Has anyone ever considered (or implemented) a method for upping the idle speed when the A/C Compressor is engaged?

 

Hi Mate,

Analogue cars need analogue adjustments.

Run your static idle a little higher so that when the A/c kicks in the drop in revs doesn't have the engine wanting to stall.

My idle is 900 rpm so that when the A/c compressor kicks in, revs drop to 750 rpm, which for me is give or take 50 rpm above where my engine starts to want to stall.

I haven't had any related issues using this method.

Others my have other ideas.

Cheers,

Nigel

 

If we're talking about a Series III (or late Series II) with the fuel injected 4.2, Jaguar made an 'idle up' kit. It was actually standard fit for a couple years in a couple different markets. Every so often one of the kits comes up on Ebay. I can send details if interested.

But....in all reality...it might just end up being extra work for not-all-that-much benefit, IMHO

The compressor operates in all climates control modes, even when heat is called for. And the vast majority of people drive with the climate control 'on' at all times....so it's easier just to tweak the idle to what you want it to be with the climate control 'on
and call it good.

The downside, of course, is that the idle will be a bit too high on those occasions where the climate control is turned 'off'.

Cheers
DD

 

I should really add a signature, shouldn't I. Car is a 1987 XJ6 - so I'm definitely interested in details of the Jaguar solution that you mention.

I've done exactly that - upped the idle speed to the max so that I get sufficient idle when the compressor is running to keep it turning fast enough for it to work worth a damn when stuck in traffic.

I do have a switch on the compressor to turn it off when not needed, so when that's the case the idle is way too high, hence my desire to control it more elegantly.