Former VWDieselParts.com Forum

I have an 84 Jetta TD in my 81 pickup truck. Today, after driving this truck for years, the injector pump started making a terrible noise. The noise starts at idle or just above, then goes away as I speed up. There is a reduction in power when the noise is happening then when the noise stops power is normal. I recently replaced the glow plugs but this seems unrelated. However I put some injector cleaner in the fuel, which may have been a huge mistake. I drove it for maybe 50 miles and the noise started. I am guessing I am looking at replacing the pump. I usually use Standyne fuel conditioner since I am aware of the low sulphur problem with these old pumps. Anybody have any ideas?

Are you sure its not belt squeal from the alternator? That causes the same power loss until the sound stops. Does the red battery light come on with the noise? Does it happen when you drive through a puddle? Check alt hinge bolt and belt wear.

I'll check the alternator belt again, but I just put on a new one and the tension seemed good. Maybe the new belt stretched a bit. No red light. The sound seems much louder and different than an alternator belt.

Feel any vibration on the foot peddle?
Checked all the mounting bolts?

So I tightened up the alternator belt, its only a couple of weeks old and it was indeed loose. I hope that's the problem, it seems likely. Then when I went to start it, my glow plug relay ( I have Vince Waldon's (vincewaldon.com) alternative wiring system with a separate relay and four fuses going to the glow plugs) went POP, and the system went dead. So i need to chase this down before I can report results. Unfortunately I am leaving the country on Thanksgiving day until the end of the year so I'll get back to you all in the new year!.

Find a 12 mm or 13 mm wide belt (instead of the oem 10 mm) which is the exact length as yours is and life will improve.