Glow Plugs Is it easy to change the glow plugs in my 2002 jetta tdi. If so, how do I do it and where are the glow plugs located.

all 1.9 tdi engines with 8v cylinder heads have glow plugs out side cylinder head, you will find them easy. Torque is from 12 - 14 Nm.

Hi.

The glow plugs are plugged into the cylinders. They basically do the same that spark plugs do in gasoline/petrol fueled engines.

It is quite rare that glow plugs heater circuits go bad all at once. Test also the wiring harness.

Here a forum that can help you a lot. Picture below is from the tdiclub.com forum in this link:

In addition to the 4 primary glow plugs, the cooling system also has 3 Coolant Glow Plugs to help provide extra heat to the cooling system in order to warm-up the vehicle's interior more quickly, and enhance overall engine warm-up time. (Example - Some Mercedes diesel engines use electrical heaters in the cabin because their engine is so thermally efficient.)
Likewise, this auxiliary source of heat from the 3 Coolant Glow Plugs is necessary because of the VW 1.9 TDI engines outstanding efficiency, which wastes very little heat.

The 3 Auxiliary Coolant Glow Plugs are located at the end of the aluminum cylinder head (in a protruding flange) directly below the vacuum (brake booster) pump, which also connects to a coolant hose.


The 3 Auxiliary Coolant Glow Plugs use two (underhood) relays which are monitored and controlled by the ECU. During a cold start, the vehicle's interior temperature selector switch helps the ECU choose one of three modes depending on the amount of heat required to warm-up the coolant.

For example, Coolant Glow Plug #1 can be selected to operate all by itself, or #2 and #3 can operate together as a two-some, or lastly, all three glow plugs can form a triple source of heat for maximum enhancement of engine warm-up time.

After the engine is completely warmed up and the thermostat is open, the Coolant Glow Plugs normally shut-off and remain off unless the (thermally efficent) engine cools down sufficiently to have the computer signal them to come back on to keep the engine and cabin air warm. Extensive idling times at stop lights or in the driveway are scenarios where these glow plugs are most likely to recycle on and off.

In conclusion, the period of Preglow and Afterglow is determined by the engine's coolant temperature (during a cold or hot start), which helps the ECU select a predetermined time-cycle for the combustion chamber and / or Auxiliary Coolant Glow Plugs to follow.

Finally, one myth that needs to be immediately debunked, is the belief that the TDI's advanced Glow Plug System is linked to the opening of the driver's side door, which is false! It is also noteworthy to mention that some earlier VW diesel glow plug systems were operated in this manner, but not so with the advanced VW Jetta 1.9 TDI engine.

on that car, they had lots of problems with glow plugs and the wiring to the plugs, i would change them every 50,000 miles, there not expensive or hard to change,

yes glow plugs have a lot to do with engine having tough
time in cold weather. before replacing glow plugs
check relay and fuses.

this is a common problem for these cars glow plugs go bad like spark plugs however the smoke would lead to bad mass airflow meter. it is not telling ecu corrcet miss. disconnect mass airflow meter. when cold see if this makes it start better. it should would means you need new m.a.f. glow plug issue take a test light place clamp on positive of battery then pull off glow plug connectors place tip of test light on glow plug the bad one will have a dull light unlike the good one which will be brighter. will need new plugs and wire harness four **** connectors and wire striper and crimper will fix concern good luck

They are absolutely pulling your leg if they're telling you that you have 7 glow plugs. It sounds like they don't have a clue about TDI's.
Everything you ever wanted or needed to know about TDI's can be found at www.tdiclub.com You should even be able to find a knowledgeable guy in your area that would be willing to take a look at your car. These guys know their stuff. Better than any VW dealer on the planet.
Read this thread - you might be able to figure something out on your own: http://forums.tdiclub.com/showthread.php?p=749854

Are you having problems with your heating/cooling? OR did you get a check engine light and found out about P0380 when you brought it to the shop?
You more than likely have an issue with your glow plug harness. The connectors on the glow plug harness (where they plug into your glow plugs) prob need to be cleaned. Read this thread too:

http://forums.tdiclub.com/showthread.php?t=188770&highlight=p0380

very common for the harness that plugs onto the glow plugs to have too much resistance it will still work but will set codes

well will it start using a little shot of starting fluid ? if so you might have a weak pump . try this and see . thanks Jerry

http://forums.tdiclub.com/showthread.php?t=79819&highlight=tdi+glow+plugs

Lots of info including a tutorial. Doesn't seem to be that difficult.