vaccum leak
Post Fiend
Joined: Feb 2003
Posts: 6,940
Likes: 2
From: Eastern WA
It depends where you think it may be. Here are some pointers:
* Hook up a vaccum gage and see what it reads @ idle. It should be steady; no wandering. I'm not sure what year Ranger you have, but a carbureted engine should pull roughly 15 - 18 psi of vaccum @ idle. A low reading indicates a leak.
* Wandering, unsteady idle speed may indicate a vaccum leak. Keyword = may.
* Sometimes you can hear a leak; it will be a sucking sound or a faint whistle. Sometimes the leak is small and you have to have your ear close to it to spot it.
* Visually inspect all vaccum lines and fittings, especially any plastic ones, for damage.
* On intake manifolds, you can spray carb cleaner on sealing areas such as intake/head with the engine running; if there is a leak the idle will slow down.
* On components you may have to disconnect the component and compare how the engine runs with/without the componenet connected. The vaccum gauge will help with this as well as noting idle speed before and after.
* You can also spray carb cleaner on suspicious items, such as fittings and connections. A change in idle speed indicates a leak.
* Hook up a vaccum gage and see what it reads @ idle. It should be steady; no wandering. I'm not sure what year Ranger you have, but a carbureted engine should pull roughly 15 - 18 psi of vaccum @ idle. A low reading indicates a leak.
* Wandering, unsteady idle speed may indicate a vaccum leak. Keyword = may.
* Sometimes you can hear a leak; it will be a sucking sound or a faint whistle. Sometimes the leak is small and you have to have your ear close to it to spot it.
* Visually inspect all vaccum lines and fittings, especially any plastic ones, for damage.
* On intake manifolds, you can spray carb cleaner on sealing areas such as intake/head with the engine running; if there is a leak the idle will slow down.
* On components you may have to disconnect the component and compare how the engine runs with/without the componenet connected. The vaccum gauge will help with this as well as noting idle speed before and after.
* You can also spray carb cleaner on suspicious items, such as fittings and connections. A change in idle speed indicates a leak.
Last edited by CowboyBilly9Mile; Apr 23, 2004 at 05:42 AM.
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Nov 9, 2004 06:31 AM
