Running rich...not sure why?
Running lean...not sure why? Hi all -
I have a basically stock '02 TA, 26500 miles on it. Just has lid, and cut out. I had it dyno'd today and the A/F was showing to be really rich until around 3500 RPM's. Which sounds about right, because I get a gassy smell when driving around town around those RPM's. I don't have the smog equipment hooked up, would that cause anything? I'm on stock plugs/wires. I also did de-screened the MAF, but I was having the same problem before that.
Any ideas? It dyno'd pretty good, but was definitely lean up to those RPM's.
Thanks,
Grant
I have a basically stock '02 TA, 26500 miles on it. Just has lid, and cut out. I had it dyno'd today and the A/F was showing to be really rich until around 3500 RPM's. Which sounds about right, because I get a gassy smell when driving around town around those RPM's. I don't have the smog equipment hooked up, would that cause anything? I'm on stock plugs/wires. I also did de-screened the MAF, but I was having the same problem before that.
Any ideas? It dyno'd pretty good, but was definitely lean up to those RPM's.
Thanks,
Grant
Last edited by DFWGrant; Aug 29, 2007 at 05:51 PM.
Anyone? I know something isn't right, because when looking at my '99 z28 that had the same mods, except the de-screened/ported MAF, with 30k miles on it, didn't do it. Here's the dyno from the '99 z28. I'll circle where I'm having problems with my '02 TA.
don't know what graph you are looking at, but the one you posted looks like it has nice consistent AFR from 12.6/7-13.0:1... nearly exactly where it should be if that wideband is right
If you click on it, in red I graphed where my '02 is way high (15.1) all the way up to 3600 RPM, the rest of the graph is the way both my '02 and '99 looked. I'm talking about the red, where I highlighted the 15.1 A/F, up to 3600 RPM's where it then comes down to 13.1
15.1 is a lean condition.
If yall started the pull at 3600 RPM's then where it dropped down to 13 is a good spot for it to be.
Just cruising around the AFR is going to raise and fall as the car adjusts its self for normal driving.
If yall started the pull at 3600 RPM's then where it dropped down to 13 is a good spot for it to be.
Just cruising around the AFR is going to raise and fall as the car adjusts its self for normal driving.
Do you think it could of been caused by me de-screening and porting the MAF?
Also, the black represents my 99 z28 from about 1.x years ago, but with very similar mods, except the ported/de-screened MAF.
I dyno'd at the same place with my '02, that I did with my 99. My graph for my '02 is almost exactly the same as my '99, except in the red part. From around 3000-3200, even lower - I was right at 15:1, where as my 99 z28 never went that high in that area.
Could it be the plugs/wires?
Ported/de-screened MAF?
Any ideas?
Thanks.
Also, the black represents my 99 z28 from about 1.x years ago, but with very similar mods, except the ported/de-screened MAF.
I dyno'd at the same place with my '02, that I did with my 99. My graph for my '02 is almost exactly the same as my '99, except in the red part. From around 3000-3200, even lower - I was right at 15:1, where as my 99 z28 never went that high in that area.
Could it be the plugs/wires?
Ported/de-screened MAF?
Any ideas?
Thanks.
