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Rough Idle 08 Silverado

dirtracer455

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dirtracer455 Enthusiast

dirtracer455

Posted
Posted

Hey everyone,

 

So I just started my truck up tonight and found that it had a MUCH rougher idle than normal. You could feel it through the steering wheel, as well as the pedals.

I let the engine warm up for about a minute and no change. I pulled out of the driveway and after pulling forward about 100ft the rough idle stopped. Drove the truck for awhile tonight and noticed nothing else.

 

Just bought this truck a couple months ago and have never had this problem before.

 

Hope everything is alright please advise!

 

My truck is a 2008 LTSilverado 4x4 [About 2000 miles]

DamageInc Enthusiast

DamageInc

Posted
Posted
Hey everyone,

 

So I just started my truck up tonight and found that it had a MUCH rougher idle than normal. You could feel it through the steering wheel, as well as the pedals.

I let the engine warm up for about a minute and no change. I pulled out of the driveway and after pulling forward about 100ft the rough idle stopped. Drove the truck for awhile tonight and noticed nothing else.

 

Just bought this truck a couple months ago and have never had this problem before.

 

Hope everything is alright please advise!

 

My truck is a 2008 LTSilverado 4x4 [About 2000 miles]

 

Sorry that I can't be of any help, but something tells me that it will be related to the AFM. Keep us posted....

98 Z71 SLT Senior Enthusiast

98 Z71 SLT

Posted
Posted

100% Agreed with above post.

 

GM Engineering is having numerous problems with Active Fuel special lifters actually "coming-apart" in the engine block, creating a mess, and causing misfires on actual AFM related cylinders.

 

You want GM Document 08-06-01-018A in your hands when returning to the dealership.

 

Get in touch with MS3DALE or MCueva...they can print the document to fit this screen.

pm26 Senior Enthusiast

pm26

Posted
Posted
100% Agreed with above post.

 

GM Engineering is having numerous problems with Active Fuel special lifters actually "coming-apart" in the engine block, creating a mess, and causing misfires on actual AFM related cylinders.

 

You want GM Document 08-06-01-018A in your hands when returning to the dealership.

 

Get in touch with MS3DALE or MCueva...they can print the document to fit this screen.

 

 

This does not surprise me. I have been criticized and ridiculed for expressing negative opinions about the AFM, but looks like I was right about potential long term issues with this system. I almost bought a new 07 left over Impala SS, except it has that darn AFM which I cannot stand.

tobias Senior Enthusiast

tobias

Posted
Posted
100% Agreed with above post.

 

GM Engineering is having numerous problems with Active Fuel special lifters actually "coming-apart" in the engine block, creating a mess, and causing misfires on actual AFM related cylinders.

 

You want GM Document 08-06-01-018A in your hands when returning to the dealership.

 

Get in touch with MS3DALE or MCueva...they can print the document to fit this screen.

 

 

This does not surprise me. I have been criticized and ridiculed for expressing negative opinions about the AFM, but looks like I was right about potential long term issues with this system. I almost bought a new 07 left over Impala SS, except it has that darn AFM which I cannot stand.

 

 

:dunno: It'll be okay. :cheers:

minibike132 Senior Enthusiast

minibike132

Posted
Posted
100% Agreed with above post.

 

GM Engineering is having numerous problems with Active Fuel special lifters actually "coming-apart" in the engine block, creating a mess, and causing misfires on actual AFM related cylinders.

 

You want GM Document 08-06-01-018A in your hands when returning to the dealership.

 

Get in touch with MS3DALE or MCueva...they can print the document to fit this screen.

 

Where did you get the "coming apart" I think the engineering quote would be "collapsed afm lifter". I have had a few collapsed and it makes a very noticeable collapsed lifter noise not just a missfire. As far as a collapsed lifter causing long term engine issues the jury is out. The worst IMO that could happen is a flat cam lobe but I wouldn't be too worried about it unless it went on for a long time. I had a used Trailblazer with afm and a collapsed lifter come in from auction. The old lady liked the vehicle and I was pretty confident that there was no long term dammage that after I fixed it we bought it.

 

OP:I agree that it may be related to afm but I doubt it is a lifter, they don't usually fix themselves.

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