Is my L76 intake messed up?
08-05-2007, 07:04 PM
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Is my L76 intake messed up? It might be normal, but on the back of my L76 intake manifold the tube on the back that connects to the brake booster can be pushed into the intake. Unlike my LS1 and LS6 intake which were stationary. I just fired up my car and the rpms at idle jumped way up so high that I had to shut off the engine. Im woried that the area around the tube in the back of the intake could be the source of a vacuum leak.
08-05-2007, 07:49 PM
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First, I think that this post should be on Gen IV External Engine. If you want to check for induction/vacuum leaks, there are a couple of pretty standard ways to do this.
1. Get a hose or stethoscope (open end of tube only) and move it all around the intake and any lines that run to it. There may be a distinct hissing noise if you can get the hose/tube close to the leak.
2. Take some aerosol lubricant (WD-40, etc.) or a propane torch (unlighted) and spray around the intake and see if the idle speed changes.
Also, do you have a WBAFR gage? If there is much of a leak, the AFR will go lean.
Steve
1. Get a hose or stethoscope (open end of tube only) and move it all around the intake and any lines that run to it. There may be a distinct hissing noise if you can get the hose/tube close to the leak.
2. Take some aerosol lubricant (WD-40, etc.) or a propane torch (unlighted) and spray around the intake and see if the idle speed changes.
Also, do you have a WBAFR gage? If there is much of a leak, the AFR will go lean.
Steve
08-06-2007, 06:31 PM
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thanks Well it looks like the exact thing that I whought was messed up on my L76 intake was the cause of a huge vaccum leak, subsequently causing the rpms to sky rocket. Is anyone elses L76 intake like this? What needs to be done to seal it off. I am talking about the hard elbow on the back of the intake that connects to the brake booster. The entire circular piece that it is connected to is able to move around in and out of the intake. Theres no way that this can be air tight in my opinion.
08-06-2007, 08:16 PM
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It sounds to me like that fitting is broken. Mine was not loose at all and the fitting/hose barb was sealed. The shop had to cut off the end of the fitting to connect up the booster hose.
08-07-2007, 04:05 PM
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cracked I figured out why that elbow is messed up. I took a closer look at the intake and found out that it is cracked. The sponsor that I bought it from better have insurance on that package, because there is no way I am going to buy another one. I am pissed. I have never had more problems with a project in my life.
