need help solving lean condition

[Scottydoggs]

im just going back to work, good old winter layoff, so sundays would be best.

 

[muncie21]

When you first start your motor, the PCM is in open loop mode, meaning LTFT/STFT are locked. Fueling is done via the MAF and VE tables in the PCM. Only when you hit operating temps do the fuel trims unlock and adjust according to your O2 value.

If you are getting bad gas mileage + your PCM thinks you are running lean, sounds like outside air is hitting your O2s. This will make your PCM think you're running lean, which compensates by adding more fuel (positive fuel trims). In reality, you're running rich because the additional oxygen isn't from the combustion process, it is outside air leaking in.

I would pull the plugs to see if they show lean or rich condition and troubleshoot from there.

 

[HACK BLOCK]

here's the pictures of the passenger side plugs. #8 plug was loose

 

[HACK BLOCK]

here's the pictures of the passenger side plugs. #8 plug was loose

 

[Scottydoggs]

yup, those look like its running lean.

see any missing manifold bolts? the back one likes to break off or just come loose and fall out. had both happen in the past.

the hoe i just got has that back pass side bolt broke or missing. ill fix that when i install my headers.

 

[HACK BLOCK]

I think I noticed 2 missing on the passenger side I wasn't sure

 

[BlueCollarTahoe]

so to check for proper numbers you need to record the ltft1 and ltft2 while driving?

 

[Scottydoggs]

scan bank one and two

 

[shoplizard]

Just out of curiosity, how does the vehicle run on the highway at WOT? What is the MAF reading and what are the LTFT readings on each bank at WOT (wide open throttle).Your MAF should be around 200 GPM (give or take 20). and both LTFT's should be near 0. If the MAF readings are very low and the LTFT's are high I would suspect you have a faulty MAF sensor, some do not respond to cleaning. Leaking intake gaskets show only a minor fault at high RPM usually imperceptible. Also, monitor your fuel pressure while driving at WOT, this may be tricky, so be careful and use good equipment, this could tell you a lot. If the fuel pressure drops below minimum specs, it could indicate a faulty fuel pump and/or a plugged filter. Some of the filters are part of the fuel pump assembly (2005 and up). Good luck.

 

[BlueCollarTahoe]

okay im getting the same MPG as Hackblock as we seen in another thread. now i want to get the recordings down right as theyre doing in here. what exactly at im looking for?

idle:
RPM
MAF
LTFT1
STFT1
LTF1
LTFt2


and when yall say under pressure what does that mean? driving on thje highway at 65 mph? up to operating temp? all the [particulars i listed above is whats needed to compare?