AC without jumping 1Q and 1J
 

Having trouble with the above.
1J connected to INJ G. 1Q connected to NitrousIn.

AC switch works, blue light goes on. INJ G toggles the AC relay.

Can't see the voltage change on NitrousIn, when ACsw toggles. Either in TS, or with a volt meter. I *think* I jumpered JP8 on the MS3X.

Any thing else I can check? I'm sure my output logic may stink, but if the MS3 can't see the input, it will never be able to output correctly.

Has anyone done something similar to this?
Thanks

So much fail. I had connected Nitrous In to 1O, not 1Q.

To see if anything was working I jumped 1J to 1Q and disconnected INJ G. AC comes on. However idle up does not seem to work. If I let go of the throttle, the car stalls. Can I use Nitrous In as an idle up signal? Or would it be better to use launch_in?

Nitro In is fine, what idle % adder are you using?

You should be using about 12% adder with a 250ms delay. If it's stalling with/without an adder, you have poorly tuned CL PID.

AC Idleup Settings
 

I had an idleup delay of 275 ms, compressor delay 5 sec, IdleUp Duty % 7.4, Idleup target increase of 100 rpm. (Default settings probably)

So I should change to 250 ms, 12.2%?

NitrousIn is a bit confusing - isn't it supposed to be active high? The documentation is unclear to me.
For idiots like me, :noob: please confirm (again) that NitrousIn is ok for idleup.

Thanks

oh yeah. use datalog in, thats what I always use. or tableswitch, you have to add/remove a jumper if you use nitro in. I forget which, it's in the docs, you might be causing a ground fault the way you have it now.

Nitrous in is an active high input. Grounding an active high output will not trigger it. You need to use any of the active low inputs--tableswitch, launch, or datalog in.


http://www.msextra.com/doc/ms3/Gener...s3x-wiring.png


If you must use nitrous in, a jumper must be added on JP8. This will change the input to active low.
https://www.miataturbo.net/attachmen...ine=1372120810

Lean on AC on
 

Moderate success! :party: Wired in Launch Input, rather than nitrousin. Idle up seems to work - no stalling.

However, when the compressor is on - the AFR is 16-17, when compressor is off - afr = 14.3.

I tried editting the idle ve table to have two different zones. The afr is still poor when ac is on. MAP goes from 28.5kpa to 40kpa with the AC compressor on.

Enclosed is a datalog with ac compressor cycling (by itself, not by my changing the switch). Also an msq.

What can I change to make the afr better for the ac on case?

This is with the fan set to low. If the load were higher, (headlights, high fan), I'm not sure the engine would run.

Thanks for your help so far,

-Bruce

That's what I do. Have a 30kpa and 40 kPa row for w WO ac

So I need to add a lot more fuel to the 40kpA cells near 850-1000 rpm?

here's mine:

https://www.miataturbo.net/attachmen...ine=1372600409

IIRC I idle at 30kPa without a/c and around 45kPa with, so I have two rows for each pretty much and I stay in between them. I asked Ken for a/c to be able to trigger that second table, but he kinda brushed off the idea...

FWIW, I had a similar issue trying to use Nitro IN as an active low. I got this from James when it wasn't working as expected:

Unsure why they bothered to design in the optional JP8 pull-up jumper to 12v if this is the case.