Mastering the Basics–Reading A Vacuum Gauge. By Ken Layne. Evaluating engine operation and pinpointing specific problems requires a comprehensive .
i got a vacumm gauge installed in my car, it used to read around 20 during idling. recently it read lower, about slightly lower than 15 (nearer to 0 .
To do this, it's important to judge engine performance by the general location and action of the vacuum gauge needle, rather than just by a vacuum reading.
You may need to T a vacuum line, which may or may not have come in your kit. Once you've connected the gauge you should see a STEADY reading at idle with
Here is a combination fuel and vacuum gauge http://amzn.to/2pQkFL6. NORMAL ENGINE: Steady reading of 17-21 when engine is idling. NORMAL ENGINE: .