Volvo 480 Club Europe

The Celebration seems to start with a high idle speed , around 1200-1500 then drops back to just above 1100 after a few seconds

the two litre starts at just over 1000 and drops back to below 1000 (NO air conditioning)

is the high start idle normal on AC equiped cars or is this unusual?

also the revs tend to sit a little higher (or hold) when dip the clutch to change gear, again is this a feature of the ECU to prevent the negine stalling when the AC would be running? I'd have assumed that if the AC is 'off' then the ECU would know this and so leave revs a little lower, AC is goosed, but TBH I never notice if I have physically switched AC off , which I probably should try?

I just jumped out and checked mine.

Celeb with a/c and it does the same 1400rpm then drops.

arthuy wrote: ↑

Mon Apr 27, 2020 9:37 pm

I just jumped out and checked mine.

Celeb with a/c and it does the same 1400rpm then drops.

Ditto

Thanks guys, saves me trouble shooting a non-existing problem . . . . .

still think it's a bit high, I'd prefer a lower speed to let the oil circulate at start up!

Alan

I remember noting this because I didn't remember my previous Celebration doing it. Given I drove it for over 6 years I felt I should! However it never seemed to be a problem so I just accepted it.

My current Celebration does exactly the same, so given the replies on this thread I guess it's normal...

Not sure why though. I too can only assume it is something to do with having aircon fitted as standard and the ECU being set up accordingly. But my GT doesn't do it all the time, and that, too, has aircon as standard. Unlike the Celebration it works properly too so I do use it. When aircon is on the GT seems to maintain slightly higher revs between gear changes - perhaps it senses and compensates, then by 1995 Volvo simplified things and just set the ECU differently on aircon cars?

Nominally the 2 cars have the same ECU but the reference number on the GT ends in "b" and on the Celebration in "c", so presumably there must be a difference...

David

dcwalker wrote: ↑

Fri May 01, 2020 10:16 am

When aircon is on the GT seems to maintain slightly higher revs between gear changes - perhaps it senses and compensates, then by 1995 Volvo simplified things and just set the ECU differently on aircon cars?

yes that's what I'd have assumed, with air con ON the engine would probably 'bog' if revs were not kept up a 'thochty'.

I could try and swap to one of the spare ECU I have, if nothing else to prove that they work and are not just 'ballast'. used to leave one of the spare under the passenger seat so could be swapped out if required at roadside