VW question in the Benz board

[SCOTTFISH]

I have 2 benz's and frequent the board, but I have another German car that I need to ask a question on and hopefully you too have a toy that you can guide me on. I have a 90 vw cabriolet that has ac and is a 5 speed. When the ac is on and you are coming to a stop like at a light, when you push the clutch in and apply the break, the rpm needle will fall down as normal,but then keeps going and sometimes chokes out to where you have to start the car back. Could this be a vaccuum leak? It only happens with the ac is on. Without the ac, the same process, but the rpms will drop as normal down to idle and hold. Anyone ever experienced this? Your help is appreciated. Thanks. Scott

If it's a diesel and still has good compression.I would think it's either a timing problem with the IP,or a fuel flow problem.If you'r asking about a gasser,I would start checking all the vacuum hoses.Don't just glance at them.Pull each one off individually and replace any that aren't perfect.My wifes gasser Cabriolet convertible had the same problem this spring when we took it out of winter storage.I had to replace almost half the hoses.Lots of small vacuum leaks.

[spanish cossie]

not sure of the ins and outs of your VW but in general when you turn on the air-con there is a compensating rise in RPM to off set the extra load, it sounds as if your car is not doing this and the extra load of the air-con is dragging your tick over too low.

[Jim's500E]

Sure sounds like it could be a vacuum leak...try www.vwvortex.com - they have a A1 Cabriolet forum where ALL your questions will be answered. The Scirocco forum has done me well over the years.