Idles fine till AC is turned on

[skippy]

tuning a tr230 cam in a 2001 camaro running SD
A/F looks good in the VE.
spark seems to be fairly stable
Idle is rock solid....except when I turn on the AC..
when I tun on the AC it surges and hunts and gets worse and wrose until it just dies.
what do I do to fix this?
what parameters do I change

[EC_Tune]

Need to look in Tq Management at Engine Torque. There are parameters to control the engine as the AC is applied & released.
Pay special attention to your spark advance when the AC is being applied.

I had to drop that spark table by 90% on a 402 equipped 2004 Z06 to get the engine to be stable when the AC came on.

Does the A/C click on & off a bunch when you turn it on the first time?

EC

[Billiumss]

Is this the table you are talking about? How does this table work, take out timing when the AC is applied?

Bill

[Perdieu]

I'm having the same issues. But some times mine works...

[EC_Tune]

Is this the table you are talking about? How does this table work, take out timing when the AC is applied?

Bill

Yep, thats the spark table. It pulls spark just before the compressor engages and then returns the removed spark after the compressor engages. Tends to make cammed cars stall or sag badly. Then it kicks the compressor off and repeats. Turns itself into a self-eating orange.

[Billiumss]

EC,

So start with 50% reduction and go lower as needed then?

Bill

[skippy]

I have an enable disable button...guess I'll try that...
wont be till next week ..have some slotted and drilled brakes put on

but yeah..its clicking on and off

are there any other tables in my 2001 a4 f-body OS that would help this condition??

[EC_Tune]

Billiumss
I would go at least 50%. Yep.

skippy,
You may want to look at the On Hold Time table. Shortening that table helped immensely on the 402 I was working on.

[Russ K]

Need to look in Tq Management at Engine Torque. There are parameters to control the engine as the AC is applied & released.
Pay special attention to your spark advance when the AC is being applied.

I had to drop that spark table by 90% on a 402 equipped 2004 Z06 to get the engine to be stable when the AC came on.

Does the A/C click on & off a bunch when you turn it on the first time?

EC

EC, I zero'd out that table. Made a great improvement when turning on the A/C on my 2001 ZO6 cam/header car. The timing used to retard ~ 20* when the A/C was turned on! Thanks for the tip.

Russ Kemp

[EC_Tune]

Russ,

Had a guy in Texas that said he could feel his truck slump at speed when the A/C came on. Fixed that table & the problem went away. Fuel economy went up as well.

[possum22]

You may want to look at the On Hold Time table. Shortening that table helped immensely on the 402 I was working on.

What do you mean by Shortening?
Here's my stock AC Torque-On Hold Time tablehttp://home.exetel.com.au/possum22/H...old%20Time.JPG

And here's one from a HSV 285 KW CLUBSPORT tune AC Torque-On Hold Time table http://home.exetel.com.au/possum22/H...old%20Time.JPG
thanks

[LS1_Sounds]

Does this table only exist on later year OS's? My car doesn't have it, but I do have something else under Engine > Torque Management > Engine Torque> AC Torque vs. AC Pressure. See attached.

[possum22]

Does this table only exist on later year OS's? My car doesn't have it, but I do have something else under Engine > Torque Management > Engine Torque> AC Torque vs. AC Pressure. See attached.

Mine has that table too, as well as AC Torque vs IAT -40 to 140*C
0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 1.35064 2.70127 4.07839 4.07839 4.07839 4.07839

[EC_Tune]

What do you mean by Shortening?
Here's my stock AC Torque-On Hold Time tablehttp://home.exetel.com.au/possum22/H...old%20Time.JPG

And here's one from a HSV 285 KW CLUBSPORT tune AC Torque-On Hold Time table http://home.exetel.com.au/possum22/H...old%20Time.JPG
thanks

Cut the values down by 20-50%. Maybe even more.

EC

[Billiumss]

What's the main purpose of those tables, to put less stress on the AC Compressor or engine?

[EC_Tune]

To make the transition from AC On to AC Off to AC On seamless.

[98A4LS1]

LS1_Sounds, same here, I don't have that table in my '98. ie AC Bump Torque.
Is there anything '98 owners can do?

[EC_Tune]

Hmmm. Earlier years only have the AC Torque table to play with.
Don't even know if these other tables "could" be available in earlier cars.