Mass aitlfow sensor

BL650 · August 2, 2005

I have a 05 GMC Z71 SLT Crewcab. A friend of mind said that if you pull the screen of the mass airflow sensor that it will give you more power, has anyone done this and does it make any difference? Thanks

BlueTahoe · August 2, 2005

I did mine and didn't notice a difference. Then I put in a 93/91 hot tune and got some spark knock. I bought a new MAF and installed it last night and that cured the pinging. On a stock tune you will probably never have a problem due to the conservative nature of the tune but I would say leave it in. That way it doesn't cause problems if you do any mods down the round.

I got all of my spark knock at partial throttle. I didn't get any at WOT. So I got the most spark knock during everyday driving. Excessive spark knock will kill an engine.

Butch 02 Denali · August 2, 2005

Glad that solved your pinging problem Casey!

FYI...The #1 cause of pinging problems is a dirty, descreened or failing mafs. It is a more common problem that you think!

Ape0r · August 2, 2005

Can you imagine any possible reason why GM would put a screen on it if, overall, it was better off without a screen?

BlueTahoe · August 2, 2005

From what I understand the screen is there the help straighten the air for a better reading across the sensor. Most opinions I have read say the screen's restriction is not what causes the increase in performance. The performance difference is due the the MAF readings changing thus the computer leans the fuel mix some. This is ok on a stock tune. When you tune it to the edge then the de-screened MAF pushes it over the edge and causes some spark knock (pinging).

I believe GM has started using MAF without a screen for some of it's performance cars but the computers or MAF are calibrated differently to account for the different air flow.

This is my understanding. I didn't notice much if any difference in performance when I descreened but I definitly had pinging at partial throttle with the HOT tune that went away with the new MAF. FYI - I had cleaned the old MAF very well to eliminate a dirty MAF causing the pinging.