jQuery not supported.



Lean Codes

P0171 P0174 codes

Lean Codes

Postby red_chaser [OP] » Jan 19 2012, 6:38am

Hello. I'm a newbe here.

I first had a check engine light for some knock sensors. I went and replaced those, took off the intake manifold, replaced the seals, cleaned my injectors, and put everything back. Torqued down the manifold screws to 44 in-lbs then 89 in-lbs, put all the hoses back, cleaned the throttle body, and re-installed the EGR hose.

The Knock sensor codes cleared and about a day later got new codes, P0171 & P0174. Did some research and it could be a vacuum leak. So I went back make sure everything was on right with some carburetor cleaner and found that the EGR hose had a leak where it plugs into the manifold. I bought a new o-ring gasket and re-installed it, drove it around for a while and the fault cleared.

The truck was running nice. Even a rattling nose it had upon hard acceleration went away. Tons of power and acceleration. Two days later the same P0171 & P0174 codes came back. I am at a dead end. Could be the MAF, O2 sensors, injectors, ect, but I don't think that is likely because the truck was running without any codes until I messed with the intake manifold.

I can still hear a leak where the EGR hose plugs into the manifold. I am thinking of using RTV around that damn hose.
Any advise. Sorry for the long post, I needed to vent.

Silverado, 2001, 5.3, 4WD
Original Poster
red_chaser
Firing on 1 cylinder [L1]
Firing on 1 cylinder [L1]
Posts: 17
Topics: 7
Joined: Jan 18 2012, 10:26pm
Years of membership: 2 years of membership2 years of membership
Location: South Texas
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: 5.3L Z71
Group Membership:
Registered users

Re: Lean Codes

Postby ASTE25 » Jan 20 2012, 4:04am

Does spraying brake cleaner around the intake produce a change in engine rpm?
Jordan
2013 Blue Granite Metalic Silverado 2500HD Z71 4X4 extended cab regular bed
6.6L Duramax/Allison 6 speed
Line-X premium over the rail (black)
User avatar
ASTE25
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 10933
Topics: 19
Images: 21
Joined: Jan 03 2011, 6:37am
Years of membership: 3 years of membership3 years of membership3 years of membership
Location: New Market, Alabama
Year: 2013
Make/Model: Chevrolet Silverado
Extra Info: 2500HD Z-71
Group Membership:
Automotive Technicians
Member Extraordinaire
Registered users

Re: Lean Codes

Postby red_chaser [OP] » Jan 20 2012, 8:48pm

ASTE25 wrote:Does spraying brake cleaner around the intake produce a change in engine rpm?


No change in RPM when spaying the intake.

Also, the P0171 & P0174 code have been on for 3 days, but today it decides to turn off on its own.
I'm confused. Don't know if it will stay off.
Original Poster
red_chaser
Firing on 1 cylinder [L1]
Firing on 1 cylinder [L1]
Posts: 17
Topics: 7
Joined: Jan 18 2012, 10:26pm
Years of membership: 2 years of membership2 years of membership
Location: South Texas
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: 5.3L Z71
Group Membership:
Registered users

Re: Lean Codes

Postby ASTE25 » Jan 20 2012, 10:08pm

I doubt it will stay off since the underlying problem is probably still there.
Jordan
2013 Blue Granite Metalic Silverado 2500HD Z71 4X4 extended cab regular bed
6.6L Duramax/Allison 6 speed
Line-X premium over the rail (black)
User avatar
ASTE25
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 10933
Topics: 19
Images: 21
Joined: Jan 03 2011, 6:37am
Years of membership: 3 years of membership3 years of membership3 years of membership
Location: New Market, Alabama
Year: 2013
Make/Model: Chevrolet Silverado
Extra Info: 2500HD Z-71
Group Membership:
Automotive Technicians
Member Extraordinaire
Registered users

Re: Lean Codes

Postby SilverSurfer » Jan 23 2012, 3:35am

If you can hear the leak then the lean codes will be back. I'd hold off on the rtv and try to repair it right. If you do end up using rtv, make sure it's high temp.
Image
User avatar
SilverSurfer
Staff Member
Staff Member
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 2365
Topics: 45
Images: 82
Joined: Jun 27 2011, 1:29am
Years of membership: 3 years of membership3 years of membership3 years of membership
Location: Phoenix, AZ
Year: 2003
Make/Model: Chevrolet Silverado
Extra Info: 5.3L Auto 2wd Posi
Group Membership:
Automotive Technicians
Global moderators
Registered users
Servicemen

Re: Lean Codes

Postby red_chaser [OP] » Jan 23 2012, 5:47pm

The SES light did come back on.

I checked it out this weekend and found I still had a leat at the EGR hose connection at the manifold. I tryed new o-ring gaskets; I even loosened up the EGR valve bracket to facilitate the manipulation of the hose, but that didn't work either. Everytime I sprayed carb cleaner the engine's idle would change.

I finally got fed up and put the o-ring gasket with a little RTV, left it over night to fully cure and no more leak! The SES light turned off and the truck runs like new. I hope the vibrations don't loosen it up or the RTV cause something else to go wrong.

I hope the SES light doesn't come back any time soon. The RTV is high temp.

How else could I have gotten the EGR hose not to leak? That one screw and flimsy aluminum bracket on that hose suck!
Original Poster
red_chaser
Firing on 1 cylinder [L1]
Firing on 1 cylinder [L1]
Posts: 17
Topics: 7
Joined: Jan 18 2012, 10:26pm
Years of membership: 2 years of membership2 years of membership
Location: South Texas
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: 5.3L Z71
Group Membership:
Registered users

Re: Lean Codes

Postby SilverSurfer » Jan 25 2012, 3:56am

The tube may have gotten bent. The RTV should be okay since you let it cure first.
Image
User avatar
SilverSurfer
Staff Member
Staff Member
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 2365
Topics: 45
Images: 82
Joined: Jun 27 2011, 1:29am
Years of membership: 3 years of membership3 years of membership3 years of membership
Location: Phoenix, AZ
Year: 2003
Make/Model: Chevrolet Silverado
Extra Info: 5.3L Auto 2wd Posi
Group Membership:
Automotive Technicians
Global moderators
Registered users
Servicemen

Re: Lean Codes

Postby waverider35904 » May 07 2013, 8:41pm

I'm having the same problem..Where did you apply the RTV?
waverider35904
Newbie
Newbie
Posts: 5
Joined: May 07 2013, 8:18pm
Years of membership: 1 year of membership
Location: Gadsden, Al
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: 5.3l Z71
Group Membership:
Registered users

Re: Lean Codes

Postby jck53151 » May 09 2013, 10:53pm

When removing the intake, you MUST remove the EGR, not just pull it out of the way. Much easier said than done as you have to get those 2 f@#!%*n screws out of the exhaust manifold. But once the original geometry is changed, it (to me) was near impossible to bend it right again. Went to bone yard and got a replacement for $20 ($150 at advance auto) and it ran like a champ.
jck53151
Newbie
Newbie
Posts: 8
Topics: 3
Joined: May 08 2013, 11:08am
Years of membership: 1 year of membership
Location: United States
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: Ext Cab 4x4 1500
Group Membership:
Registered users

Re: Lean Codes

Postby waverider35904 » May 09 2013, 11:47pm

I ended up with the EGR tube cracked in two spots from pulling it in and out so much trying to seat it. I checked the local junk yards and they didn't have one, so I ordered a new one from Advance auto....I guess that's part of learning. It'll take a few days shipping so hopefully when I get it, everything will be good. Thanks for the replies!
waverider35904
Newbie
Newbie
Posts: 5
Joined: May 07 2013, 8:18pm
Years of membership: 1 year of membership
Location: Gadsden, Al
Year: 2001
Make/Model: Chevrolet Silverado
Extra Info: 5.3l Z71
Group Membership:
Registered users
Next

Return to Engine

 

  • Similar topics
    Replies
    Views
    Last post

Common search terms

still right engine back same codes make lean nice thanks work think

It is currently Sep 30 2014, 8:53pm

  • Sponsor
Login  •  Register
SHOP TALK (Live Chat)
Engine Forum
EngineThis is where all of our engine discussion and conversation takes place. Talk about engine diagnostics, adjustments, modifications, performance and care. Motor tuning and repair to gain horsepower and fuel efficiency.
To create a new topic in Engine, click this button:
Previous topic Next topic
Sitewide News Sitemaps & Feeds

Who is online

Users browsing this forum: No registered users and 6 guests