What cause engine to run lean?

Tiny
JOE1953
  • 1996 CHEVROLET SILVERADO
  • 222,000 MILES

Engine have a misfire at idle in #5 cylinder Spark plug wires, Spark plugs, compression or good #5 Spark plug have white carbon build up on it, this engine have a Throttle Body.

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Saturday, October 6th, 2012 AT 4:44 PM

37 Replies

Tiny
ASEMASTER6371
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  • 25,533 POSTS

Missfire comes from, compression, vacuum leak, low fuel pressure, injector issue. All these need to be checked.

Roy

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Saturday, October 6th, 2012 AT 4:46 PM
Tiny
JOE1953
  • MEMBER

How do I check for vacuum leak.

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Saturday, October 6th, 2012 AT 4:54 PM
Tiny
ASEMASTER6371
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Well, you really need a smoke machine, which is not in everybodys toolbox.

You can try spraying a little carb cleaner around the intake where it meets the head and see if the rpm rise or change

Roy

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Saturday, October 6th, 2012 AT 5:00 PM
Tiny
JOE1953
  • MEMBER

I did spray a little carb cleaner around the upper intake rpm didn't change, what is a smoke machine.

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Saturday, October 6th, 2012 AT 5:20 PM
Tiny
ASEMASTER6371
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You should let a shop do this for you. It is an 1200 dollar tool that injects smoke in the system and you can identify the leak with the smoke.

Roy

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Saturday, October 6th, 2012 AT 10:14 PM
Tiny
JOE1953
  • MEMBER

About how much it will cost for a shop to identify the leak.

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Sunday, October 7th, 2012 AT 3:28 AM
Tiny
CJ MEDEVAC
  • EXPERT
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THIS IS CRUDE--BUT IT WORKS!

http://www.youtube.com/watch?v=zMok2y05jNE

THE MEDIC

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Sunday, October 7th, 2012 AT 3:59 AM
Tiny
KHLOW2008
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Nice one CJ, but if a Havana is required, it is not to be too cheap, lol.

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Sunday, October 7th, 2012 AT 8:34 AM
Tiny
CJ MEDEVAC
  • EXPERT
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COULD ALSO BE CONNECTED TO A CERTAIN POLITICIAN

BE CERTAIN YOUR SYSTEM IS CAPABLE OF HANDLING THAT KIND OF PRESSURE

THE MEDIC

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Sunday, October 7th, 2012 AT 12:39 PM
Tiny
JOE1953
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I can't watch the videos do I need to install something on my computer before I can watch the video.

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Monday, October 8th, 2012 AT 4:26 PM

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