question about intake manifold vacuum leak
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From: Lake Tapps, WA
question about intake manifold vacuum leak I noticed today that my intake has a slight vacuum leak by the 4 and 6 cylinders, when I spray carb cleaner between the head and intake manifold the rpm rises slightly. Hasn't thrown any codes, doesn't miss, I found it by accident when I was spraying carb cleaner to remove some oil.
Should I worry about it?
Should I worry about it?
TECH Enthusiast
Joined: Sep 2005
Posts: 503
Likes: 54
From: TX
I actually just fixed a vacuum leak a few days ago. I hooked up my scanner and the LTFTs were maxing out. I check the TB and everything past the MAF first and all was good. So I pulled the intake and replaced gaskets. Its not good to have leaks, theyll make it do funky things. It was pretty easy to do, took a couple hours. Also it gives you a chance to clean the intake out really good inside and out.
TECH Enthusiast
Joined: Sep 2005
Posts: 503
Likes: 54
From: TX
Long term fuel trims.
Basically the o2 sensors are detecting a lean mixture from air that is entering the combustion chamber that is not going through the MAF first. So the PCM adds fuel to compensate(LTFT). It can compensate about 25% of what it should be by either adding or subtracting fuel.
It did develop a miss, thats why I hooked up the scanner to see what was up.
Basically the o2 sensors are detecting a lean mixture from air that is entering the combustion chamber that is not going through the MAF first. So the PCM adds fuel to compensate(LTFT). It can compensate about 25% of what it should be by either adding or subtracting fuel.
It did develop a miss, thats why I hooked up the scanner to see what was up.
