Gremo87
Proven Member
- 128
- 2
- Mar 14, 2013
-
Decatur,
Illinois
Been chasing a low vacuum/low power/hard cold start/cylinder 2 lean/etc issue.
(see here if interested in backstory: http://www.dsmtuners.com/threads/my...new-perspective-still-troubleshooting.495724/)
I checked base timing and it's at 5* a lot of the time, but jumps (a lot) just past the TDC (1 T) mark. I'd say 55-60% 5* and 40-45% about 1/8"-1/4" past the 1 T mark.
What could cause this?
Could this be causing my issue, or vice versa - could the issue be causing the jumping?
If it's causing the issue, what are some things that could cause the base idle to be so unstable?
(I'm doing my own searching but wanted to get something going on here in the meantime)
Also - once the timing pin is grounded, idle surge begins and gets progressively worse the longer the pin is grounded. So if I understand correctly, that means there would always be an idle surge if the ECU wasn't constantly adjusting timing at idle to compensate and keep it from surging. (and I can't get the idle any lower than 800-850 even with the BISS bottomed out, so there's something going on with too much air getting in, and it seems to be focused at cylinder 2 as evidenced by white spark plug.)
(see here if interested in backstory: http://www.dsmtuners.com/threads/my...new-perspective-still-troubleshooting.495724/)
I checked base timing and it's at 5* a lot of the time, but jumps (a lot) just past the TDC (1 T) mark. I'd say 55-60% 5* and 40-45% about 1/8"-1/4" past the 1 T mark.
What could cause this?
Could this be causing my issue, or vice versa - could the issue be causing the jumping?
If it's causing the issue, what are some things that could cause the base idle to be so unstable?
(I'm doing my own searching but wanted to get something going on here in the meantime)
Also - once the timing pin is grounded, idle surge begins and gets progressively worse the longer the pin is grounded. So if I understand correctly, that means there would always be an idle surge if the ECU wasn't constantly adjusting timing at idle to compensate and keep it from surging. (and I can't get the idle any lower than 800-850 even with the BISS bottomed out, so there's something going on with too much air getting in, and it seems to be focused at cylinder 2 as evidenced by white spark plug.)
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