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Quick Question about EGR Valves. . .

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Old Mar 13, 2007 | 11:31 PM
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Default Quick Question about EGR Valves. . .

Are the EGR valves in our cars spring loaded to the open or closed position and then the energised solenoid moves the valve AGAINST spring pressure? :?
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Old Mar 13, 2007 | 11:36 PM
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Default Re: Quick Question about EGR Valves. . .

Originally Posted by MACDRIVE
Are the EGR valves in our cars spring loaded to the open or closed position and then the energised solenoid moves the valve AGAINST spring pressure? :?
Correct.
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Old Mar 13, 2007 | 11:40 PM
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Default Re: Quick Question about EGR Valves. . .

Originally Posted by PEARL_JAM
Originally Posted by MACDRIVE
Are the EGR valves in our cars spring loaded to the open or closed position and then the energised solenoid moves the valve AGAINST spring pressure? :?
Correct.
Ok if that'* correct, is it spring loaded to the open position or the closed position?
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Old Mar 13, 2007 | 11:50 PM
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It'* neither. Your valve (94 and newer) is a linear actuator. It uses pulse-width modulation to open the valve for varying amounts of 'on time'.

The 91-93 are a digital EGR with three separate solenoids, each opening a different diameter orifice. It uses combinations of these to get the correct flow.
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Old Mar 14, 2007 | 12:16 AM
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Originally Posted by willwren
It'* neither. Your valve (94 and newer) is a linear actuator. It uses pulse-width modulation to open the valve for varying amounts of 'on time'.
So with that being the case, and if the EGR valve were to quit operating, then that means it could stop at any number of positions between fully open and fully closed I assume; correct? :?
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Old Mar 14, 2007 | 01:04 AM
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Yes, that'* true. And while the earlier digital EGR is very easy to clean and put back in service, the Linear valve doesn't respond well as often.
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Old Mar 14, 2007 | 01:49 AM
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Alright great. Thank you for the answers Willwren.
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