I have a car that I am tuning and for some reason when you turn the A/C on the idle goes to crap. It hangs really low and doesnt seem to recover. Its a 6 speed car with a G5X3 cam. Any ideas?
Phil

 

What kinda timing are you pulling. I tried calling your cell but it keeps going to VM

 

My freakin cell is dead AGAIN. Someone said that there is a table under torque management that works with this..
Phil

 

Bump the Fan airflow #1 and #2. Fans come on with AC. Stock values mine - 0.2 and 0.4.They are 1.0 and 2.0 now.

Also, might bump AC learn limit in gear - stock 0.50(?). Then it will be able to store a greater value than 0.50 in the Idle Learn RAM.

 

Ditto.

Try .6. If it's still crap go to .7.

 

What programmer are you using...In HP Tuners, there is a section for Base Spark vs. Airlfow vs. RPM Throttle Closed...

I've been trying to smooth the idle at 1000 rpms for a couple months...Finally, the other day I noticed that at 1000 rpms I had 20 deg. advance, then almost instantly, with no throttle change, the timing would jump to 34 deg. advance and the rpms would rise to 1200...So, I adjusted the timing in the Main Spark table to raise the lower rpms timing...Next day, same exact timing, 20 deg. then up to 34 then back to 20...Couldn't figure out why...Then I went into the Base Spark table and sure enough at 1000 rpms, it called for 20 deg.

What was happening, was the PCM was going back and forth between the Base Spark Table and the Main Spark Table...

So I went in and raised all the Base Spark values by 8 deg.

Now, it doesn't transition from 20 deg. to 34...It idles at 28 deg. then transitions to the Main Spark table very smoothly...

Reason I'm telling you this, is if you are raising the Main Spark timing for the G5X3, which I added 5+ deg. to nearly every value in there, relative to stock timing...

You need to go into the Base Spark and raise those values...It should idle much better...

I use 975 rpms, A/C off and 1050 rpms, A/C on and it never dies and rpms never drop below 900 when you get off the throttle...

Also, if you haven't done this already...You need to drop the values of the 5 colums of the VE Table...400 rpm column multiply by 0.85, 800 rpm column mult. by 0.88, 1200 rpm column mult. by 0.91, 1600 rpm column mult. by 0.94, and the 2000 rpm column mult. by 0.97...

Runs very smooth and throttle response throughout is excellent...

I can e-mail you my VE, MAF Freq., and Timing Table in Excell format if you wish to see them...

Peace...Gman

 

This is interesting. I've been dealing with trying to smooth out my idle too and was checking out all the timing tables. I can see why the timing going back and forth between tables would cause a problem. Gman, what's with the 2 base timing tables, Drive and Park? Which table does the M6 cars use as the base table?

 

In Drive

 

How about when you raise the idle to 1200 rpms and adjust timing, or manipulate the IAC and everytime your at idle, turn the AC on the car stalls? If your driving it works fine. I think the compressor is jacked up or over pressure maybe. But tried about everything and no work.

 

HavATampa...I really was not sure which it would use, so I made just both tables identical...

Peace...Gman

 

If the car is at idle and moving the "in gear " table is referenced. If it's stopped - "Park/Neutral".
There are some defaults within the code where the timing will drop to the lowest available value ( Usually the Park table). These seem to be mostly related to PCM percieved Lean condition. At least on a 2001 Z06 anyway.

For AC problems increase the AC Max offset table. Stock is about 0.50 g/sec. You may need to go much higher - 4.00 g/sec. Also increase Airflow offset for the fans...stock .2/.4 g/sec may need up to .75/1.5 g/sec. (The bigger the cam and narrower the LSA the more offset you'll need.)

 

This is starting to make sense, thanks guys! I ended up making the idle portion of both tables identical for timing also. Would it hurt to make the idle portion in the high octane table identical to the drive table also?