1999 2.4 TDI Synchro, temp sensor and opening front grill

[Scroty]

Hi,
My 99 TDI has been having problems with intermittent lack of power lately. Seems to run normal and then suddenly loses power, especially under load. Sometimes only lasts a few minutes and sometimes a few days. Like the AC is turning on but times 20.

I've been trawling around and reading about the temp sensor so I dropped the engine protector from underneath, found the wiring harness thing coming from the fuel pump and took a resistance reading across pins 4 and 7.
It came out at 700 Ohms when the engine was still warm and then 1124 Ohms when it was cooled right off. These values correspond to temps around 75 degC and 65 degC according to the table here - fuel temperature sensor and injection pump seal replacement | VW TDI forum, Audi, Porsche, and Chevy Cruze diesel forum but those temps seems too high as I would have expected it to be about 25-30 degs.

Does this sound like a feasible cause of my issue?

I took it to a dealer and they changed turbo sensor and solenoid and then changed the timing belts. They probably needed doing at 260,000km, but there was no change to the problem. It has gotten much worse lately.

I would like to change the sensor myself, but the pump is way down the front and access is hard. I have seen some images of the front of the engine bay "dropped open", but cant find anywhere that describes what you need to undo - just a quick reference to the 2 bolts on the intercooler and some others. Can someone please point me to how to do that as I must be googling the wrong terms.

I hope I'm not asking too much on my first post!

Scott.

[jets]

I have seen some images of the front of the engine bay "dropped open", but cant find anywhere that describes what you need to undo - just a quick reference to the 2 bolts on the intercooler and some others. Can someone please point me to how to do that as I must be googling the wrong terms.

This question comes up regularly from new owners of the T4, it needs a write up.
I had a quick look on the T4 forum where I have seen one in the past with pictures but can't find it now.
Quite easy really. From memory, undo the set screws on the IC [10mmAF] that go into the top panel. I generally remove the IC because I am looking for more room when I do other things. I an sure if you can lift up the top panel with the IC flexed up. If you do decide to remove the IC, be careful you don't tear the rubber insulating blocks [10mm AF]. They are something like $35 ea. You will need some hose clamp pliers for the large tubes. I have used very large vicegrip pliers in the past.
If you have AC, there is a screw & clamp in the centre that needs to be released. Remove the two screws,[13mm AF] one at either end & on the top of the top panel. Remove the 3 Philips head screws in the top grill & 2 in the lower grill.
The painted lower panel is released at both ends by carefully placing a hook just under the headlight & pulling at the top & then at the bottom. There are 2 pins in the guards that hold it in place. The panel can be tight to remove if it hasn't been removed for years.

http://www.vwwatercooled.com/forums/f136/trying-service-tdi-injector-pump-99075.html?highlight=#post1077353

Once one end is released the other will be easier to remove. Lift up & forward the top panel together with the radiator & AC condenser being careful with the fragile plastic that is now quite old. Do not try & separate the top panel over the rubbers from the radiator but lift as an assy.
If you have any problems repost here.

[Scroty]

This question comes up regularly from new owners of the T4, it needs a write up.......

Thanks for the reply. I have got hold of a cable so I will check the temp in vag-com first. The car is running better since I pulled the plug apart and degreased the area, so maybe it isn't that sensor.

If I do open the front I will take pics and post.