. I was driving a 2000 Jetta VR6 home for the night. When I first got in the car, I put my arm on the center armrest. Suddenly there was a "ping" as the armrest door button and spring took off in the car. The next morning when I got in the car and started the engine I could hear the pounding of the main engine bearings at start up. Then, when powering down the drivers side window, I heard the window motor run but the window didn't open. After a brief moment, the window crashed down into the door. Lastly, was the teenager that purchased a VW Golf from us. I remember when the kid's father came to pick up the car for him. The father told me that his son was going to college and was studying to be an engineer. I thought to myself: "He's going to need to be an engineer if he ever wants to work on this thing." I will admit though, the Jettas sure do ride nice and tight and the VR6 really does have a lot of power. They are fun to drive, just a little tricky to work on.