Hi all, do you own a 2003 onwards 3.0, if yes can you let me know your normal running temp by useing the engineering test mode dash read out?

If you don't know how, read below-

Push and hold in the button on the left indicator stalk, then start engine, it will say test mode where your miles would be.
Now, use the same button to advance thru all the modalities until you come to 'TEMP IN 765' which is coolant temp 76.5c.

Thanks Simon.

 

Will do - are you the same guy who asked this on the UK forum btw?

 

He must be. No-one ever went this route before.

76.5 must indicate a fault if engine was up to temp.

 

Just been out for a run in mine, it settled at about 940 but reached 955 whilst sitting in traffic. It's a fairly warm day though and I had the aircon on, the needle didn't move from the centre of the dial.

 

Yes its me! Just trying to get as much inf as poss.

Yes i think i have a problem, the temp gauge sits just below the half way point and dash read out says 76c and thats after 2 hours drive. I just changed the coolant senser and have removed thermostat housing (it looks new, so must of been replaced by the last owner) and removed thermostat and tested it and it starts to open at 89/90c, refitted and its still the same.
Also checked pipe layout in JTIS and its the same, cooling fans not on!

So why is my engines normal running temp not the same as the opening of the thermostat?

 

Poor flow? Bad circuit for sensor? Something else... Need to think up things it might be and get testing

 

Well i found the problem, i disconnected the coolant sensor and plugged the old one back in with it sitting in a plastic cup which was half full of water (which i just boiled) with a thermometer also sitting in the cup. Then started car with dash in test mode and dash reads 65c and thermometer 80c, watched temp as water cooled and dash allways reads about 20% less.

So before then my dash said running temp was 65c the engine would be around 89/90c! So i must have a wireing fault between sensor and ecu

 

Makes sense, I can think of lot's of reasons for it to get too hot, but too cold is trickier.

 

Also worth checking you have not had water getting between windscreen and seal so that it can seep across and onto the PCM. Unusual, but has been known.

JTIS shows wiring, even splices if you look, but still may be painful checking all places out.

 

Cheers, problem is now find the faulty wire!

 

Good luck!

 

Cheers, I think i need it.