Low vacuum LT1
Thread Starter
Burning Brakes
Joined: Apr 2009
Posts: 1,185
Likes: 33
From: Charlotte Michigan
Low vacuum LT1
I have a vacuum gauge on my 93 Ruby withLT1 6 spd.. Normally it runs around 18-20. But a couple of days ago it was at 15 and if I barely touched the throttle it would drop off fast down to 5 or less.
What could be causing the loss?
Been thinking of new lines. Unsure of those sizes that are needed or a kit for them.
Anyone use silicone?
What could be causing the loss?
Been thinking of new lines. Unsure of those sizes that are needed or a kit for them.
Anyone use silicone?
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Try a new gauge. It may have become damaged from backfire. Mine sometimes sticks at zero for some reason then decide to work for no known reason. It seems to do this more in hot weather.
But when mine is working normal vacuum reading will slightly increase as I slowly open the throttle. And vacuum will drop to zero on WOT.
If you have a bouncing needle then that indicates a bad/burnt valve. Only you would know if the engine runs different now with the lower vacuum reading. I think if you truly had a 4-5 in Hg loss of vacuum you would notice a difference in the engine running and performance.
Hope this helps.
But when mine is working normal vacuum reading will slightly increase as I slowly open the throttle. And vacuum will drop to zero on WOT.
If you have a bouncing needle then that indicates a bad/burnt valve. Only you would know if the engine runs different now with the lower vacuum reading. I think if you truly had a 4-5 in Hg loss of vacuum you would notice a difference in the engine running and performance.
Hope this helps.
Thread Starter
Burning Brakes
Joined: Apr 2009
Posts: 1,185
Likes: 33
From: Charlotte Michigan
I was able yesterday to look under the hood. Everything looked ok until I moved a vacuum hose and it fell of the connector . The one barbed T was to large for the hose. Got a new connector today and replaced. Started engine and now works fine.
Just simple thing that overlooked before I moved the hose, otherwise it looked fine at first looks.
Just simple thing that overlooked before I moved the hose, otherwise it looked fine at first looks.
