Mechanics

WOULD A CLOGGED EGR VALVE CAUSE ROUGH IDLE IN 99 ?

1999 Ford Taurus


got a diag. Code was "egr low pressure". It also kinda idles rough. I plan on replacing the egr value, pipe and pressure sensor. ANY feedback on this topic is greatly appreciated.
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Emilys
May 16, 2012.




If its p0401, remove egr then use a steel coathanger and push it through the port all the way through to the throttle plate. Clean the egr of carbon and vacuum test it. If it opens and. Closes as it should and holds vacuum, put it back on. If the light and code. Come back. Replace the sensor.

Merlin2021
May 16, 2012.
Don't forget the DPFE sensor.

Wrenchtech
May 16, 2012.
A "clogged" EGR valve could not cause a poor idle, as it's supposed to be closed at idle. Pinging under acceleration, higher operating temperatures maybe. But it would have to be stuck open (or otherwise open when it's not supposed to be, which includes at idle) to cause a poor idle quality.
So, which actual code was this anyway? Because I can't think of any "low pressure" that would relate to the valve itself. It operate on vacuum not pressure. Maybe the pressure sensor, but not the valve.
If we had the actual code, maybe someone who knows what's what could clear this up, and save you a lot of money wasted on perfectly good parts being replaced?
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Tiny
Songforw
May 17, 2012.
It can cause poor idling if the port is clogged all. The wau to the throttle plate. Because this will affect the idle. Air control valve. Remove this as well and check the pintle.

Merlin2021
May 17, 2012.
With no code its a gess. Hi fail rate is the dpfe. None of which would make idle poor. Only if it was sticking open.

Djcl
May 17, 2012.
It will if it's clogged with carbon and not allowing the pintle to seat.

Wrenchtech
May 17, 2012.

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