MAS ??
Logistics Pro
Joined: Jan 2001
Posts: 3,740
Likes: 37
From: Central NYS
Get a 3 foot piece of fuel hose. Hold one end NEAR your ear. Probe th intake manifold gaskets with the other end to see if you can pin point the source.
(Spraying flammable liquids is questionable on these engines as the IAC quickly adjust for any change in RPM. Just my opinion. )
(Spraying flammable liquids is questionable on these engines as the IAC quickly adjust for any change in RPM. Just my opinion. )
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
Any fault that lets unmetered air into the intake tract will be a cause.
A Stethoscope with the probe removed can be used to locate and area you hear the sound coming from while the engine is running.
A spray may locate the area but it needs to be flammable.
You will listen closely for an idle change.
Also doing this while looking at the trim tables with a Scanner will make them move quickly in response to the spray added in with the gas combustion, as detected by the Ox sensors.
Good luck.
A Stethoscope with the probe removed can be used to locate and area you hear the sound coming from while the engine is running.
A spray may locate the area but it needs to be flammable.
You will listen closely for an idle change.
Also doing this while looking at the trim tables with a Scanner will make them move quickly in response to the spray added in with the gas combustion, as detected by the Ox sensors.
Good luck.
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Senior User
Joined: Nov 2008
Posts: 154
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Ok thanks. I borrowed a can of flammable carb cleaner from the neighbor and could not detect any changes in idle to my ear or my neighbor. For the life of me I cannot locate the leak but it is near the PCV valve within a 6 inch radius. I will try to look more this evening with the stethoscope. I am hoping its not a cracked intake.
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Senior User
Joined: Nov 2008
Posts: 154
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Yup its a cracked intake. I borrowed a mechanics stethoscope from a friend and pinpointed to the manifold between the throttle body and valve cover on the passenger side. It is on the back and with a mirror you can see a hairline crack. After Christmas I will order a new one. Is the Dorman a good brand, Rockauto has them for $165. In the mean time I mixed up some good ol JB weld for a temp fix. Will drive it tomorrow and see if it helped any.
Anything I need to worry about when swapping it out?
Anything I need to worry about when swapping it out?
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