figured it out. thanks

 

Make sure your MAF's plugged in and if it is, you might have to clean your MAF
Most people put too much oil on their filters and it can cause problems. Try some CRC MAF cleaner.

 

thanks figured it out. i forgot that i loosened one of the clamps on the air bridge. tightened it seems to be fixed

 

 

It will appear again till you change it from Engine Diag. I had this problem before when I installed the P1sc kit on my ZO6. The AFR will be between 12 to 10 when this code will appear.

*3bar map sensor is the good choice for any F\I application.

 

thanks, but i don't think it will. i have ran the car for over a year with no codes. it only came on this time because i left a hose clamp loose.

 

Only if you're running enough boost to justify it. Otherwise you should run a 2-bar. Running more than you need kills your VE resolution.

 

Whats enough boost?

 

The MAF can read up to 13 psi of boost. If you are planning to go more than that you have to turn to map sensor (2 or 3 bar map sensor) coz you will zeroz the maf from your ECU.

 

I wouldn't put bigger than a 2 bar on anything running less than 16psi unless it was a turbo car.

I'm sure you don't mean to say it that way, but for the readers, the MAF can't read boost at all.

 

MAF Limitations and Speed Density

The term speed density has been used several times in the tuning section of this guide. In speed density systems, the MAP sensor and intake air temperature sensor (IAT) are polled by the PCM to calculate the air density. The PCM will then do a lookup in a pre-programmed volumetric efficiency (VE) table and get the VE for that particular RPM and MAP. The PCM can then calculate the mass air flow using VE, RPM and engine displacement.



MAF systems use a sensor that measures the air density entering the engine rather that calculating it as with a speed density system. The MAF sensor has a heated wire that maintains a constant temperature. Air flowing through the MAF sensor cools the wire requiring more current through the wire to hold the constant temperature. The amount of current flowing through the wire is proportional to the air mass flowing through the MAF sensor.



MAF systems are used on many current production vehicles. On a high boost, big horsepower turbocharged engine however, speed density is a better way to go. One reason is because MAFs and engine computers a limit to how much of air flow they can read. Tuners can get around this limit by fudging tables, but at this level it is wise to switch to a speed density system.





2 and 3 BAR MAP and Speed Density

The MAP sensor on most stock engines is a 1 bar MAP sensor. The atmospheric pressure at standard sea level is 1.013 bar, therefore, it cannot sense pressures above atmospheric. In other words, it cannot sense boost pressure. A 2 bar MAP sensor will sense up to about 14.5 psig, and a 3 bar MAP will sense about 29 psig. Remember that 1 bar is atmospheric pressure or 0 psig.



When tuning for speed density, you will need to replace your stock MAP sensor with either a 2 or 3 bar MAP sensor, depending on how much boost you want to run. 2 and 3 bar MAP sensors can be purchased from Summit Racing and other speed shops. Tuning for 2 and 3 bar speed density can be done with HPTuners, EFI Live, Bigstuff3, FAST XFI, Accel DFI among others.