Ptfe?
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From: SW Va
The EGR valve is vacuum operated, via computer control of the VSV.
VSV= Vacuum Switching Valve. The computer sends electrical pulses to the VSV to have it send vacuum pulses to control the opening of the EGR valve.
If the VSV sticks open, or it's diaphragm leaks, such that it continues to apply vacuum to the ERG valve, it'll remain open & feed too much exhaust into the engine, same thing if the EGR valve sticks open because of excess carbon deposits.
I suppose the DPFE sensor, whos electrical output helps the computer decide what it needs to do about how much EGR application to apply, if acting out, could also send confusing signals to the computer & have it over apply EGR.
In any case, for some reason the computer believes it senses too much EGR feedback.
If your not clear about how the Rangers EGR system works, look in the "Tech Info" thread, located atop this forum, for a easy to understand EGR tutorial.
With the EGR valve being only 6 months old, I wouldn't think it's likely bad, or carboned up, unless the engine is burning a good bit of oil!!!!
So at this point I'd sorta suspect an acting out VSV.
It's easy to test. At cold idle, the EGR vacuum line from the VSV shouldn't have any vacuum on it. If it does, suspect the VSV.
Keep us posted on what you find.
VSV= Vacuum Switching Valve. The computer sends electrical pulses to the VSV to have it send vacuum pulses to control the opening of the EGR valve.
If the VSV sticks open, or it's diaphragm leaks, such that it continues to apply vacuum to the ERG valve, it'll remain open & feed too much exhaust into the engine, same thing if the EGR valve sticks open because of excess carbon deposits.
I suppose the DPFE sensor, whos electrical output helps the computer decide what it needs to do about how much EGR application to apply, if acting out, could also send confusing signals to the computer & have it over apply EGR.
In any case, for some reason the computer believes it senses too much EGR feedback.
If your not clear about how the Rangers EGR system works, look in the "Tech Info" thread, located atop this forum, for a easy to understand EGR tutorial.
With the EGR valve being only 6 months old, I wouldn't think it's likely bad, or carboned up, unless the engine is burning a good bit of oil!!!!
So at this point I'd sorta suspect an acting out VSV.
It's easy to test. At cold idle, the EGR vacuum line from the VSV shouldn't have any vacuum on it. If it does, suspect the VSV.
Keep us posted on what you find.
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Joined: Mar 2007
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Originally Posted by pawpaw
The P0402 code is for excessive EGR flow & seeing as how it's computer controlled through a vacuum swiching valve, seem to me a faulty VSV or dirty stickng EGR valve, belong on your suspect list.
Idle problems, when you call for defrosting & the AC compresor switches on, usually point to an acting out IAC.
Let us kow what you find.
Idle problems, when you call for defrosting & the AC compresor switches on, usually point to an acting out IAC.
Let us kow what you find.
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