Golf 3 1.9 TDI: Glow Plugs Not Working?

Vehicle: Volkswagen Golf 3, 1.9 TDI, 75 hp.

PROBLEM: It no longer ignites properly, which makes it start very poorly.

INFO: Spark plugs were replaced 1 year ago.
- The indicator light for the heating function shows that everything is normal, as if it were working.
- According to the glow control system, there is no voltage applied to the glow plugs during the preheating process.
- The fuse for the glow plug system in the engine compartment has not blown.
- The other fuses in the car are also all okay.



Please, please help me, I have no idea what could be causing this.

'Possibly the control unit, which shows no visible damage from the inside or outside, but is very expensive. It could also be the glow plug relay, but I haven't been able to identify it. When it was working, you could hear a relay clicking when the glow plug indicator light went out, but that sound is no longer present.'

Even a 1.9 TD (AAZ ???) should start well in these temperatures without glow plugs. Don't focus solely on the glow plug system when troubleshooting... Search the forum for starting problems. It could be caused by many different things.

"Something's not right with my AAZ engine... Is this the crankshaft bolt for the timing belt pulley?"

Do we really want to be like that ?

http://home.arcor.de/sgrafen/salatoel/kw_schraube/kw_schraube.html

Even a 1.9 TD (AAZ ???) should start well without preheating in these temperatures. Don't focus solely on the glow plug system when troubleshooting... Search for 'starting problems' in this forum. It could be caused by many different things...

It's currently 8°C (46°F) at our place in the early morning.

The three-chamber diesel engines in the yard don't make a sound other than white smoke without preheating.
(The TDI faction always does that.)

'The only thing to do is to check the heating system. Check the temperature sensors, etc. If necessary, trace the wiring to find the relay... Unfortunately, I don't have any G3 schematics available.'

CU Gremlin.

It's currently 8°C (46°F) at our place in the early morning.


Sorry, I was still expecting summer (Yes, we're still having summer).

Hi,

Are you sure the fuse is okay? Sometimes they can have a hairline crack right next to one of the screws, which you can't see.
If you haven't already, be sure to remove it.

Greetings.
dieter

Okay, I'll remove the fuse again and take a look at it! But as I said, I no longer hear the relay clicking once the preheating indicator light goes out. According to VW, it's the control unit, which costs 170€. But I've looked inside that part, and I can't see anything wrong.


Where can I find plans for my slingshot, or does anyone else have something like that?

Even if you can't see anything obvious, a defect shouldn't be ruled out, right?

Find the relay, check if there's voltage reaching it. If the relay doesn't engage, either the relay itself or a fuse protecting it is faulty. If it does engage, the strip fuse is likely defective. If no voltage reaches the relay, then the suspicion that there's a problem with the VW's electrical system is probably correct. Check all of this first, before we start making wild guesses!

Thank you very much, I will check everything tomorrow! I will write to you tomorrow with my new findings .

VW is replacing control units with great enthusiasm (little work, lots of money...). As joergs says, it's best to measure the system to narrow down the source of the problem.

@Shelby:
Please also check your emails.

I just finished reading that! Great description! I only have one more question: which relay is used by the engine control unit for the glow plug system? There are so many .

I only know which one is the flasher relay!

Many thanks again for the documents!

It should be located at relay position 12 (number 102, 103, 104, or 142).

I did some measuring and eventually replaced relay 104 in slot 12, and now the car is working completely again, so it's running smoothly like a clock.


Thank you very much for your help, which was very beneficial! Thank you, thank you.




ps: The relay cost me 20€; at VW, they wanted to sell me a new control unit, which would cost around 180€.

I guess I got away with it again this time .

I had the same problem, but the cause was different.

'When it was cold, my Golf 3 TDI (90 hp, manufactured in 1994) started very poorly.'
(The starter motor kept turning and turning). After a few seconds (sometimes longer),...
Occasionally, a puff of smoke would come out of the exhaust, and then the engine would sputter for a while.
It wasn't running smoothly at all for the first few seconds, but then it started working normally.

I then had all the glow plugs replaced at the workshop, which cost...
This was supposed to be the standard solution for this problem, but it was useless.
Whether the engine was warm or the outside temperature was warm, it started without any problems.
After some measurements, I discovered that the glow plugs had a connector attached to them.
No voltage was detected during the preheating process.

Solution at my place:
In the fuse box located under the steering wheel, you can see all sorts of things.
The fuse you're looking for is a 50A fuse located in the upper right corner, behind the relay labeled '21'.
hidden (you can actually only see it if you look at the fuse box from a certain angle).
Befestigung löst und ein bisschen dreht). This one was broken.
The whole thing had also quite confused me, because there was something in the engine compartment, below the...
In the middle of both windshield wipers, which is also where the glow plug control unit is located.
another backup is in place.