System lean does this look like a bad maf or ?

[rockchip]

I am not sure what to look for if the maf is functioning correctly or not.

Any tips?

Here is the log if anyone wants to take a look, to me the 02's(both fairly new) look good and the ect looks good.

thanks

[5FDP]

Has nothing to do with the MAF here.

Your o2 sensors go straight down under heavy throttle, that would mean it's lean per the o2 sensors. You need a wideband to really tell how lean it is.

Either the tune needs a lot of fuel added to the MAF/VE or there are other problems. Like massive vacuum leaks, low fuel pressure or bad injector data.

You're also missing lots of key data for logging.

Like knock retard, cylinder airmass, commanded AFR or Lambda, fuel trims both short term and long term, also missing injector pulse width avg for both banks. And of course a wideband oxygen sensor.

[kevin87turbot]

I am not sure what to look for if the maf is functioning correctly or not.

Any tips?

Here is the log if anyone wants to take a look, to me the 02's(both fairly new) look good and the ect looks good.

thanks

The MAF is reading up to 158 gms/sec at 5000 rpm. It may be a little on the weak side, but, before I changed anything, I would disable the 60 second PE delay that these models have, and add PE Mode and commanded AFR to the datalog. These were notorious for not going into PE mode with the OE tune.

[rockchip]

Great info thanks guys,

the wideband guage seems to read normal. I will do a new log with the wideband and more parameters logged.

[Matt Vardaman]

I am not sure what to look for if the maf is functioning correctly or not.

Any tips?

Here is the log if anyone wants to take a look, to me the 02's(both fairly new) look good and the ect looks good.

thanks

You have these codes present in that log:
Trouble Codes:
P0171 - System Too Lean (Bank 1) (Current)
P0174 - System Too Lean (Bank 2) (Current)
P0300 - Random Misfire Detected (Current)

I would start there. I have had more than one ls truck engine with intake gasket leaks that present those codes, but proper diagnosis is eveything.

[rockchip]

Great we will check the intake gaskets

[blindsquirrel]

When an O2 reads lean, it has no way to tell if the excess oxygen is coming from not enough fuel, or from a failed combustion event. If you have a misfire a whole bunch of plain ol' air and some raw fuel goes down the pipe, and oxygen sensors do not measure unburned fuel.