I had several bits of work done on the car over a short period of time including a new compressor for the air con, some electrical work and other stuff.

Shortly after that the engine would stop. It did not matter if I was slowing for a junction, stopping at traffic lights or decelerating.

Quite scary at times to find you suddenly have no power steering, heavy brakes and no engine power and you have to pull over to the side of the road quickly before you get rear ended.

I went to a new mechanic when the air con packed in working. He renewed the gas and also added oil to the air con compressor (g/f's translation). Since then the engine has not cut out once and the work was done 2 weeks ago. The idle speed is better too and now does not keep dropping down to 2/300 rpm on tick over.

Does that make sense to you mechanically minded guys out there? (I've not had air con before coming over here).

And it is an Auto box.

Sounds like your new guy adjusted your tickover speed back to the manufacturers recommended speed. The air con does put extra load on the engine and if the tickover is too low, this would cause it to cut out on deceleration as described.

The aircon compressor could definitely put even more load on the engine if it didn't have enough oil in the system. If this was truly the case and lack of oil was causing the engine to stall at low speed / idle then you might be splashing out for a new compressor shortly.

If it really was the air-con compressor shutting the engine down due to a lack of oil, it will be severely damaged inside.

Cheers for that. It was a new compressor approx 3 months ago. From the comments above I would conclude the mechanic can't have made sure there was oil in it. I hope it does not pack in on me.

Thanks for the confirmation on the oil in the compressor. I had been wracking my brain as to the cause of the stalling and not having air con in a car before did not even know it needed oil, much less that lack of oil could cause such problems.

We live and learn

Cheers

also tune your engine properly. i had this problem also before but it was not due to compressore. Just needed to tune the engine properly and it was just fine..

If your aircon pump is damaged or over pressurized it will sound a bit like a machine gun. Not sure about modern pumps but they have 5 or 6 pistons, just like an engine and if there is no oil in the gas the cylinders wear out and make a racket.

automotive a/c compressors are since many years rotary type only. but like the ancient piston compressors they need oil too. i'm not surprised that the lack of compressor oil choked the engine but i'm surprised that the compressor survived.

And if the compressor seized, I would also expect to hear a fanbelt squeel.