Need Help!

[02GTP]

I have been trying to make this thing idle for too long now. It will idle ok for a little bit then surge and then almost die (sometimes it actually does). When its surging it will go from 22 to 1 AFR to 10 to 1 AFR. When it runs good its 14.X to 15.X which is great. I don't know if its reversion from the cam or what but I can't seem to get it and I'm at my wits end. I will even pay for a pro to look at it and help.

Car is a 2006 GTO M6 with a 231/235 LSL lobed cam. Vararam, Lt's, no cats, ported FAST 92. It was doing this long before the FAST 92. WOT its perfect and once its in gear and moving, it drives great.

I understand final tweaking will have to be all me, but if someone see's something way off or can help point me in the right direction that would be great.

[mowton]

Make sure your VE and MAF are tuned well in the idle areas. Without a log, I would put the Proportional idle values back to stock and mess with the minimum air in the idle area's a bit.

With that cam, the VE normally needs to be reduced by like 20% in the idle aand low load/rpm area's as a start.

Ed M

[02GTP]

I did add to the idle air minimum, which helped get it to idle better. I'm thinking the fueling is what's messing it up, can I force open loop just at idle? I think that would solve my issue.

Any benefit to disabling spark smoothing?

[mowton]

I did add to the idle air minimum, which helped get it to idle better. I'm thinking the fueling is what's messing it up, can I force open loop just at idle? I think that would solve my issue.

Any benefit to disabling spark smoothing?

My point is the proportional idle air adjusts are for dynamic changes as required where the min air will add that amount of air all the time. Like the over/underspeed timing, you set the base idle timing to something in the midlle and the adjustments can toggle up and down around the noiminal to provide adjustments.

Bill Winters has a technique for setting the min air where you actually use the over/underspeed timing to make % adjustments to the Min air to find that nominal level of Min air. They start with the stock idle proportional air values. Search the forum to find the actual procedure.

I have basically the same cam in my LS2 build running on an 411 PCM and it idles great. The E38/40 setups make this even easier.

Ed M

[02GTP]

I actually got it working perfectly. The problem was the VE table. It was stock so I found a modified one from a torquer v2 (which is pretty similar) and set the idle speed spark adjustments back to stock and it works like a charm, thanks for the info on the VE table.

[mowton]

I actually got it working perfectly. The problem was the VE table. It was stock so I found a modified one from a torquer v2 (which is pretty similar) and set the idle speed spark adjustments back to stock and it works like a charm, thanks for the info on the VE table.