Help! Car running very lean!
Thread Starter
Teching In
Joined: Aug 2002
Posts: 9
Likes: 0
From: tucson, AZ
Help! Car running very lean! Got my car dynoed yesterday. I pulled pretty impressive numbers although they had to shut my car down on all 4 runs before redline because it was pinging pretty bad. Here's one of the runs where the detonation is pretty audible in the higher rpms. http://www.u.arizona.edu/~jtnelson/vids/ping.avi Also, here's a chart of my A/F ratio. These weren't the same runs but just to give you some kind of idea.
http://www.u.arizona.edu/~jtnelson/chart.jpg
I pulled the IAT module out after the dyno runs so it would richen up but I'm wondering if there's anything else I can do.
http://www.u.arizona.edu/~jtnelson/chart.jpg
I pulled the IAT module out after the dyno runs so it would richen up but I'm wondering if there's anything else I can do.
On The Tree
Joined: Dec 2002
Posts: 176
Likes: 0
From: Orlando, FL
Re: Help! Car running very lean! Couple of questions...
1) Did you open the cutout just prior to the dyno runs?
2) Do you have a completely stock MAF or has it been modified?
3) Are there any other modifications not listed?
Assuming the PCM has had time to correct the LTrims I would not expect the A/F ratio to be that lean.
Tim
1) Did you open the cutout just prior to the dyno runs?
2) Do you have a completely stock MAF or has it been modified?
3) Are there any other modifications not listed?
Assuming the PCM has had time to correct the LTrims I would not expect the A/F ratio to be that lean.
Tim
Thread Starter
Teching In
Joined: Aug 2002
Posts: 9
Likes: 0
From: tucson, AZ
Re: Help! Car running very lean! I normally drive with the cutout capped. The first three runs were done with the cutout uncapped. The last one is capped. (This is the run on the chart). My MAF is stock but descreened. Other than that, those are all my mods.
Re: Help! Car running very lean! Are saying you had one of those IAT tricker modules
on there? Fooling IAT is supposed to add spark advance,
Dunno about mixture though. Not clear on whether you
had in in place during the pulls, if so, it's a suspect
(along with way-lean mixture) in the pinging.
Kind of baffling why you look nice and fat down at 3KRPM
but go way downhill later.
on there? Fooling IAT is supposed to add spark advance,
Dunno about mixture though. Not clear on whether you
had in in place during the pulls, if so, it's a suspect
(along with way-lean mixture) in the pinging.
Kind of baffling why you look nice and fat down at 3KRPM
but go way downhill later.
