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Bad EGR Code P1404

indygrandprix

New member
Have code P1404. From what I have read it is set when the PCM determines that the EGR is stuck partially open. It seems to come up more often as it gets colder out. I pulled the EGR off and cleaned it out, it wasn't very dirty to start with. The pintle moves up and down freely by hand and if I let it go to the closed position on its own and blow air thru it a very very very minimal amount gets by.

So is there anything else I should be looking at doing before replacing my EGR? (I did look at all the wires going to the EGR and they look alright and I have no other codes right now except a MAF code but I fixed that.)
 


I wish I had an answer for you on that, I have the same exact problem. it was happening only on cold starts and now that its getting colder its all the time, minus the rare drive cycle reset. I can delete them but it just makes the light go away, the code is seems to be pending most of the time.
 
You might try seafoaming your engine. As it gets colder carbon gets more brittle and breaks off easier. It only takes a tiny piece to hold the pintle open.
 
So I took the EGR off of another GP that has no check engine light and put it on my car and cleared the code and drove it around and after about 20 mins of driving it came back on. So now that i've ruled out the valve being bad and the wires running to it look OK what should my next move be. Bad PCM?
 
disconnect the egr connector, key to run do you have 5v ref voltage at the gray wire?

if that good I would key off...disconnect the ecm clear and blue connectors. do an ohms check of the signal wire- ecm clear connector pin 28 to the egr connector pin c brown wire. then ecm blue connector pin 31 to the egr connector pin b brown wire.
 
So I took the EGR off of another GP that has no check engine light and put it on my car and cleared the code and drove it around and after about 20 mins of driving it came back on. So now that i've ruled out the valve being bad and the wires running to it look OK what should my next move be. Bad PCM?


try changing the map sensor. not kidding. i had a egr code that was not giving up, many suggested changing it, and i did, along with the egr. been good so far.
 


Alright I will try that and see if changing the MAP help. I have a couple extra laying around. I also recently changed the MAF (Before i changed the EGR) wondering if the "new" (from the junkyard) maf could be part of the problem
 
try changing the map sensor. not kidding. i had a egr code that was not giving up, many suggested changing it, and i did, along with the egr. been good so far.

makes sense. the map and egr 5v ref source is supplied from the same source. if the map has shorted, it will bring down the 5volt ref power to all the sensors supplied on this circuit.
 


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