Mean Green Z28
June 12th, 2014, 03:54 AM
A bit of background...
Issue:
Bought the car (2010 Camaro LS3) late last year, and noticed a stumble at times; mostly in traffic/idling. Car as far as I know was stock except for a catback. No signs of any work being done/reversed in the engine bay. Installed the "strong" MAF as they call it as I had the bad one, it didn't help. Also was able to get a cold air kit (by CAI) and installed that.
Through the winter, everything was fine, as the outside temps got colder. As the weather got warmer, I noticed the stumbling again and it got worst.
What we've done for now:
Got a EFILive license using a friend's shop and he adjusted the MAF table a down a bit in the lower ranges to keep the car from stumbling. This helped, but car feels slightly sluggish from a start as if it's trying to catch up; then is fine at the top end ... although we have noticed some knock retard (3-4 deg) at the top end too. This is without using the A/C.
More/present:
I'm still fine when I don't use A/C. When I turn the A/C on, I notice the engine pick up a bit to offset the load. However, when I turn it off; or when the clutch disengages during normal operation, it stumbles and starts right back up again. I'm really at my wits end with this car. I love almost everything about it ... almost!
Question:
Could it be a BCM issue? Tuning issue? There's two A/C tables (b1825/6) that were mentioned to me, which one do we look at? I'm still a nOOb at this ... give me ladder logic and machinery design and control and I'll do it, but I'm still trying to wrap my head around ECM's.
Internals are stock (afaik) with only an intake and catback. It's my daily driver too.
vid I took yesterday ... http://youtu.be/0DpGOJR-fp8
Issue:
Bought the car (2010 Camaro LS3) late last year, and noticed a stumble at times; mostly in traffic/idling. Car as far as I know was stock except for a catback. No signs of any work being done/reversed in the engine bay. Installed the "strong" MAF as they call it as I had the bad one, it didn't help. Also was able to get a cold air kit (by CAI) and installed that.
Through the winter, everything was fine, as the outside temps got colder. As the weather got warmer, I noticed the stumbling again and it got worst.
What we've done for now:
Got a EFILive license using a friend's shop and he adjusted the MAF table a down a bit in the lower ranges to keep the car from stumbling. This helped, but car feels slightly sluggish from a start as if it's trying to catch up; then is fine at the top end ... although we have noticed some knock retard (3-4 deg) at the top end too. This is without using the A/C.
More/present:
I'm still fine when I don't use A/C. When I turn the A/C on, I notice the engine pick up a bit to offset the load. However, when I turn it off; or when the clutch disengages during normal operation, it stumbles and starts right back up again. I'm really at my wits end with this car. I love almost everything about it ... almost!
Question:
Could it be a BCM issue? Tuning issue? There's two A/C tables (b1825/6) that were mentioned to me, which one do we look at? I'm still a nOOb at this ... give me ladder logic and machinery design and control and I'll do it, but I'm still trying to wrap my head around ECM's.
Internals are stock (afaik) with only an intake and catback. It's my daily driver too.
vid I took yesterday ... http://youtu.be/0DpGOJR-fp8