Vacuum gauge problems :(

[DifferentPointofView]

So I got my vacuum gauge today... and its not working right.

For one, while it's idling, it's reading about 7, and on the highway, 6. on deceleration, it reads about 7.1. accelerations get to 5.

I switch to my grandpa's vacuum gauge from like the 60's or whenever, and it reads about 13. accellerations get to about 10.

The other thing is, when I use the gauge in direct. It reads about 10.2, and with my grandpa's, it reads 20 direct. on his gauge, 20 is normal for idle, and 15-19 is late ignition timing. but that was back in the day

What I don't get is why it reads about half of when it's in directly, cause there is no kinks in the hosing. and why in the world is the gauge from way back when engines were carbed correct but my brand new gauge is reading like crap

Some help would be appreciated.

[DifferentPointofView]

well... I'm going to return it. Hopefully they won't charge me shipping. cause then I would have spent more than the gauge itself in shipping, and then I'm be P*****

[tasdrouille]

I don't know how much you paid, or how fancy the gauge is/was, but for those on the cheap you can go to any local industrial components / pneumatics distributor and get a small mechanical gauge. I got the one I put in the TDI for 6 bucks.

[JohnnyGrey]

Where do you have the gauge hooked up? Is there any chance you could have it installed behind a check valve? The probability of bad readings from a brand new meter and another known good one is extremely low.