P0102 code, but no maf
12-05-2015, 07:06 PM
#1
Safety Car
Thread Starter
P0102 code, but no maf
[P0102 Code] Hey, I have a 2000 C5 FRC with a TTiX twin turbo kit. There is no maf installed with this setup and I have never had a code.
A week or two ago I installed a MSD 2 step and one night while playing around with it on the street I saw a P0102 (maf low voltage) code pop up and the car started to run a little funny once in a while. It also tripped both 02 sensor codes for the heater elements but I replaced both 02 sensors and spark plugs and those went away. But not the maf code. What do yall think it could be? I have a 2.5 bar map sensor on the back of the intake. Could something have happened to that or is that a separate code?
The car also runs richer at wot and high rpms. Used to be around 10.9-11.1 but now it's like 10.1. It also threatens to stumble or stall once in a while.
A week or two ago I installed a MSD 2 step and one night while playing around with it on the street I saw a P0102 (maf low voltage) code pop up and the car started to run a little funny once in a while. It also tripped both 02 sensor codes for the heater elements but I replaced both 02 sensors and spark plugs and those went away. But not the maf code. What do yall think it could be? I have a 2.5 bar map sensor on the back of the intake. Could something have happened to that or is that a separate code?
The car also runs richer at wot and high rpms. Used to be around 10.9-11.1 but now it's like 10.1. It also threatens to stumble or stall once in a while.
12-06-2015, 11:58 AM
#2
Safety Car
MAF fault processing enablers need to remain on or else the car won't fail over to MAP only. You can disable the MIL for these, but the actual faults still need to run their course.
12-07-2015, 09:14 PM
#3
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St. Jude Donor '13-'14-'15
Just sounds like your tuner forgot to set ALL the MAF codes to read "not reported" and "no mill" Most just delete P0101 and forget P0102 and P0103
ALSO did you get an actual check engine light ? or did you read the codes with tuning data logger ?
Most data loggers will still show codes even if they are deleted but NO check engine light will come on----They are identified by a YELLOW color---A real code would have a RED color if not deleted plus show a check engine light
ALSO did you get an actual check engine light ? or did you read the codes with tuning data logger ?
Most data loggers will still show codes even if they are deleted but NO check engine light will come on----They are identified by a YELLOW color---A real code would have a RED color if not deleted plus show a check engine light
12-07-2015, 09:21 PM
#4
Safety Car
Thread Starter
No, the tuner turned them off. The car had no codes whatsoever until I used the 2 step while rolling at 45mph one night. It's usually a yellow but sometimes becomes a red code, with check engine light. A/F gauge seems to read normal though.
The reason I'm worried is that it wasn't there until after the 2 step, and now the car runs a little rougher at lower rpms than before, sometimes with some hesitation. Also threatens to die at times when still cold.
The reason I'm worried is that it wasn't there until after the 2 step, and now the car runs a little rougher at lower rpms than before, sometimes with some hesitation. Also threatens to die at times when still cold.
12-08-2015, 11:16 AM
#5
Safety Car
You can't not allow the MAF to report a failure or else the car won't run at all. Odd that you never got a MIL before and you have now though, have you spoken to your tuner on the matter? That would have been the first thing I did. Also, is the weather cooler now than before? I had a car with a standalone that would run richer under boost in cooler weather despite the IAT maps being "ideal".
12-13-2015, 11:47 PM
#6
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St. Jude Donor '13-'14-'15
Most 2 steps I have used will control RPM's when asked to and then when a Lower RPM is not needed like at launch the 2 step switches to the Hi RPM safety limiter
If you suspect the installation of the 2 step is when your problems started then it's when the box is trying to control the RPM's at the lower set point--MSD controls the lower set point by randomly shutting off the ignition to cylinders therefore limiting the RPM's---Seems like the ECM is "false triggering your codes---I would guess that while the 2 step is limiting launch RPM's the ECM records an incorrect airflow value thru the MAF--
In EFILIVE there is a table called " predicted airflow" in the diagnostics section---I would think you would need an adjustment to this table to eliminate the false trigger of your MAF codes due to the 2 step--
If you suspect the installation of the 2 step is when your problems started then it's when the box is trying to control the RPM's at the lower set point--MSD controls the lower set point by randomly shutting off the ignition to cylinders therefore limiting the RPM's---Seems like the ECM is "false triggering your codes---I would guess that while the 2 step is limiting launch RPM's the ECM records an incorrect airflow value thru the MAF--
In EFILIVE there is a table called " predicted airflow" in the diagnostics section---I would think you would need an adjustment to this table to eliminate the false trigger of your MAF codes due to the 2 step--