While playing around with my datalogger tonight trying to resolve my hi boost miss (which today became a low boost miss also), I discovered that my timing at idle is all over the place. Like as high as 12-14 degrees and as low as -1.0 degrees. That's right less that 0 degrees of timing.:wary

What could cause this? The timing bounces constantly at idle, but if I go up to even 1400 rpms it smooths out and stays steady. This thing is driving me NUTS!!:o

What should the timing be at idle? I am going to hopefully datalog my car this weekend.

I datalogged this afternoon and i found that this is the case also. my timing below 1000 rpm is anywhere from -4 to 10 or so. i was thinking that this was peculiar. is something not right when my idle timing is -4?
thanks
james

is this the advancing which you all are talking about at idle? if so for me im around 5degree advance at idle if i remember right... hey james, hows it going dude? hows the tuning coming along?



Michael 99gs
HRC Stage 2
http://www.dreamwater.net/purplebeast

mine used to do the same thing at idel. Worried me the first time i noticed it. But it never seamed to affect the car in any way i could tell

That's normal. Every car i've datalogged has done that.

When i started getting a weird miss like that, it turned out to be a loose cam angle sensor. Check your cam angle, your crank angle, your plugs, coil pack, etc..

I know where the cam angle sensor is but where is the crank angle sensor. Is it behind the block?

directly above the oil filter.

I pretty much have the same problem. I have never datalogged my car; I think it has to do with the big 625cc injectors. When I lean out the "idle" fuel map to the point where the air/fuel meter will cycle back and forth, the car runs rough and wants to cut off. If I allow the air/fuel meter to stay rich at idle, then it's idling too rich.

Kon Chittavong
HRC: Stage IV | http://laoracer.homestead.com/mainpage.html

I can see some cycling of the timing advance. But going to negative numbers? And cycling like an o2 sensor? 2 weeks ago the car idled normally. All the time. Now it wants to die at a light when the timing goes negative. (I haven't changed anything either) I'm really starting to get frustrated. And it doesn't dip to negative numbers any other time while driving.