glow plugs 98 jetta

[dej]

glow plugs 98 jetta

in anticipation of having to fix these in the next few days, could someone please tell me where the glow plugs are located on my 1998 jetta tdi - i wanted to check the resistance of each one b/c my check engine light is coming on after 30 seconds of driving - i brought it to the dealer a couple of weeks ago for the same problem, they said i needed the battery changed - i had this done but a week later the light came back on - i'm taking it back to the dealership to have code checked but i would rather check and possibly fix the glow plugs myself to try and save some money

 

[dzcad90]

Re: glow plugs 98 jetta

The glow plugs are located in the cylinder head, under the injection lines. a 10MM Deepwell and an extension is required to change them. If you are patient, you do not have to remove the injection lines.

Be sure to replace all 4 glow plugs at once. Also be sure to test the glow plug harness, as these go bad somewhat frequently and will cause the ECU to say that the glow plugs are bad.

Unplug the coolant temperature sensor (The one closest to the head) to have the computer give the longest possible glow for testing purposes. Note that this this will cause a Check Engine Light.

 

[WillR]

Re: glow plugs 98 jetta

I'm going through this as well. I replaced the glow plugs, 2 or 4 were bad. Plus I had a real long glow plug light, plus the check engine light after 20 sec.

I replaced the coolent sensor. It also fixed the dash gauge that started reading 160 deg all the time.

Problem is I got the "green stripe" sensor instead of the orginal Yellow stripe one. This caused the glow plug light to only stay on 1 sec (its in the 30's deg F.) and no glow plug action. Its real rough cold. So I got the correct sensor and installed it tonight. Tomorrow I will see if the glow plug action is back, but I still got the check engine light.

One thing I noticed is the engine runs much better with the new coolent sensor. I guess this sensor also tells the ECM what the coolent temp is to adjust timing, I mean it really runs 100X better then it did before the sensor.

Any chance this CEL needs to have the code cleared before it will go away?