16v Engine Stalling and Air Conditioning Issues

Topic: 16v Engine Stalling and Air Conditioning Issues (Read 647 times) previous topic - next topic

16v Engine Stalling and Air Conditioning Issues

January 19, 2023, 07:11:46 AM

Tres embarrassment today…..I broke down

It’s 38+deg C here in Melbourne, Australia and I was driving the mk2 in traffic. With the aircon on high, I would pull up to stop and the car would not catch the idle in time and stall. When I turned the air con off it would catch the idle as normal.

Anyway, I was experimenting to see if there any other symptoms and I stalled and couldn’t restart as the starter was too hot.

10min it’s in the side of the road and I was good to go again.

I have done some diagnosis today. Cleaned the isv In petrol overnight and then with contact cleaner whilst ‘on’. Connected all back up and ISV seems to work fine. I have been checking voltage drop when the ac is on.

Without ac I get 13.8/9V across the battery. When I turn on the ac the voltage at the battery drops to 12.5V. I’d say this is definitely the issue as the idle system is voltage sensitive.

I guess the next step is figuring out where the high draw is: compressor, rad fan(which turns on with ac)…..ideas?

I will also go get the battery load tested.

(the 16v has just one isv that is controlled by an idle control module in the dash, which has an input for the ac to tell the idle to go higher)

Re: 16v Engine Stalling and Air Conditioning Issues

Reply #1 – January 19, 2023, 09:03:07 AM

Quote from: dubstar on January 19, 2023, 07:11:46 AM

Tres embarrassment today…..I broke down

It’s 38+deg C here in Melbourne, Australia and I was driving the mk2 in traffic. With the aircon on high, I would pull up to stop and the car would not catch the idle in time and stall. When I turned the air con off it would catch the idle as normal.

Anyway, I was experimenting to see if there any other symptoms and I stalled and couldn’t restart as the starter was too hot.

10min it’s in the side of the road and I was good to go again.

I have done some diagnosis today. Cleaned the isv In petrol overnight and then with contact cleaner whilst ‘on’. Connected all back up and ISV seems to work fine. I have been checking voltage drop when the ac is on.

Without ac I get 13.8/9V across the battery. When I turn on the ac the voltage at the battery drops to 12.5V. I’d say this is definitely the issue as the idle system is voltage sensitive.

I guess the next step is figuring out where the high draw is: compressor, rad fan(which turns on with ac)…..ideas?

I will also go get the battery load tested.

(the 16v has just one isv that is controlled by an idle control module in the dash, which has an input for the ac to tell the idle to go higher)

I have to be honest, I'm not sure how much help you'll get from us. Air-con is very uncommon in UK cars... all you'll get is envy

Re: 16v Engine Stalling and Air Conditioning Issues

Reply #2 – January 19, 2023, 12:12:24 PM

You'll definitely get envy here!!

As for the current draw, see what it drops to when you stick your lights on and the normal fans/rear window heater.
Bet you'd be close to that 12.5v.

Also, you could try (very briefly) disconnecting the radiator fan and then trying the ac again, see what the voltage is and if it stalls the car.

Re: 16v Engine Stalling and Air Conditioning Issues

Reply #3 – January 20, 2023, 02:58:32 AM

Thanks for the responses. I am going to check the draw with and without the blower and the rad fan.

BTW, I also find it really hard living close to the beach, especially when it’s warm and you have the sunroof open.

Re: 16v Engine Stalling and Air Conditioning Issues

Reply #4 – February 22, 2023, 10:28:23 AM

My sympathies - it must be really hard for you!