High Idle and Low Temp

[Blue4Ice]

I was driving the Esprit over the weekend to give it its weekly run during the cold season and noticed that the car was idleing around 1400-1500 and the temp needle wouldnt go above 79-80. THe temp has never high since I got the car but used to go around 81-82

The last time I run freescan (a few weeks ago) everything seemed ok. I know I need to run it again and will do so over the next few days, but any idea what would vause these symptoms? Perhaps a knackered thermostat?

Any advice always well received!

Edited February 6, 2006 by Blue4Ice

[hotrod3]

Sounds more like your temperature sensor under the manifold which sends the signal to the ECM and telling it that the engine is still cold. Does the idle ever come down to normal running rpm? If it does then its not that temp sensor. I think your thermostat would tend to make it run more towards the hot arena, if it were stuck open or shut.Only bad thing that happens at those temps is that your boost doesn't come into play until the engine warms up to about 81+ Check your connection at the thermostat housing,thats the VDO dash gage temperature sensor,you could be getting a false reading there too.

[Blue4Ice]

Thanks for that. Is there an easy way to test this is working? I cant remember now if that is contained within Freescan

The thing is though that I think I am getting boost ok (infact poss over boost). When I give it some the needle sometimes flicks up to around 1 bar (I know it should hit 0.85 on hard acceleration) but I dont always feel like I am getting a big kick in my back. The car is going on a RR at end of Feb so at least I can see if I am hitting the right torque and bhp

[Vulcan Grey]

The dash temp gauge gets it's signal from the sensor near the thermostat. The ECU gets it's signal from the coolant temp sensor under the intake manifold. If the ECU is sseing a cold temp and keeping a high idle, and the dash reads under 82C when it should be warm... Then the thermostat is bad.

I had a thermostat go bad once and the temp would never go over 80C, the ECU was also limiting boost.

I think it's just the thermostat, though a good cleaning of the electrical connectors can't hurt too.

[Blue4Ice]

The dash temp gauge gets it's signal from the sensor near the thermostat.  The ECU gets it's signal from the coolant temp sensor under the intake manifold.  If the ECU is sseing a cold temp and keeping a high idle, and the dash reads under 82C when it should be warm...  Then the thermostat is bad.

I had a thermostat go bad once and the temp would never go over 80C, the ECU was also limiting boost.

I think it's just the thermostat, though a good cleaning of the electrical connectors can't hurt too.

<{POST_SNAPBACK}>

Thanks for that. I think I will change the thermostat out of course. SJ appears to have the item for

[Blue4Ice]

Can anyone point me in the right direction to where the thermostat is? I have the manual on CD and was having a look earlier but I am finding it hard to orientate myself in the engine bay

Ta

[Vulcan Grey]

Can anyone point me in the right direction to where the thermostat is? I have the manual on CD and was having a look earlier but I am finding it hard to orientate myself in the engine bay

Ta

At the front of the engine, just above the cams, in the gooseneck of the pipe that the belt runs through. Follow the big aluminum pipe that arcs over the alternator and look where it ends on the left side of the engine. There are 2 bolts holding the thermostat housing together.

[Blue4Ice]

At the front of the engine, just above the cams, in the gooseneck of the pipe that the belt runs through.  Follow the big aluminum pipe that arcs over the alternator and look where it ends on the left side of the engine.  There are 2 bolts holding the thermostat housing together.

<{POST_SNAPBACK}>

Cool thanks for that. I am about to go and run freescan to see if that chucks anything up and will buy a new thermostat over the next couple of days so I can rule that out