Big Time Advice - Immediate Drop to 7.4 AFR
#1
Super Member
Thread Starter
Big Time Advice - Immediate Drop to 7.4 AFR
Fellas,
Ah, so I don't think this is too good. Data logging started TODAY as got my bung welded in today and O2 sensor operational...
When I drop the hammer (any gear any speed any circumstance) the AIT immediately drops from 14 to 7.4.
IAT's go from ambient (79 degrees) to as high as 143 on a 40-80 pull.
My recent visit to the dyno shop the AFR started at 14 with a gradual decrease to 11 at 6,300 RPM.
3,000 RPM - 13.7
4,000 RPM - 12.7
5,000 RPM - 11.8
6,000 RPM - 10.9
NOT SURE WHAT IS UP with the immediate drop to 7.4 (more accurate reading).
I "thought" I logged my run but the memory card isn't readable by the LM-2 (its an old memory card and the LM-2 device requires a 4GB or smaller SD card.
At any rate. Advice please if I should park the car (or drive it real easy) given the data logger results.
TK
Ah, so I don't think this is too good. Data logging started TODAY as got my bung welded in today and O2 sensor operational...
When I drop the hammer (any gear any speed any circumstance) the AIT immediately drops from 14 to 7.4.
IAT's go from ambient (79 degrees) to as high as 143 on a 40-80 pull.
My recent visit to the dyno shop the AFR started at 14 with a gradual decrease to 11 at 6,300 RPM.
3,000 RPM - 13.7
4,000 RPM - 12.7
5,000 RPM - 11.8
6,000 RPM - 10.9
NOT SURE WHAT IS UP with the immediate drop to 7.4 (more accurate reading).
I "thought" I logged my run but the memory card isn't readable by the LM-2 (its an old memory card and the LM-2 device requires a 4GB or smaller SD card.
At any rate. Advice please if I should park the car (or drive it real easy) given the data logger results.
TK
The following users liked this post:
BlackHammer (09-09-2016)
The following users liked this post:
BlackHammer (09-09-2016)
#4
Super Member
You have the bung in the proper place and did you calibrate the sensor?
7's AF reading is crazy rich, which tells me it's not a true reading. Your car would stumble like a m'fer if that was a true reading.
7's AF reading is crazy rich, which tells me it's not a true reading. Your car would stumble like a m'fer if that was a true reading.
The following 2 users liked this post by Mike450:
BlackHammer (09-09-2016),
Hulk (09-09-2016)
#5
Super Member
Thread Starter
I MAY have found one of the reasons for the 7.4 AFR. I am trying to get the right firmware for the Logworks application and handheld device.
Am I on to something?
The instructions in this section eventually read "Note: Performing a firmware upgrade to the LM-2 clears all calibration data. Perform a sensor calibration on the next power up after a firmwareupgrade. Be sure to have the O2 sensor OUTSIDE OF THE EXHUAST (free air.)".
Well, the exhaust shop installed the sensor and ran it into the car. After installation I did the calibration (which matches the guidelines in the manual for all it matters) WITH the sensor IN the bung. After locating a video on the install I am thinking this might be the culprit.
Nothing seems to be coming easy for me on this! Life could be worse I suppose!
#6
Member
This sounds like you need it calibrated. I am willing to bet 7.4 is the bottom of the scale. Usually when I have had widebands fail they go right.
If you want to test use a propane torch that is not lit and with the sensor in open air hit it with propane. You should see it go from high lean to high rich.
If it sweeps you may have an install issue. If not, either sensor or calibration.
If you want to test use a propane torch that is not lit and with the sensor in open air hit it with propane. You should see it go from high lean to high rich.
If it sweeps you may have an install issue. If not, either sensor or calibration.
The following users liked this post:
BlackHammer (09-09-2016)
#7
Super Member
Thread Starter
This sounds like you need it calibrated. I am willing to bet 7.4 is the bottom of the scale. Usually when I have had widebands fail they go right.
If you want to test use a propane torch that is not lit and with the sensor in open air hit it with propane. You should see it go from high lean to high rich.
If it sweeps you may have an install issue. If not, either sensor or calibration.
If you want to test use a propane torch that is not lit and with the sensor in open air hit it with propane. You should see it go from high lean to high rich.
If it sweeps you may have an install issue. If not, either sensor or calibration.
What spooked me was the car did seem to stumble the top of 2nd gear as described (it has never done that before) and had a "hot engine smell" when I parked it shortly after the 20-50 mph pull.
I am removing the 77mm fixed and going back to the 84mm clutched just to make sure I am not going to grenade the motor. Plus, I only got another 10 RWHP out of the 77 fixed so not worth the risk with the additional heat.
Can't wait for certain folks (ceterline) to come out of the woodwork and give me a (aka "told ya so on the 77 being too much with the 168 combo.
77 fixed s/c pulley for sale. $100 including shipping!
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#8
Member
Don't tempt me! What would a 77 FSP do with an otherwise stock E55?
As for your O2 I can guarantee you are not running that rich. Your car would not run as said previously.
I am sure this is simply a scaling issue. Really the thing that kills O2 sensors is water and leaded fuel.
Take your time, follow the directions, and you will be right where you need to be.
You got this.
As for your O2 I can guarantee you are not running that rich. Your car would not run as said previously.
I am sure this is simply a scaling issue. Really the thing that kills O2 sensors is water and leaded fuel.
Take your time, follow the directions, and you will be right where you need to be.
You got this.
#9
Member
Mine also goes full rich on say 1/2 - 7/8 throttle. This i can see on my wide band AFR, and also the black cloud behind the car.
On the dyno it also did this, but when i went FULL throttle, ( the bit you feel on the pedal, like it hits a switch ) it went back to 12's
I never go full throttle on the streets, as mine isn't stock and it is usually wheel spin.
It didn't used to do this, but I think slowly got worse.
It is making about 500rwhp.
May have to look at the tune, but also thinking if any sensors are bad.
On the dyno it also did this, but when i went FULL throttle, ( the bit you feel on the pedal, like it hits a switch ) it went back to 12's
I never go full throttle on the streets, as mine isn't stock and it is usually wheel spin.
It didn't used to do this, but I think slowly got worse.
It is making about 500rwhp.
May have to look at the tune, but also thinking if any sensors are bad.