So we know it wasn't causing a problem. The chip burner guesses as to the amount of fuel your motor needs at various loads and throttle openings. If his guess isn't exactly on,the computer will adjust based on what the oxygen sensor tells it. Don't concern yourself with not seeing a 128. It's not important. It could be a clue to a vacuum leak,but a low IAC number would be a much better indicator of that. It sounds like you're OK.
Idle vs. Cruise BLMs
- Thread starter mtbraun
- Start date
So we know it wasn't causing a problem. The chip burner guesses as to the amount of fuel your motor needs at various loads and throttle openings. If his guess isn't exactly on,the computer will adjust based on what the oxygen sensor tells it. Don't concern yourself with not seeing a 128. It's not important. It could be a clue to a vacuum leak,but a low IAC number would be a much better indicator of that. It sounds like you're OK.
Jerryl
Tall Unvaccinated Chinese Guy
- Joined
- Dec 14, 2004
Im my experience:
A good running car, that has the Valve Cover to turbo inlet piping removed, AND is still running PCV will see idle BLM’s in the 138-142 range.
You can reduce the deviation by increasing FP, which will affect ALL other BLM ranges.
FP setting can be off based on a non-calibrated gage and reading error.
If you have a translator, you can adjust the idle which will also make a slight difference.
Intake air temp, winter vs. summer fuel grade will also affect BLM.
While 128 is the “magic number” is not that important as stated by Ttype6.
A good running car, that has the Valve Cover to turbo inlet piping removed, AND is still running PCV will see idle BLM’s in the 138-142 range.
You can reduce the deviation by increasing FP, which will affect ALL other BLM ranges.
FP setting can be off based on a non-calibrated gage and reading error.
If you have a translator, you can adjust the idle which will also make a slight difference.
Intake air temp, winter vs. summer fuel grade will also affect BLM.
While 128 is the “magic number” is not that important as stated by Ttype6.
I've had the same car for about 12 years, and I've made many incremental changes over the years. To my recollection, the idle BLM on my car has always been a little higher than the others, especially when I put the car in park and let it run for a while. This seems to happen even on chips that I've tuned and burned myself. I'm not sure why, maybe it is the extra PCV air that comes into the engine which has a greater effect at idle than while cruising.
If all of your other BLM's are hovering around 128 and your idle BLM is higher, I wouldn't worry too much about it unless it's getting close to 150. If you checked for vacuum and exhaust leaks, then it's probably just a slight tuning mistake by the chip maker. If it bothers you, then try enabling either rich idle or open loop idle in your chip and see how it runs.
Good luck,
Mike
Sent from my HTC Droid Incredible using Turbo Buick
If all of your other BLM's are hovering around 128 and your idle BLM is higher, I wouldn't worry too much about it unless it's getting close to 150. If you checked for vacuum and exhaust leaks, then it's probably just a slight tuning mistake by the chip maker. If it bothers you, then try enabling either rich idle or open loop idle in your chip and see how it runs.
Good luck,
Mike
Sent from my HTC Droid Incredible using Turbo Buick
After many years, I finally found the fix for high idle BLM, at least on my car. Here's the thread...
http://turbobuick.com/forums/thread...e-blm-and-idle-vacuum-all-in-one-shot.381668/
Hope this helps...
http://turbobuick.com/forums/thread...e-blm-and-idle-vacuum-all-in-one-shot.381668/
Hope this helps...
