could a bad MAF cause the truck to run lean & ping? pulled the plugs yesterday, and they are burnt quite badly they have never been this white before......its weird, when i turn the a/c on, the truck has a random misfire, hesitates, pings, and it lugs like i am pulling a trailer......turn the ac off and it runs fine except for the pinging under a load @ low rpms. the truck is a stock 2000 5.3L with l/t's ory and a granatelli MAF. ( the maf was free...i wouldnt buy one)

 

Yes, a bad or miscalibrated MAF could easily cause that. I'd pull the granatelli and re-install the stock on ASAP

 

It Stumped Me Because It Only Runs Like That With The Ac On...... I Am Tryin To Get A Stock Maf As We Speak..... Any Other Ideas

 

Dude, ditch the Granatelli MAF sensor! I bought one and over a 4 month period of time it F@#ked up my truck so bad. They are Total BS. The stock one is good for like 500 HP. You can get a remanufactured OEM sensor from AutoZone for like $75.00 with a 1 year warranty. I bet you'll be amazed how dramatic of an improvement it will be (I was). Good Luck! -Parker

 

update.....i put a oem MAF on the truck today and it helped dramatically. it doesnt act like it is lugging or struggling to go, but it still has a lil bit of hesitation & random misfire with the ac on. i dunno....any more info would be great. thanks

 

Anyone?

 

ttttttt......

 

What are your Mods done?

 

Are you sure its a misfire or is it just a bumpy idle, cause that is not all that uncommon for these trucks. I have my idle tuned to a T and its still not the smoothest in the world, and thats with the smooth idle of a LS6 cam. When was the last time the plugs or wires were changed? Fuel filter dirty?

Chris

 

No Its Not The Idle....driving @ 2000-3000 Rpms It Has A Random Misfire With The Ac On...i Can Hear It Drop A Cylinder For A Split Second. Turn The Ac Off, And It Goes Away Instantly. The Truck Is Bone Stock With Longtubes & Ory & A K&n Filter