When is the AC mod needed in a flash

[German850R]

I doubt the problem is the actual compressor. More likely the CC unit. I don't understand though, you converted it to m44 and put in a new motor and never tested the AC?

Yes. I never tested it as the car is not finished yet anyways. Currently I have no AC lines in the car as the old ones look like crap. But for next summer I will put everything in again and try it.

[erikv11]

... Best way to tell is to just stick the m44 with the new bin in, and see if the a/c suddenly refuses to work.
Then  you need the ac mod.

Yeah OK, this is the take-home, and not hard to do.

We are using a 607 bin so we will now do the AC mod, and keep an eye if the compressor turns on and off correctly.

[Piet]

So, let's assume I have a 850 from 1997 which came with a M4.3

It is now converted to M4.4, an RN engine and a AC compressor from a 99 vehicle. Would this need the mod or not, or in other words: is the compressor the driver for the requirement of the mod or is it something else?

Yes, you do need the MOD in that case.

It's not the compressor that determines if the MOD is needed, it's just the victim when you do the AC mod in a car with the newer style CC unit.

 

For more information  : http://volvospeed.com/vs_forum/topic/159506-tuners-rejoice-free-tuning-for-m44/?page=328#comment-2368805