Mg Zt cdti been in garage for years

[malc777]

Hi all.
Happy to be here in the MG forum and hello to everyone.
I recently had a 2004 Last of the old shape MG ZT CDTI gave to my by a very unwell family member.
The car has been in a carport for 4 years and i started it regular every few months in that time so i know it turns over ok.
Now as soon as i turn the ignition on the fan is going at full blast and it wont stop unless i turn of the ignition or turn car off.
It never used to do this so no idea what has happened to it.
I always knew there was a problem with the thermostat it would get colder going down a hill and hotter going up one.
I went out today and bought the renault thermostat with clips so will fit that this week on the top hose and hope that sorts that out.
But any idea why this far is running at full blast. I have played about with the aircon and stuff but it does nothing to this. I would think this is the rad fan at that speed and noise.
I am looking to put the old girl back on the road and any help would be appreciated.

[BigRuss]

Welcome to the forum
The fan on diesel models runs as soon as the ignition is turned if the air conditioning is on auto or the de-mist is on, press the econ button on the air on panel the fan should stop

Russ

[wuzerk]

it is perfectly normal for the temperature on the diesels to go down when
the engine is off load (going downhill) and to go up (going uphill), but you should not see any difference on the temperature gauge,only via the OBD.

[malc777]

All the aircon is off and temp is off. As soon as i start the car the fan is running at full blast and wong go off. There is something wrong with it and from what i have read they are common for faults.
Any ideas how i can repair this or is a new fan job?. Thanks

[Lee T]

Not normal but is usual for our cars. There is a mod to the upper rad hose where a thermostat is inserted and that usually resolves the issue and is much easier than the OEM stat to do.

[Mickyboy]

Originally Posted by malc777

Hi all.
Happy to be here in the MG forum and hello to everyone.
I recently had a 2004 Last of the old shape MG ZT CDTI gave to my by a very unwell family member.
The car has been in a carport for 4 years and i started it regular every few months in that time so i know it turns over ok.
Now as soon as i turn the ignition on the fan is going at full blast and it wont stop unless i turn of the ignition or turn car off.
It never used to do this so no idea what has happened to it.
I always knew there was a problem with the thermostat it would get colder going down a hill and hotter going up one.
I went out today and bought the renault thermostat with clips so will fit that this week on the top hose and hope that sorts that out.
But any idea why this far is running at full blast. I have played about with the aircon and stuff but it does nothing to this. I would think this is the rad fan at that speed and noise.
I am looking to put the old girl back on the road and any help would be appreciated.

Hi it could be the engine coolant temp sensor is faulty and automatically sending the wrong signal to the ECM that's setting into a safety mode of full speed it's better to run the engine cold than allow it to overheat it if you get the point,
I believe this is a safety measure, if you replace the engine coolant temp sensor you're probably resolve the problem in my experience.
The same would happen if you disconnected the engine coolant temp sensor.
Regards mick,

[grivas]

Originally Posted by malc777

All the aircon is off and temp is off. As soon as i start the car the fan is running at full blast and wong go off. There is something wrong with it and from what i have read they are common for faults.
Any ideas how i can repair this or is a new fan job?. Thanks

Hi there, sorry to state the obvious, but how much coolant is there in system, check level, and report back please

[malc777]

The coolant is fine its on the level where it should be. Strugglig to take the front bumper off as the screws that run along the front of it are threaded do i have to take all of them off?.
I will order a top temp sensor for it but from reading a lot in your forum is would suggest that the RESISTER maybe failed and that is why the fan is constantly running?.
I looked throught the vent but cant seem to see the resistor so know idea if this is a 2 speed or 3 speed fan unit. So kinda in limbo as in buying a resistor from ebay till i know.
Really need some help on this guys as its driving me mad and want to get it on the road.

[malc777]

Is there anyone on here that sells the top temp sensor or resistor?.
Mine is a 26/3/04 mg zt cdti last of the older shape.
What fan unit would this one have the 2 speed or 3?.
Thanks guys

[T-Cut]

Before buying anything, check the position of the temperature gauge needle when the ignition's on. If it stays on the bottom stop, then there's no signal coming from the sensor. That's almost always due to a bad connection, either in the connector itself or a break in the wiring. Pull the connector off, clean with a spray of some kind (WD40) and reconnect. If the fan still runs at ignition on, check the wiring from the connector. If neither works order your sensor, but in truth they rarely go wrong.

As for the fan type, look for an aluminium resistor fastened to the framework behind the fan blades at 2 o'clock position. If so, it's the later 2-speed.

TC