Thread: TD5 Auto Question

From the Owners manual:

1. Temperature gauge
Once the engine coolant has reached its normal
operating temperature, the pointer will rise to a
position within the WHITE segment of the
gauge (the precise position will vary according
to climatic conditions).
If the pointer moves towards the RED segment,
this indicates that the engine coolant is
becoming too hot. Should the pointer move
INTO the RED segment and the RED warning
light within the gauge illuminates, severe
engine damage could occur (under these
circumstances, the air conditioning may switch
off and engine performance may reduce in
order to minimise engine load).
Stop the vehicle as soon as safety permits and
allow the engine to idle for five minutes in order
to cool down - DO NOT SWITCH OFF. Seek
qualified assistance before continuing.

From RAVE:

The ECT sensor is located in the coolant outlet elbow on the top of the engine. It provides the ECM with engine coolant temperature information. The ECM uses this ECT information for the following functions:

• Fuelling calculations.
• Temperature gauge.
• To limit engine operation if coolant temperature is too high.
• Cooling fan operation.
• Glow plug operating time.

Apparently there are a number of strategies employed including switching off cylinders so they only pump air to assist cooling the engine.

The red coolant warning light comes on when coolant temps get to 121°C.

cheers
Paul

Originally Posted by eckolsim

Carjunkieanon,

Be careful, it sounds like your TD5 is getting too hot. You may need to check if you've done your gasket as these symptoms are similar to overheating. When the engine gets too hot the ECU limits the fuel.

Thanks for the advice. Temp needle sits pretty much at the 3o'clock position so (hopefully) not getting too hot, but it is chipped with a DPL chip and I know that can cause the heating issues. No whistling sounds and it's been to DPL reasonably recently. I usually don't push it too hard so will have to cross my fingers....pretty broke at the moment.

Mate just replace the MAF. Seeing lots of posts here about cleaning it but really, it's the best $250 I've spent on mine. Better power, better economy (10% over 2500k's including a 700km low range bit). My only beef is that I didn't do it earlier

Like most things it will only make a difference if the MAF is shagged. There is a simple check you can do with a multimeter that while give a very good idea of whether its within spec.

Replacing bits without testing them first isn't a sustainable way to maintain these vehicles.

Hi Offtrack how do you do this test please.

Type "MAF resistance" into the "Search AULRO ONLY!" box at the bottom left of the page.

The first result will point you in the right direction:
http://www.aulro.com/afvb/discovery-...ce-values.html

I've been trying to assist with this one and we've had the nanocom on the vehicle. No faults read for the engine.

Symptoms: The turbo is very slow to spool up, which makes it feel like the auto is the problem. No major spool up, even after 1500 / 2000 rpm. Fuel related problem perhaps?

The MAF is ok'ish , as per our tests (we swapped it out for a good one) http://www.aulro.com/afvb/discovery-...modulator.html.

It may be the boost modulator - we need to try bypassing it, as per this thread. Even though we cleaned the sensor on the inlet manifold, we could also try swapping out the oxygen sensor, if you want.

BTW: Tests done to date: Oil in the auto is clean and to the right level or perhaps a bit high even.
The nanocom indicated the MAF was reading a bit low, but ok. No resistance tests done. We swapped it out for a known good one.
Wastegate works ok. Tested with a bike pump - actuates ok.
Cleaned the sensor on the inlet manifold.
ECU connector clean (no oil).
No FPR leaks.
Checked the turbo on the inlet - no play etc.

Any other thoughts on why the engine takes forever to spool up???

Record the fuelling inputs with the Nanocom and post the file up here. If you can do a 10-15 minute recording covering a section with a hill climb where you can really put the foot down and get the turbo on boost, or overloading you should get some useful information about what the engine is actually doing.

cheers
Paul