Yeah that is pretty low, depending on what PID your using you are basically just returning the value in the table.. I doubt that is a direct reading... Since you are lean in boost sounds like you just need to up the MAF table alot.... Can you post a log?

 

Yup....the first log is before I cleaned the MAF, and it was about a 40min drive in all types of conditions, stop, start, etc so it's a good data representation.

The second log is after I cleaned the MAF and only took it out for 5min or so just to see if the mass air flow was any different. Since both readings were the same i don't think cleaning the MAF did anything.

I should also note that the first log it was reading in lb/min, but the second is in g/s, but I don't remember changing anything between the two. Either way they are the same (225g/s = 30lb/min)

 

after looking at your logs, I don't think anything is wrong with your MAF... You just need the tune updated... It appears the MAF table is not calibrated for you setup... Just should be able to address it when he retunes... BTW, why did you think something was wrong with your MAF?


Also select GM.MAFFREQ not GM.MAFFREQ2...

 

Because I sent the first log (the bigger file) to Justin@blackbear, and he said

"High 14s while cruising is expected, that is closed loop operation for you.

Otherwise, can you clean your MAF sensor? With all inputs reading properly into the PCM, it should be significantly richer than that. The MAF is reading much, much lower than expected for boost, especially with a 5.3L. At it's peak point in this log file, the MAF is reading less airflow than a stock 5.3L would."

Like I said, I'm totally green to tuning, and i'm just going by who most seem to regard as one of the best in the business at tuning.

I opted to use the FlashScan V1 tuning option, so he sent me the baseline tune, and I logged the data for him to tweak, and he doesn't seem to think the MAF is reading properly, so......I'm not really sure what to do at this point. I already emailed him the same as what I've posted here, awaiting response.

 

Have you thought about goin Open Loop Speed Density 2 Bar
For me it was much much easier to tune than playing with the MAF.

I had the same problems years ago when i was learning how to tune and justin suggested to just go speed density. I did and im still running it today 6 years later.

 

I wonder if it is the placement of the maf. You say it is attached dorectly to the TB. Do you have a bend directly in front of it? If so that bend is not allowing the air to pass across the sensor correctly.

 

No, I haven't, because I don't even know what that is

However work is slow today, and I will do some reading/research.

 

Ya there is an elbow/4"-2.5" reducer right in front of it. I've seen numerous MAF's in this configuration on other's turbo trucks, but then again it seems to work for most, yet some have problems.

 

Yea either get the MAF in a straight run with several inches of no bends before it.

Or get rid of it and do speed densisty.

 

or possibly roatating the maf and see if the readings change?