new maf and translator, rich at idle or is it?
- Thread starter Scarab
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A BLM at 125 is not bad, the ECU is pulling alittle fuel to hit it's target.
If all your other settings like Fuel Pressure are good I would say drive it.
How do the BLM's look beyond the idle cell? Are you looking at BLM's on a scanmaster or Powerlogger? I like to see all the cells in Powerlogger, gives a full picture of what the other cells beyond idle are doing.
Also, depending on which chip you have and your environmental temperature, a swing of +/-3 on the BLM's is normal for me to see on my cars. I see anywhere from 126-131 depending on if I am driving the car in 100 degree summer temps or 30 degree temps.
If all your other settings like Fuel Pressure are good I would say drive it.
How do the BLM's look beyond the idle cell? Are you looking at BLM's on a scanmaster or Powerlogger? I like to see all the cells in Powerlogger, gives a full picture of what the other cells beyond idle are doing.
Also, depending on which chip you have and your environmental temperature, a swing of +/-3 on the BLM's is normal for me to see on my cars. I see anywhere from 126-131 depending on if I am driving the car in 100 degree summer temps or 30 degree temps.
1KWIKSIX
Well-Known Member
- Joined
- Sep 29, 2007
- Messages
- 3,249
BLM’s are fine 
Almost dead nuts on , remember 128 +/- 10 is within the acceptable window . At
125 , your ECM is pulling just a hair of fuel (so yes , engine is a tiny bit rich), but nothing to worry about .
What’s your AFR at WOT at the top of 3rd gear?
Almost dead nuts on , remember 128 +/- 10 is within the acceptable window . At
125 , your ECM is pulling just a hair of fuel (so yes , engine is a tiny bit rich), but nothing to worry about .
What’s your AFR at WOT at the top of 3rd gear?
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- Feb 14, 2002
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- 5,833
I think you are looking at commanded AFR not the actual AFR? Actual AFR can only come from a wideband lamba sensor (not stock). The AFR you see on your scan tool is just a target the chip is using to do the math.
If you see the stock O2 sensor switching frequently up & down from 200mv to 800mv then you know yes you are running near stoichiometric 14.7-14.8 AFR. Probably the only chip that would try to do that would be a stock one or really old aftermarket. Pretty much anything non stock would execute a blm learn at idle and then settle into an open loop Rich idle where the O2 would stay around 700mv plus.
If you see the stock O2 sensor switching frequently up & down from 200mv to 800mv then you know yes you are running near stoichiometric 14.7-14.8 AFR. Probably the only chip that would try to do that would be a stock one or really old aftermarket. Pretty much anything non stock would execute a blm learn at idle and then settle into an open loop Rich idle where the O2 would stay around 700mv plus.
As BEATAV8 says, the only way to really get the AFR is to use a wide band O2 setup. I have an AEM X-series running to my powerlogger. I had a new O2 bung welded into my downpipe. I also have the upgraded Scanmaster that will read the wide bands AFR for me without an extra gauge on my pod.
I'm also running an older Extender chip which allows me to set an open loop idle. It idles smoother in open loop than closed loop with the stock narrow band controlling the fueling. These cars are a little complicated, but they do allow you a lot of tuning.
I'm also running an older Extender chip which allows me to set an open loop idle. It idles smoother in open loop than closed loop with the stock narrow band controlling the fueling. These cars are a little complicated, but they do allow you a lot of tuning.
