2002 Yukon

[hoseman]

Hello , just thought I would ask if any one could lead me in the right direction.What has been happening is the service engine light is comming on, not all the time but freqent.The motor seems to run rough at an idle it goes from 800 rpm to 400 rpm but smooths out past idle.I have changed plugs and wires ,fuel filter ,and put fuel treatment in and cleaned the throdle body,plus done a smoke vacum ckeck it was ok. The code says o2 sensor on both sides,or lean bank 1and 4, and once showed a miss in 4.I have taken it to be check when running bad on several occasions and when I shut the motor off to go in then came back out with the computer it ran fine. any thoughts

[minibike132]

Best guess clean the throttle plates.

[minibike132]

Best guess clean the throttle plates.

 

 

errr plate.

[minibike132]

Also certian intakes have a leaking vacuum issue. I didn't notice what engine you have.

 

Subject:Cold Engine Idle Misfire Or DTCs P0171 P0174 - keywords 4.8 5.3 6.0 air cold crack hesitate idle intermittent internal intake leak lean misfire miss P0171 P0174 P0300 power rough surge vacuum #PIP3232B - (02/07/2007)

 

 

 

 

Models:2002-2005 Cadillac Escalade

 

 

1999-2005 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe, Trailblazer

 

 

1999-2005 GMC Savana, Sierra, Yukon

 

 

2003-2005 Hummer H2

 

 

 

 

This PI was superseded to update parts information. Please discard PIP3232A.

 

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss1-1899786">

Condition/Concern:

99 through 05 GEN III truck engines may experience any of the following:

 

1. 
   <LI type=1>A cold rough idle that diminishes as the engine warms up. <LI type=1>Possible DTCS P0171, P0174, or P0300.
   
2. Random misfires at idle.
   

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss2-1899786">

Recommendation/Instructions:

The intake gasket seals may be leaking around the intake ports, causing a lean condition. The intake gasket seals may leak around the bottom side of the port, making it a challenge to detect the vacuum leak. The technician may also notice lower than normal MAF readings if the intake seals are leaking.

 

1. 
   <LI type=1>If leaking intake gasket seals are found, replace the intake gaskets. During the repair be sure to use the current GMSPO part number for replacement intake gaskets. The current GMSPO part number for intake gaskets will have a teal green intake gasket seal. The old version of the intake gaskets were orange in color. Use only the teal green colored gaskets for a repair.
   
2. The intake plenum should also be checked for excessive warpage that may cause an uneven clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced. Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area should be replaced". Intake warpage is measured at the gasket sealing surfaces, and should be measured within a 200 mm (7.87 in) area. This measurement is across only two of the intake runner port openings. Measurements taken across the entire distance of all four intake runner ports will lead to unnecessary manifold replacements.
   

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

 

 

You didn't list the code #s but I assume they are lean codes not o2 codes. The way I find this is watching my fuel trim value while spraying carb clean around intake runners.

[hoseman]

Also certian intakes have a leaking vacuum issue. I didn't notice what engine you have.

 

Subject:Cold Engine Idle Misfire Or DTCs P0171 P0174 - keywords 4.8 5.3 6.0 air cold crack hesitate idle intermittent internal intake leak lean misfire miss P0171 P0174 P0300 power rough surge vacuum #PIP3232B - (02/07/2007)

 

 

 

 

Models:2002-2005 Cadillac Escalade

 

 

1999-2005 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe, Trailblazer

 

 

1999-2005 GMC Savana, Sierra, Yukon

 

 

2003-2005 Hummer H2

 

 

 

 

This PI was superseded to update parts information. Please discard PIP3232A.

 

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss1-1899786">

Condition/Concern:

99 through 05 GEN III truck engines may experience any of the following:

1. <LI type=1>A cold rough idle that diminishes as the engine warms up. <LI type=1>Possible DTCS P0171, P0174, or P0300.

    

2. Random misfires at idle.

    

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss2-1899786">

Recommendation/Instructions:

The intake gasket seals may be leaking around the intake ports, causing a lean condition. The intake gasket seals may leak around the bottom side of the port, making it a challenge to detect the vacuum leak. The technician may also notice lower than normal MAF readings if the intake seals are leaking.

1. <LI type=1>If leaking intake gasket seals are found, replace the intake gaskets. During the repair be sure to use the current GMSPO part number for replacement intake gaskets. The current GMSPO part number for intake gaskets will have a teal green intake gasket seal. The old version of the intake gaskets were orange in color. Use only the teal green colored gaskets for a repair.

    

2. The intake plenum should also be checked for excessive warpage that may cause an uneven clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced. Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area should be replaced". Intake warpage is measured at the gasket sealing surfaces, and should be measured within a 200 mm (7.87 in) area. This measurement is across only two of the intake runner port openings. Measurements taken across the entire distance of all four intake runner ports will lead to unnecessary manifold replacements.

    

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

 

 

You didn't list the code #s but I assume they are lean codes not o2 codes. The way I find this is watching my fuel trim value while spraying carb clean around intake runners.

[hoseman]

Also certian intakes have a leaking vacuum issue. I didn't notice what engine you have.

 

Subject:Cold Engine Idle Misfire Or DTCs P0171 P0174 - keywords 4.8 5.3 6.0 air cold crack hesitate idle intermittent internal intake leak lean misfire miss P0171 P0174 P0300 power rough surge vacuum #PIP3232B - (02/07/2007)

 

 

 

 

Models:2002-2005 Cadillac Escalade

 

 

1999-2005 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe, Trailblazer

 

 

1999-2005 GMC Savana, Sierra, Yukon

 

 

2003-2005 Hummer H2

 

 

 

 

This PI was superseded to update parts information. Please discard PIP3232A.

 

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

 

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss1-1899786">

Condition/Concern:

99 through 05 GEN III truck engines may experience any of the following:

1. <LI type=1>A cold rough idle that diminishes as the engine warms up. <LI type=1>Possible DTCS P0171, P0174, or P0300.

    

2. Random misfires at idle.

    

<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1899786&psdid=257&evc=sm#ss2-1899786">

Recommendation/Instructions:

The intake gasket seals may be leaking around the intake ports, causing a lean condition. The intake gasket seals may leak around the bottom side of the port, making it a challenge to detect the vacuum leak. The technician may also notice lower than normal MAF readings if the intake seals are leaking.

1. <LI type=1>If leaking intake gasket seals are found, replace the intake gaskets. During the repair be sure to use the current GMSPO part number for replacement intake gaskets. The current GMSPO part number for intake gaskets will have a teal green intake gasket seal. The old version of the intake gaskets were orange in color. Use only the teal green colored gaskets for a repair.

    

2. The intake plenum should also be checked for excessive warpage that may cause an uneven clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced. Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area should be replaced". Intake warpage is measured at the gasket sealing surfaces, and should be measured within a 200 mm (7.87 in) area. This measurement is across only two of the intake runner port openings. Measurements taken across the entire distance of all four intake runner ports will lead to unnecessary manifold replacements.

    

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

 

 

You didn't list the code #s but I assume they are lean codes not o2 codes. The way I find this is watching my fuel trim value while spraying carb clean around intake runners.

 

[hoseman]

ty I just got the same info from some else about the gasket.The motor is 5.3 flex fuel and the codes that came up are lean bank 1 and 4 with both o2 sensors codes .I think I may start the motor when cold and spray non flamalbe brake cleaner on the intake to see if thats the problem, does that sound like the right thing to do?I have also cleaned the mass air with cleaner . Would this show up in a smoke test? thanks again

[hoseman]

I also was wondering it does seem to have the most trouble in the mornings at a cold start,Do you think the alum. heads are expanding to seal the leak as the engine warms ? The funny thing is it has ran good today as we drove and it seem to be fine now but the truck sits all nite it runs rough in morning.

[minibike132]

Try the first post of cleaning throttle plate first not the mass air flow. Just spray some top engine cleaner into the throttle plate and brush with tooth brush or like. As for how to check the intake (yes usually worse cold but so is dirty throttle plate) I usually use carb clean while watching my o2 to see if it goes rich. Problem with doing it without being able to see the #s on a scanner is the computer adjusts so fast you may miss it.

[Mikeee]

Get it fixed?

 

Anyway, to sorta ride this thread....

I've got the following codes today.

P0174

01/03

 

P0171 Pd

02/03

 

P0174 Pd

03/03

 

It's a '03 Savana w/ 5.3 at 157,000 miles

I just bought it used with 156,000 miles.

Don't know it's true previous service life.

Ran the VIN in the GM system and nothing came up for service work.

 

Cleared the codes.

Wait-n-see.

 

Yes, I saw the TSB's about the intake leaks.

Hope not it.

How hard to do myself?

I've done the up/lo intake on 3.8.

Also saw something/somewhere about the injector connectors dirty/corroded.

 

I'm gonna start with the TB cleaning & MAS cleaning & fuel filter replacement.

 

Any thoughts ? ? ?

[klunkerbus]

This winter, my 04 Tahoe Z71 got very predictable in throwing the P0171 and P0174 codes as the engine was warming up and it was about 25 degrees F outside, especially if I sat idling for any time. Replacing the intake manifold gasket was next on my list of things to do (after throttel body and MAF), but I traded it in on something else before I got around to it. Unfortunately, I bought the GM gasket before I decided to trade the Tahoe in. If someone is interested in buying it, send me a message. I'm willing to part with it at a loss. It is has the new teal-colored seal mentioned in the TSB and is still in the original package. I believe the same gasket kit fits 4.8, 5.3, and 6.0L engines in years 99-06. P/N is GM 89060413.

 

Note: I'll be on travel March 11 and 12th and then again from March 16 through March 22. I won't be able to respond to messages in those windows.

[gexline21]

75% sure its the intake gaskets leaking, the flex fuel motors where the first ones to get the new designed intake gaskets. Id change the gaskets, clean the head surface and recheck - i bet it will fix them.

Hello , just thought I would ask if any one could lead me in the right direction.What has been happening is the service engine light is comming on, not all the time but freqent.The motor seems to run rough at an idle it goes from 800 rpm to 400 rpm but smooths out past idle.I have changed plugs and wires ,fuel filter ,and put fuel treatment in and cleaned the throdle body,plus done a smoke vacum ckeck it was ok. The code says o2 sensor on both sides,or lean bank 1and 4, and once showed a miss in 4.I have taken it to be check when running bad on several occasions and when I shut the motor off to go in then came back out with the computer it ran fine. any thoughts

[andrzar]

This winter, my 04 Tahoe Z71 got very predictable in throwing the P0171 and P0174 codes as the engine was warming up and it was about 25 degrees F outside, especially if I sat idling for any time. Replacing the intake manifold gasket was next on my list of things to do (after throttel body and MAF), but I traded it in on something else before I got around to it. Unfortunately, I bought the GM gasket before I decided to trade the Tahoe in. If someone is interested in buying it, send me a message. I'm willing to part with it at a loss. It is has the new teal-colored seal mentioned in the TSB and is still in the original package. I believe the same gasket kit fits 4.8, 5.3, and 6.0L engines in years 99-06. P/N is GM 89060413.

 

Note: I'll be on travel March 11 and 12th and then again from March 16 through March 22. I won't be able to respond to messages in those windows.

 

I know it's 7 month later, but wonder if you still have this gasket? I have the same problem on my Denali. You can write me to [email protected] if you still have it. Thanks!