Wanted to post here to see if anyone has come up with a good solution. I have an A/C system on my 40 year old Type 4 with L-Jetronic FI. When its on it pulls quite a bit of power, to the point that it will stall my engine unless I set the idle pretty high (ie like 1200 RPM). I don't use it all the time and dont enjoy having the engine idle this high when it is off. I read that in more modern cars a solenoid valve is used that creates a vacuum when the AC system is switched on to push the idle up. Has anybody here plumped such a solution into their car and if so what parts did you end up using? My AC pump is a Denso. Thanks for sharing!
Jason
Type 4 & A/C idle
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Re: Type 4 & A/C idle
You can set up a simple arrangement that works with a fast idle valve off a lot of cars. and just have the AC turn it on with the compressor clutch. It won't have enough flow to be noticable off idle, but a lot of old cars had idle and WOT switches parially for that reason.
Ideally you would have a fairly large valve and a means of turning that airflow down to suit for a custom setup, a restrictor inlike works too.
This was ~how all OEM factory setups were pre-computer,(everyone, not just VW) compressor power was also usually routed through a WOT switch as well so it cut off near WOT.
(Engine has more power and compressor lives longer disconnected if you are exploring upper rev range, at least on a modified engine)
Ideally you would have a fairly large valve and a means of turning that airflow down to suit for a custom setup, a restrictor inlike works too.
This was ~how all OEM factory setups were pre-computer,(everyone, not just VW) compressor power was also usually routed through a WOT switch as well so it cut off near WOT.
(Engine has more power and compressor lives longer disconnected if you are exploring upper rev range, at least on a modified engine)
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.