fans and temperature

[brb]

I've seen that my fans are switched on when the coolant temperature is at 93°C. so they're almost always in action. is it the good temperature release or is it too low ?

[R0162]

Your temp is not at 93, the fans kick in at 98 on the nobles, the temp gauge does not show the real coolant temp, the cars run optimally at 96deg but on the earlier nobles people were phoning saying the cars were overheating, so they did some program on the ECU to hold the temp gauge at 90deg, many manufacturers do the same.

The problem with this is you the first signs of a leaky coolant system the temps will creep above 90 on the dial, i.e showing 93, your actual temps may be 104, i think this is the stage you are currently at, sometimes pressure leaks only show up when the system is at working temp. I took my old radiator to get tested they put it under water and pressurized it to 2 bar, no leaks, but i knew it was leaking because i saw steam coming out of the seams whilwe in use, so i said submerge it in boiling water for 20 miutes and try again, this is when the cracks open up, so they marked the leak points and rewelded to keep me going until i got a new radiator.

When the car starts to overheat say 109 and above the temp gauge needle will start to jump and this tells you that the radiator is kaput or you have a significant coolant leak.

[brb]

thanks, but 93°C read in the ECU and controlled with an IR thermometer

[R0162]

fans kick in at 98, put a new temp sender and run to your gauge bypassing the ECU and you will see your real temps, you will be running above 100.

[brb]

R0162 said:

put a new temp sender

already done. there is just one temp sender ?

[R0162]

brb said:

already done. there is just one temp sender ?

I put a new one connecting to the dials and left the old one in place still wired to the ecu so on my system i have two, you can just bypass the ECU with wiring on your stock one, no need to add another, i just found adding another and not messing with the original was easier.

[SimonJW]

When I first had the ECU changed mine cut in at about 80 which meant they were on nearly all the time. I now have them cut in at about 98 and it cools to just under 90. Normal running I sit at about 80 on the dial.

Si

[joust]

The ECU actually has a map that maps input to output. The standard map has a flat part of the normal linear map to stop the needle wandering under normal use. All modern cars do this.

After (IIRC) 99 the map goes linear, which is why some people report the needle suddenly shooting up.

You can have the map changed by anyone that can map the whole ecu. mine is.

[joust]

Oh, also remember that if you have the air con on the fans run at slow speed all the time.

J

[brb]

is the temperature read with the noble software wright or wrong ?

[key750]

joust said:

The ECU actually has a map that maps input to output. The standard map has a flat part of the normal linear map to stop the needle wandering under normal use. All modern cars do this.

After (IIRC) 99 the map goes linear, which is why some people report the needle suddenly shooting up.

You can have the map changed by anyone that can map the whole ecu. mine is.

I have found in an american forum this images:





It's the same thing you say?

[mgbond]

Need to make sure you have an MBE ECU as its only this that controls the needle. Is your car a 3.0 or a 2.5 as the 2.5 temp runs from a thermo switch by the radiator and not the ECU, which why the 2.5's read the correct temp all the time.

Bondy

[TuxMan]

Yellowhed can alter your setup if you need to . Tux

[key750]

mgbond said:

Need to make sure you have an MBE ECU as its only this that controls the needle. Is your car a 3.0 or a 2.5 as the 2.5 temp runs from a thermo switch by the radiator and not the ECU, which why the 2.5's read the correct temp all the time.

Bondy

I don't understand, sorry.

I have a 2.5 MBE ECU and needle see allways 90° and not up... but sometimes fans starts!
You say 2.5 read correct temp all time... read but not show at the needle!

What do you think? I need to modify my car? because i live in Italy and here it's HOT!!!!!!

[brb]

mine is a 3.0, with a MBE ECU.
so, if I understand, the temperature read with the noble software is the same that at the gauge. am I wright ?

[joust]

brb said:

mine is a 3.0, with a MBE ECU.
so, if I understand, the temperature read with the noble software is the same that at the gauge. am I wright ?

Nope. The temp is "mapped" as the graphs above. It's right in the sense it the same as other modern cars, but it's not what's actually going on in the engine.