05 Pacifica, 3.5L (211k Miles) threw the p0403 EGR Ckt, I instinctively replaced the EGR valve. After a couple of days the car went back to running rough/surging. I noticed that after I cycle power to the PCM it'll get a couple of days of good running out of it while the computer "learns" I would guess. I also noticed that the p0403 and p0406 fault codes reappear immediately and are not clearable via the scanner. Does anyone know the pin outs/assignments and voltage levels for the connector? I think it's time to check wiring - at least power and ground, no scope so I can't check for noise or signal fluctuation. Any other ideas would be greatly appreciated. Thanks

 

PIN-OUT


EGR SOLENOID - BLACK 6 WAY
CAV CIRCUIT FUNCTION
1 K34 20DB/LG EGR SIGNAL
2 F855 20PK/YL 5 VOLT SUPPLY
3 K900 20DB/DG SENSOR GROUND
4 Z335 18BK/WT GROUND
5 - -
6 K35 18DB/VT EGR SOL CONTROL

PAy particular attention to Exhaust crossover pipe for contact with solenoid harness...

Also keep in mind, if a short circuit occurs in a PCM output...The "CKT DRIVER" is disabled....resetting power to pcm is NOT the answer , but rather a "Byproduct" of the "Failsafe" that was engineered into the module....

I have also had nothing but BAD LUCK with aftermarket valves....Spend the few extra bucks on a mopar valve..it will save you alot of grief on the other end of the line.

 

Fantastic, thanks for the help. I agree pcm reset is not the answer. I noticed it as a byproduct of pulling the battery to gain access to the bottom 2 bolts. I now have my nights work planned. Thanks again, btw I think you're correct with the aftermarket egr valve, I really doubt I'll find anything with the wiring.

 

OK - checked wiring, saw no shorts and high resistance between pins and decided to get a Mopar EGR valve. Unfortunately with the same results. Then powered up the car and measured voltages at each pin with the following results:

1 K34 20DB/LG EGR SIGNAL - 5V
2 F855 20PK/YL 5 VOLT SUPPLY - 5V
3 K900 20DB/DG SENSOR GROUND - Ground (26 Ohms to chassis ground)
4 Z335 18BK/WT GROUND - 10V???
5 - -
6 K35 18DB/VT EGR SOL CONTROL - ~-.1V

I wasn't paying attention when I measured voltages before getting the Mopar part but pin 4 at 10V seems wrong. Where's this signal come from?

Also another symptom that my wife had complained about but never happened (until today) when I drove it - the engine sputters, drops to very low RPM, gas pedal has no effect - cannot rev engine at all, occassionally surges as if firing on a couple of cylinders, absolutely no power. Kill the engine and immediately restart and everything is OK. Another possible clue, the ODBC scanner can read the fault code (P0403) but has an ERR when trying to erase it about 50% of the time... Any thoughts?

 

It absolutely is WRONG.....It is a chassis ground...there shouldnt be any voltage at all.

Pin 3 is a bit confusing..it says sensor ground....but in reality it is sensor"RETURN"....so dont weigh to heavily on resistance to chassis ground...... But pin 4...should be near 0 ohms to chassis ground. Thats why the the car runs poorly....The Valve is "Floating" leaving you a Huge Vacuum leak.

Get a jumper lead, and connect pin4 to Negative battery...and retry...if that cures the issue....find the rotted ground eyelet....or ...Run your own...

 

Just about solved! I had tried grounding pin 3 yesterday with no results didn't pay attention to pin 4 till late last night and sure enough, pin 4 grounded gets the car running again with no fault codes (I think). One last question - the scanner reports no codes (reports a 0) but the check engine light is still lit, when using the scanner to clear the codes it gives and ERR or ERR2 in response at least half the time, makes me wonder if another ground is missing....

 

I got a 2005 Pacifica with a 3.5L engine. Are there any tricks to changing the EGR valve? The exhaust manifold is partially blocking access to one of the bolts attaching the EGR to the head.

 

swivel sockets

 

Thanks. I had a swivel socket on it last week but could not get the leverage I needed because of the angle of the swivel socket. Will try again this weekend with some other extensions for leverage. In attempting to loosen the bolts last week it seem like a lot of force would be needed to break the bolts loose. I stopped when I had about 40-50 ft/lbs of force on my ratchet. I don't want to break off the head of the bolt or worse... strip the aluminum head. Have you seen problems with the bolts seizing and breaking?

 

Follow up from previous post. Got the valve off and reinstalled. Removed some parts (like the heater hose for better access. Used swivel socket and ratchet positioned deep in engine bay for leverage needed. Also replace camshaft rear cover plate O-ring while I was there. Engine light now off, everything running fine.