Vacuum gauge on a Insight.

[Baltothewolf]

I need to know where to tap into. I got a vacuum/Boost gauge from summit racing for 10$, and I desire to install it tomorrow on my day off. Any advice is appreciated. I looked under the hood but there isn't a hole lot of vacuum lines going anywhere that are close enough to the manifold.

[Daox]

Any vacuum line after the throttle body will work fine.

[Chrysler kid]

I used the pcv hose. It's the one with the big Ole hose clamp on it in this picture

People who have never had one under estimate it's true value.

Hmm it appears I tapped the evap line, is there any secondary readings I could be observing

[Chrysler kid]

Hmm. This would explain the extra gas mileage I get on hot days if the hot tank builds extra vapors to send and mix with air, the wide band 02 would sense the extra power and restrict more fuel when in lean burn.

On one hot day I swear I could accelerate off of very little throttle this would help explain why

Vent lines from the fuel tank and carburetor bowl route vapors to the EVAP storage canister, where they are trapped and stored until the engine is started. When the engine is warm and the vehicle is going down the road, the PCM then opens a purge valve allowing the vapors to be siphoned from the storage canister into the intake manifold. The fuel vapors are hen burned in the engine.

Although now I'm thinking the fpr would give the best readings of engine fuel and vacuum draw but realistically the engine vacuum reading would be the exact same at every tap

To conclude I'm going to stick with the evap line just because it was easy to Tap and has a larger diameter

[Baltothewolf]

Originally Posted by Daox

Any vacuum line after the throttle body will work fine.

I was always told that the closer you get to the manifold, the more accurate your readings will be? I suffered from this on my Camry back when I drove it. When I tapped close to the brake booster, it was way off, by 3 or 4. When I moved it to right up against the manifold, it was reading dead on.