Cleaned my MAF sensor for the first time today, and noticed that mine isn't stock. It says <PBT GF40>, it's about 94mm long, and looks like this: http://www.hitachi-automotive.us/htm...n-type-MAF.jpg

The first owner installed a K&N intake and the sensor, and I'm pretty sure he never tuned it. Should I get a tune? How strongly would you recommend tuning it? That's quite an expense...

Thanks.

 

Well unless that MAF is calibrated to function exactly as the stock unit, you will likely either run lean or rich depending on how its calibrated. A tune would re-calibrate it, however since you dont seem to want to go that route, possibly go with a stock MAF to replace that one.

 

If I replace it with a stock one, and he actually did tune the truck, I risk throwing things off. I'll try to get it tuned, thanks.

 

Does changing the MAF do anything for these trucks? Years ago it was the whole housing, some of those did flow better but these trucks it's just the sensor itself.

 

Are you having issues with it?
If the truck is running fine, then leave it alone.

 

Hell if I know... throttle response feels weak, and I think this might be why.

 

Ahh, I see. Unfortunately, that's a part that's too expensive to replace when you don't even know if it's giving you issues. I think I would explore other options first, like cleaning the throttle body, checking your plugs, check your O2 sensors (if you can).
I would imagine the guy who sold it would mention putting a tune on it.
If you haven't yet, clean the throttle body also, and disconnect the battery while you at it to clear the pcm. The pcm adjusts itself to certain conditions. Sometimes it can be helpful to clear that out and start over. That won't delete any tune you may (or may not) have, so don't worry about anything messing up.

 

when your done with What Lew suggested do the Diamond bird fix for you throttle..

 

If you have a friend with a tuner like an SCT, ask them to borrow it for data logging. Log your MAF and your Short Term Fuel Trims. The fuel trims should be around 1.0 in closed loop. Also look at the Long term fuel trims. They should also be trending around 1.0. If things are more than .05 + or - then chances may be that the MAF is not accounted for in the "tune".