Multiple Codes seem to be connected need help

[BlueCollarTahoe]

2004 chevy tahoe LT 5.3 v8

got a code reader after engine light came on solid. Pulled codes P0442, PO300, PO171, P0131. Thought maybe it was the spark plugs, mechanice pulled and replaced with AC Delco iridiums. Said the plugs were still good, the wires were shot. changed them. Light on still and have the PO300 and PO171 and PO131. Suggested i change the Coils once i get them which i will do, but im worried about the Lean Bank code. watched some videos, read some articles, could be a myriad of things. anyone have any suggestions how i should go about fixing this stuff? i can change filters, possibly the sensors after cleaning them etc on my own. any advice? ideas? thanks.

 

[01ssreda4]

Clean MAF and replace both o2 sensors and I bet your issues go away.

 

[BlueCollarTahoe]

gonna clean the MAF tomorrow. think replacing 02 sensors is easy enough for a newbie? Im a handyman otherwise just not on cars lol

 

[BlueCollarTahoe]

also do you need just 2? seen some reviews people talking as if they used more. was gonna go with this one:

ACDelco 213-1702 GM Original Equipment Heated Oxygen Sensor

i think this is the right one

 

[06Escalade]

I'm thinking vacuum. The intake manifold gasket is cheap and easy to replace. I would replace the throttle body gasket as well while its apart. also, are you consuming any oil?

 

[BlueCollarTahoe]

oil seems fine. put it in the week after i got it, slowly winding down. couple months at 55 percent now. this is what i did today:

I cleaned the throttle, was dirty.

I cleaned the MAF, was filthy.

Changed the air filter. used a FRAM equivalent couldnt find an AC Delco anywhere.

reset the codes, started the car up, no return yet. feels stronger. still had a rough idle. Should I change the 02 sensors anyway? which ones are the correct ones for 2004 chevy tahoe 5.3 v8?

 

[BlueCollarTahoe]

ugh, light came back on. p0300. had the spark plugs and wires changed on friday before i did the above. the rest of the codes did not come back though. any thoughts? looking at the ignition coils next

 

[01ssreda4]

Drive it around and see if it will give you a specific cylinder number for a misfire.

 

[BlueCollarTahoe]

Drive it around and see if it will give you a specific cylinder number for a misfire.

thats basically what i came here to post. I drove it maybe 25 miles today. i pulled with my reader got 0300, and the 171. I went to an autozone to see if they pull with a better reader if ittl tell me which cylinder. they got the same codes, random misfires, but their computer said i should replace the fuel pressure regulator. Havent seen this in any diagnostic lists. where is it on a 2004 chevy tahoe? seen videos of suburbans same years and its not in the same place. anyone whos gone through this what should i replace next? i can only do one at a time. the coils, the sensors or now this fuel pressure regulator? any thoughts?

 

[01ssreda4]

I wouldnt replace the regulator unless it tests bad.