Air conditioning on dual fuel

[85_Calais]

Hi,

My car has a problem at the moment where if I drive it for more than about half an hour, the air conditioner will stop working. Air keeps blowing through but it's not cold. It's hard to tell if the compressor is still going or not.

What's weird though is that I can usually fix it by changing from gas back to petrol. Has anyone got any idea what may be causing this?

[Paiste402]

im guessing in that case it would be more of an electrical thing since the pump when working just needs to be spun and LPG is just a fuel. Hmmm, maybe there is a short somewhere and flicking the electrical fuel switch would do something, or maybe ur low on gas in the air con system...

[85_Calais]

im guessing in that case it would be more of an electrical thing since the pump when working just needs to be spun and LPG is just a fuel. Hmmm, maybe there is a short somewhere and flicking the electrical fuel switch would do something, or maybe ur low on gas in the air con system...

Yeah it happened the yesterday again when it was 38 degrees and this didn't fix it. It has recently been regased and has a new condensor. I think it's just f***ed! It's hard to demonstrate to the auto electrician because to make the problem happen, the car is too hot to work on. I'm thinking now it may be a dodgy thermostat, or dodgy electricals like you said, and maybe me flicking the fuel switch is enough to send a surge through the system to get it to work?

[Paiste402]

Yeah it happened the yesterday again when it was 38 degrees and this didn't fix it. It has recently been regased and has a new condensor. I think it's just f***ed! It's hard to demonstrate to the auto electrician because to make the problem happen, the car is too hot to work on. I'm thinking now it may be a dodgy thermostat, or dodgy electricals like you said, and maybe me flicking the fuel switch is enough to send a surge through the system to get it to work?

is ur car overheating to where you think u need a new thermostat? All the thermostat does is control how much coolant goes through the engine at a time, keeping it at a steady temp. Hmmmmm, now ive never played with an air con system but again it seems like an electrical fault since everything mechanical has been overhauled. If you cant see a loose wire on the system on the outside all i can think of is to have the pump removed so the internals can be looked at. Worse come worse you could just get a re-conditioned pump from a wreckers and put that in, then if the problem persists you then know its not the pump. Not the kinda thing u wanna go through but if u want it bad, u gotta go the length.

Im leaning more towards just gettin a different pump that is known to work just to cut the crap and the money spent in testing and removing, ungassing, regassing ect the pump uve got.

Best of luck mate and let me know wat happens

[commsirac]

What you really want to know is whether power to the compressor is dropping away and it is "reignited with petrol"
Does the motor idle speed drop when the air is first turned on, or is there some idle compensation built in. If it does drop, do the rpms drop to that value when its putting out warm air.

Alternatively, find the wire tht goes to the compressor clutch and splice a wire into it and have it run inside the car and wire a led or test lamp up to it. You'll be able to see when the compressor is getting electrical power while you are driving and determine whether the problem is in the electricity supply or mechanical side of the ac system, this is what the autoelec should have suggested....it should only take 15mins and about $2 of materials to setup.

Cant at this stage really think of anything that would cause the aircon to work better when petrol is selected, other than something weird happening with the perhaps water starting to flow through the heater core....but thats a long shot.

[85_Calais]

Cheers for the advice guys. Looks like I'll just need to go over the electricals carefully.