Checking Vacuum Leaks - should i Use Carb Cleaner of WD40
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Checking Vacuum Leaks - should i Use Carb Cleaner of WD40
Im going to check some of my vaccum hoses for leaks
should i use wd40 or carb cleaner
all i know about checking for leaks is spray on the hoses and listen to the idle
is the noise a noticeable noise that you cant miss
also what does the liquids actually do by bean on a cracked hose
should i use wd40 or carb cleaner
all i know about checking for leaks is spray on the hoses and listen to the idle
is the noise a noticeable noise that you cant miss
also what does the liquids actually do by bean on a cracked hose
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Do you have a propane torch? You can run an unlit propane torch with the valve cracked open over the suspected hoses while your engine idles. If you pass it over a hose and it idles up and take the torch away and it idles down - the replace that hose. The propane going in the system will correct the Air Fuel ratio causing it to idle up.
Last edited by wardriver; 12-22-2008 at 08:35 AM.
#3
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Neither. Starting fluid is the thing to use. On the other hand, I've had vac leaks in the past and starting fluid didn't help track it down at all.
A propane torch is good because it will "smoke", so to speak. The air from the vac leak causes the gas to condense and appear as smoke. On the other hand, see above paragraph......third sentence.
The best thing, if neither of those methods work.....and you still suspect a vac leak, is find a mechanic with a vac leak detector. It purges smoke into the vacuum systems and smoke will pour out wherever the leak is. I had one at the cold start injector I couldn't find, and that found it in about 3min's......long enough for the smoke to fill the upper intake.
Oh, sometimes clamping all the hoses off.....one by one....at the source or termination of the line will do the trick. You've cut off the leak and the motor will either smooth out/speed up or slow down, depending on the behavior the suspected leak.
A propane torch is good because it will "smoke", so to speak. The air from the vac leak causes the gas to condense and appear as smoke. On the other hand, see above paragraph......third sentence.
The best thing, if neither of those methods work.....and you still suspect a vac leak, is find a mechanic with a vac leak detector. It purges smoke into the vacuum systems and smoke will pour out wherever the leak is. I had one at the cold start injector I couldn't find, and that found it in about 3min's......long enough for the smoke to fill the upper intake.
Oh, sometimes clamping all the hoses off.....one by one....at the source or termination of the line will do the trick. You've cut off the leak and the motor will either smooth out/speed up or slow down, depending on the behavior the suspected leak.
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i may try the propane trick (doesn't sound safe)
right now my truck idles at 600 rpm 750 is normal
i throw the egr code
i know some of my hoses are a little cracked so im gonna eliminate that problem
also i need to check my egr with a vacuum pump
i can also try starting fluid ill figure it out any other tips
right now my truck idles at 600 rpm 750 is normal
i throw the egr code
i know some of my hoses are a little cracked so im gonna eliminate that problem
also i need to check my egr with a vacuum pump
i can also try starting fluid ill figure it out any other tips
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the only thing about propane is it will settle in valleys, so if an amount of it settles somewhere and gets ignited then its a very big flash
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