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I need help with tf air conditioning only cools when parked
As soon as you drive hot air comes from outside
Any help would be great
Tks

Hi and welcome to the forum

Strange one, I'll give it some thought.

James

Jorge D wrote:
I need help with tf air conditioning only cools when parked
As soon as you drive hot air comes from outside
Any help would be great
Tks

When you say hot air comes from outside, do you mean the a/c is still running but is overwhelmed by a leak? Or that it starts blowing hot instead of cold?

What age of car? Small things like this might help with the diagnosis. Are you really in the USA?

Have you tried having the 'Recirculate' function on? That way only internal air is cooled.

Hello Yes the air starts to blow hot from the vents
It's 2004

Air recirculating on or off same thing
First I thought it was outside air coming in the cabin

But no its blowing hot

A stupid question, but what is the heater output setting? Is it on cold or on hot? The cabin heater/ air conditioning on the MGF/TF is extremely rudimentary

Has the system been re-gassed? If not it will never generate cooling.

OP said cools when parked. I was wondering if the a/c overlaps with the cooling system somewhere.

Normally on an air con system the system won't run unless the heater fan is switched on to at least position 1. There should be a warning lamp (green or yellow illuminated on the A/C switch if that is the case to show that the system is active. Given that the heater fan resistor pack is a very unreliable part in the MGF could this be a source of your problem? Failing that, when the A/C is activated are the front radiator fans running? They should be. You should be able to hear the clutch engage on the compressor when the system activates, and engine revs at tick-over may drop slightly when that happens.

Thanks all for the advice but I've done everything regas it's on cold fans are on cluch engages as soon as I drive to a stop light it starts cooling again
It's so weird I don't know and understand my town there are not good shops to rely on that's why Y need help

From what you say it sounds like there is ram air passing into the car without going through the air-con radiator in the heating/ventilation system. Not being familiar with A/C equipped MGF/TFs (they are very rare in the UK apart from the chinese ones) is it possible that there is a part of the trunking that's missing - warm air passing into the car directly from the inlet on the front bulkhead rather than passing through the cooled radiator in the fan unit.

Has the vehicle ever been accident damaged and had the dashboard removed/replaced? Is there a problem with the recirculating flap that's preventing air going into the unit and instead directing it into the cabin?

The recirculation mode works and no accidents
Where does it get the air Into the cabin
I found a inlet in the front hood that looks like a snorkel but I don't know if I can block that might be air going somewhere else

The air comes in through the snorkel through the A/C rad where it is cooled and then through the heater matrix where it is heated to what ever temperature the system is set to, the air is always cooled first.

I suspect what happening is that you have some air in the heater matrix and you have a faulty temperature control valve.
When the car is stationary and the revs are low there will be little coolant in the matrix so the cooled air predominates.
When you are moving more coolant is pumped through the system and heater matrix so the cooled air is now being heated.

I would start by checking all three bleed points to make sure there is no air in the system.
Once this is done you may well find that the interior fan blows hot all the time.
That would be the clue to check the temperature control valve operation.

James

Thanks James
Sorry for my ignorance
What are the three bleeding points and how can I check for that problem
Thanks again

One on the radiator, RHS when looking at it from the front. Second one on the heater matrix (you have to remove the under bonnet plastic shielding to get to it and a 3rd one on the engine coolant rail, best accessed after removing the engine access hatch.

Jorge D wrote:Thanks James
Sorry for my ignorance
What are the three bleeding points and how can I check for that problem
Thanks again

You are welcome

Lots of info here on the cooling system, there are lots of other how to guides on the site.