Brake booster vacuum leak

ctuinstra

Goblin Guru
Kaleb was out logging some data today so I could continue tuning the car. When he come to a stop, the engine would idle up to 2300 RPM. He also heard a noise from the engine he hadn't heard before. Got the car home and the AFR was off the chart! It was so lean at idle, it wouldn't hardly idle. I know it wasn't the tune because it had been mostly rich. Nothing I could do would affect the AFR at idle. I knew it had to be a vacuum leak or something but there isn't really many vacuum lines. So just poking around I pulled a bit on the rubber hose of the vacuum line to the brake booster and it fell off! The hose clamp had let go. I really don't like the over-sized hose squished down to the hard line. Does anyone have a better way of adapting the two lines? A hard line press on to a hose barb would be best.
 

ctuinstra

Goblin Guru
I seen that after I posted. I like the idea but was hoping to find something in brass or anodized aluminum. I would really love if I could find the same o-ring press on fitting like those used on the fuel pump.
 

ctuinstra

Goblin Guru
I believe I have it fixed up good now. I was making things more difficult than needed. I replaced the over-sized hose with this one. This fits over the snap fitting on the intake and just slips over the hard nylon tubing used for the brake booster. By itself it's pretty much leak-proof but with a few clamps it should be solid.

This is the Gates 18031 hose. It's available just about everywhere. Also if you have a SS/SC car, the overflow hose from the coolant of the intercooler is almost the exact same hose, just shorter. So if you were to leave your hard nylon tube longer, it would work just fine. Ours is too short so this new Gates hose came to the rescue.

https://www.jegs.com/i/Gates/465/18031/10002/-1
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I also used these clamps which I like a lot better that typical hose clamps for smaller OD hoses.

https://www.amazon.com/gp/product/B07YZDDQMX/ref=ppx_yo_dt_b_asin_title_o00_s01?ie=UTF8&psc=1

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I often wonder if this was contributing to some of the tuning issues I have been having. I'm getting scanning data that tends to jump all over the place which makes it very hard to dial in. We will see soon. I hope to get back to tuning this weekend if it's not too dang hot again.
 
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