Doka td-air intake

Post by **Chilla** » 10 Feb 2008, 21:22

Trying to id an air intake component thats fitted in the o/s of the engine bay (in the air intake area). Its black, plastic, has a plug in connection and relay nearby.
The unit was unplugged when I bought the vehicle and the rubber hose from the unit disconnected.
The only thing like it that I've found on www.vagcat.com is the cyclone unit fitted to the 1.9dg engine. Nothings listed for the td air intake setup.
Was a similar unit fitted to the 1.6td air intake set up?
Any ideas?

Post by **dave friday** » 10 Feb 2008, 22:49

Possibly the turbo cooler? my van has one [ fitted on the near side of the engine bay] the air hose was missing on mine!. have another look on "vagcat" under Diesil engine.

Post by **airhead** » 11 Feb 2008, 00:02

Yeah it sounds like the turbo cooling fan. It switches on with your auxiliary water pump and blows cold air over the turbo when its getting hot and bothered.

Post by **Chilla** » 11 Feb 2008, 11:35

Doh ! yes guys it is the near side rather than the o/s

tried again on vagcat but cant find the unit
Anyone point me to an illustration of the setup and how it all plugs in.
thanks

Post by **syncroandy** » 11 Feb 2008, 13:23

It's in the electrical section of ETKA, illustration 148-50. I've placed a PDF on my webspace:

Link

I can also scan in the wiring diagram should you need it.

Post by **Chilla** » 12 Feb 2008, 08:31

Perfik Andy so its a turbo cooler. As with others mine wasn't connected to anything and the pipe detailed in the diagram is missing I think the aux waterpump is also disconnected.
cheers for the replies

Post by **HarryMann** » 12 Feb 2008, 12:06

If it comes on at all, its when the engine's hot yet turned off, or idling to prevent oil cooking in the turbo galleries .... so i was told

The aux. water pump work at times like these too

Post by **Chilla** » 12 Feb 2008, 16:17

Thanks HM
Syncroandy- any chance of posting that wiring diagram interesting to see where the turbo cooler takes its power from as harrymann says the unit is ....supposed.... to come on when the engine is at idle or stopped.
So where does it get its power feed from ? Im guessing that there is a thermostat involved somewhere!
thanks in advance

Post by **syncroandy** » 12 Feb 2008, 19:00

It takes its power via a 10A fuse from un-switched 12V (terminal 30) in the engine-compartment junction-box. Along with the coolant circulation pump, it's switched by a thermo-switch in the water manifold on the flywheel end of the cylinder head. The PDF's are here:

Coolant Pump
Turbo Cooling

Post by **Chilla** » 12 Feb 2008, 21:02

Nice one Andy !
cheers

Post by **Syncro G** » 14 Feb 2008, 18:12

Anyone know how to identify the sensor for the aux pump/turbo cooler?

I've decided mines definately not right as its on all the time the engine is remotely warm and runs on for up to an hour after hot switch off.

The heaterplugs nearly always run for the full 12 seconds, but very rarely don't come on at all - hasn't happened for a while, I suspect it was a hot day in the summer when the engine hadn't been stopped for long. They've never not worked when needed, they just also work when they blatently aren't needed.

Having recently debated this with CJ we wondered if the the sensors were simply on the wrong plugs so things happen at the wrong temp? Ie the aux pump is on whenever the heaterplugs aren't needed (engine near running temp) and the heaterplugs don't work when the engines superhot (when aux pump should be on).

The wireing diagram seems to surgest the heaterplug thing is a sender rather than a switch, so should it vairy the preheat time between 0-12sec or just make them work all or nothing. If its a sender how does it compair to the water temp sender? I think any could easilly be fitted in any of the 3 places and I've yet to find any decent info these sensors.

Post by **syncroandy** » 14 Feb 2008, 18:56

Syncro G wrote:Anyone know how to identify the sensor for the aux pump/turbo cooler?

On the diagrams I posted it's identified as F95, ' Thermoswitch', 107 degrees C. Physically it's a two pin sender mounted in the plastic water housing on the front of the head. I assume it's open-circuit until the temperature is reached.

There are two other senders G27 for the glow-plugs, and G2 for the temperature guage, these are both mounted in the water housing on the side of the head.

These can be mis-connected, the plugs will fit the wrong sender, eg. the glow-plug sender plug will fit on the thermo-switch.

(My experience is with the later style engine with plastic water housings, the early style had metal housings and single-pole senders.)

Post by **Syncro G** » 14 Feb 2008, 19:18

I can't remember which wire goes to which but I think on mine the aux pump switch [wireing] goes to the houseing behind the injectorpump. Think its the coolent temp sender wireing on the one at the front of the head but aren't too sure. The coolent temp seems to work fine so whichever that is I think that one atleast is matched properly.

Are the heaterplug and coolent senders the same or different? Any distingwishing features between these senders/switches to identify them? As far as I'm conserned they are all 2 pin plastic things that aren't garanteed to be in a certain position, and the plugs are interchangerble. Obveously the plugs are easily identified by the wireing colours. Its one of those things I wired up as it was before I swapped the heat september, but that doesn't mean whoever last worked on the engine wired it up right - someone broke one of the locks on the plug for a start, though it still stays there (maybe it would only fit on one of the sensors if it wasn't broken?). The houseing needs changing anyway as the plastic is cracked and leaks very slightly.

Post by **HarryMann** » 14 Feb 2008, 19:48

The housing needs changing anyway as the plastic is cracked and leaks very slightly.

This is a wekaness on the diesels and can stop you in your tracks if not careful... losing water, overheating, check this first and don't continue until its sorted.

Post by **andysimpson** » 14 Feb 2008, 20:08

HarryMann wrote:
The housing needs changing anyway as the plastic is cracked and leaks very slightly.

This is a wekaness on the diesels and can stop you in your tracks if not careful... losing water, overheating, check this first and don't continue until its sorted.

This is a major problem on every vw group vehicle for lasr 20 years.