Bank 1,2 lean

[cermakf2017]

Looking for ideas on bank 1&2 lean, 2001 yukon 5.3 2wd.
New maf, had issue with egr but cleaned it, been having random misfire also

 

[Miami-Dade]

@cermakf2017 Moved your here from Site News.
Welcome from NYC&Miami!

 

[justirv]

Looking for ideas on bank 1&2 lean, 2001 yukon 5.3 2wd.
New maf, had issue with egr but cleaned it, been having random misfire also

If you haven't changed out your intake manifold gaskets, those are suspect. They shrink and can be more noticeable when cold. Also exhaust leaks from broken exhaust manifold bolt(s) are common.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

 

[Fless]

In addition to the previous suggestions:

Any unsealed ports or cracks in the intake tube between the MAF and the throttle body? Is the tube well sealed at the throttle body?

What does the MAF report at hot idle, in g/sec (not lb/min, please)?

Any exhaust manifold leaks?

What are the short- and long-term fuel trims, both at hot idle and at 1800 rpm or so? (8 values; 4 for each bank)

What is the fuel pressure at the passenger rail?

What is the fuel pressure with KOEO (key on, engine off), before starting?

Has a CASE relearn been done to sync the crank sensor to the cam position? Have either of those sensors been replaced without doing the CASE relearn?

 

[Walkercraig01]

I just went through this .. clean the throttle body really good .. unplug it then replug in .. also check your intske
Manifold gaskets .. mine was the throttle body . But it could be a number of things

 

[cermakf2017]

If you haven't changed out your intake manifold gaskets, those are suspect. They shrink and can be more noticeable when cold. Also exhaust leaks from broken exhaust manifold bolt(s) are common.

Sor took so long to respond. I didn't do the intake gasket but I did buy them along with egr gaskets. I'm planning on found them this weekend

 

[cermakf2017]

Sor took so long to respond. I didn't do the intake gasket but I did buy them along with egr gaskets. I'm planning on found them this weekend

Update: so I did the intake manifold gasket and injectors, along with egr valve gasket and whatever other gaskets came in the kit! Now i get a p0446 code for "Exhaust Gas Recirculation (EGR) Sensor A Circuit Low"...

 

[Fless]

That's an EVAP code. Are you sure that's the right code you read?

P0446 — 2001 GMC C 1500 Yukon 2WD V8-5.3L VIN T Service Manual | Operation CHARM

Detailed repair manual for the 2001 GMC C 1500 Yukon 2WD V8-5.3L VIN T.

charm.li

By your description it might be a P0405?:

P0405 — 2001 GMC C 1500 Yukon 2WD V8-5.3L VIN T Service Manual | Operation CHARM

Detailed repair manual for the 2001 GMC C 1500 Yukon 2WD V8-5.3L VIN T.

charm.li

 

[Fless]

Continued in a new link:

Egr pissing me off!

So I did the intake manifold gasket and injectors, along with egr valve gasket and whatever other gaskets came in the kit! Now i get a p0405 code for "Exhaust Gas Recirculation (EGR) Sensor A Circuit Low" I've taken it back off and cleaned it, it went away then came back with a p0404 "EGR CKT...

www.tahoeyukonforum.com

 

[cermakf2017]

I am getting the p0404, p0405 code now. That's a new thread I just posted