Code 55 and 56
#1
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Code 55 and 56
Got both of these today. Cleared them, and they came back. EGR solenoid 3 and Quad B fault. FSM says they are likely related, but I'm not likely to get a Tech 1 on it to verify. Can this be fixed by lubing up the EGR valve?
#4
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The quad drivers are mini-relays in the PCM. The drivers are protected by mini circuit breakers. The quad driver code is usually from a fault with the drivers (PCM) themselves or the device the driver operates is drawing too much current. See how many ohms resistance solenoid 3 has.
#5
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Originally Posted by willwren
You would have had to have had the code at the track (and a CEL).
Clean and lube. I do it a couple times a year. I've never seen a quad related to mine.
Clean and lube. I do it a couple times a year. I've never seen a quad related to mine.
#7
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Right. I was thinking it could be open when I've got it loaded up to 1500-1800 rpm waiting for green, and when I launched, it didn't shut as quickly as it should.
#8
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I checked on the way home. The PCM does command EGR shaft #3 open when I'm preloading at 1500-1800. If it was sticking or slow, I'm pretty sure that would cause a bunch of knock counts.