| 02-14-2014, 03:28 PM | #1 |
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Exhaust Valves... read everything... but?
Have been looking at my rear exhaust valves and it seems they operate like this:
Car off = valves open Car start = valves open, 90 seconds later valves close I never see them open from there until I stop the car again and turn the engine off. Have I got this right? Cheers Craig
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| 02-14-2014, 04:07 PM | #2 |
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The engine control operates the exhaust valve.
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| 02-15-2014, 03:17 PM | #3 | |
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Quote:
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| 02-16-2014, 06:10 AM | #4 |
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Some more info is in this thread/post
The diagram above forgot to mention what the different indices relate to (gear engaged/engine speed etc) The valve is vacuum operated and it depends on how long the car has been sitting if you see the valve open before starting the engine (the vacuum might slowly leak from the lines if the car is sitting for a while)
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| 02-16-2014, 10:45 AM | #5 |
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Valves are closed when the car is off. They use vaccum to open, unlike some older models that use vaccum to close. You used to be able to remove the vaccum like and cap off with a nipple and the flap(s) would stay open. Now, on the F10, you need to use heavy duty plastic or metal zip ties to hold the flap open where the vaccum line connects to the valve control on each outer muffler.
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| 02-24-2014, 07:01 AM | #6 | |
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Car off = closed Cold start = closed for 90 secs or so, then open up After warm up = open Still seems no conclusive info as to how it operates. |
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