Blue02Ws6

iTrader: (3)

I think that my air-fuel ratio is off some, and my timing could use some retuning. It looks like my car will not go 100% full throttle either, the pedal was through the floor. Also, what IAC parameter should I be using to adjust idle on my car, and what should the ideal number be for that setting?

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<small>[ December 23, 2002, 11:14 AM: Message edited by: Blue02Ws6 ]</small>

Colonel

You and I use different versions of Autotap so I can't say for sure that your version is even capable of moitoring the IAC. What I use in my DOS based version is "IAC Pintel Postition Counts" best I can remember.

Your O2 sensors DO NOT read accurately during open loop operation. Only during closed loop. They were designed to read accurately only close to stoic fuel/air ratio. Your 11.5:1 could be 13:1 for all you know.

You should see about 26 degrees at WOT at high rpm...meaning 6000 or so. Higher intake air temps can lower this. Any amount of KR at any time will lower this. Even KR from a prior run can lower the timing advance. (In other words, don't assume that no KR on this run means that you never have any.) You can only get a good idea of your KR through monitoring on many runs. And yes, running too rich can lower the timing advance too although lower timing advance does not necessarily mean that you're running rich.

Blue02Ws6

iTrader: (3)

well, I just went to a good exhaust shop here in town and the last people that built a y-pipe for me sucked ***, there was a HOLE about the size of my thumb right behind my 02 where the y-pipe had rubbed in the header. The shop had to patch my header and now are making a y-pipe for my car, could this have been why my car has been screwing up?

Colonel

That information doesn't tell me a thing about your WOT mixture. What I look at is B1S1 and B2S1 in MVs. You can only get in the ballpark using O2 readings but usually .870-.910mv is fairly close...but sometimes it's not. It's best to use a wideband O2 sensor.

Idle Air Control Motor Position, you want it around 25-35 with the engine fully warmed and at idle.

You're probably right. Your throttle isn't quite opening all the way. In fact, even if it reads %100 it probably isn't opening all the way. That's how they are from the factory and is why the throttle stop mod is such a popular one.

Blue02Ws6

iTrader: (3)

Colonel, my IAC motor position sensor must be screwed up, because it was never moving from the 0 position. None of that data tells you anything? Should the air/fuel ratio be higher than it is there? Also, I thought timing should be around 26 degrees at wot.