Originally Posted by
scottfab and Dynomite
This is not normal. 10sec is too short of an interval. 12-15 seconds is stated in first post.
I see. And the pump is also mentioned, however, if you look at the title of this thread you may see something interesting =D>
It's easy to get it to 30sec or more. Yes....install a complete new system of vacuum lines and connectors.
So the only way to get to 30sec (or much more) is to replace everything? I don't think so.
DON'T rip it all out ! What???.........many of us remove the vacuum system completely (remove, not rip)
Don't confuse the guy. "many of us" is relative. I'd say a half dozen +/- a few have ripped the secondary system out. There are literally thousands of ZR-1 with the secondary systems in place. And guess what? They work.
Just fix it like you would a burned out light bulb. A burned out light bulb 30 feet in the air and no ladder 
I agree there are those that would rather throw a rock at the bulb than get a ladder. Or they might even cut the pole down that has the light on it.
You also should not trade the car in for a new one
when the ash tray is full. Or remove the plenum when you have a very very small vacuum leak on a 20 year old car.
We're not even to the point of knowing it's under the plenum. More confusion. A "very very small vacuum" leak is relative. A 10 sec cycle time is not a "very very small vacuum leak". I'd call it a moderate leak to be dealt with. There is absolutely no reason the secondary vacuum system cannot be fixed and fixed to a point where it works for 10yrs before a "very very small leak" appears again. A lot of it has to to with how dusty and dirty the air is in which the car is driven. If you drive your car on dirt roads in dry conditions you're simply going to have more plugged filters and dirty check valves.
Start with the basics.
Find the hard plastic hose that comes out of the pump and
pull it out. Then put you finger over the side coming from the pump.
It should run a bit then stop for an indefinite period of time. Checking for an internal leak in vacuum pump....but even then if it is the vacuum pump back leaking I would not replace vacuum pump for such a small leak.
There is no reason to replace the pump for such a issue as contamination or what's more likely, a leaking diaphragm.
I have a tread on fixing the diaphragm or it maybe attached to a previous tread on the secondary system. .
Report back then we can direct you to the next step. Just explain your version of the steps here 
I could but I could also describe how to empty the ash tray. Problem with that is it is premature to go into the LT5 rebuild when it's not clear that's where the problem is 
(or find the old thread that covers this to send you too)
When you find the old thread that covers this (there are many) just post it here so we can all see what you found
In good time. In good time. Let's find out if it's needed.
Quote:
Originally Posted by Dynomite
When you find the old thread that covers this (there are many) just post it here so we can all see what you found  |
In good time. In good time.