Issue with mpg, power and low humming noise

[pk64f100]

My 2001 tahoe 4x4 5.3 has lost a little power, loss of gas milage and it is a little loud kinda like a exhaust leak but can not find one. It is a hum and when i let off gas it has a little popping sound very slight nnot too loud but definitely something is wrong. I have good oil pressure and runs ok but definitely not as good and it has 180,000 miles. Anyone have any ideas (ignition, fuel or???) thanks!

 

[OR VietVet]

My 2001 tahoe 4x4 5.3 has lost a little power, loss of gas milage and it is a little loud kinda like a exhaust leak but can not find one. It is a hum and when i let off gas it has a little popping sound very slight nnot too loud but definitely something is wrong. I have good oil pressure and runs ok but definitely not as good and it has 180,000 miles. Anyone have any ideas (ignition, fuel or???) thanks!

Need fuel pressure test results and check for cats clogged. Get MAF cleaner at parts store and clean the MAF.

 

[pk64f100]

is cleaning MAF EASY TO DO?

---------- Post added at 06:34 PM ---------- Previous post was at 06:33 PM ----------

Also is it possible to ream out the cat? or do i have to replace?

 

[OR VietVet]

Cleaning MAF is easy. Follow the directions on the can. You don't ream out cats, you replace them. Also, need the fuel pressure readings. Also, while you are cleaning, get carb cleaner and clean the throttle bore of throttle body. If you need to just look at you tube for the steps of doing all that I have laid out here.

 

[pk64f100]

Thanks for the help.