Where on the vehicle do i find the engine option code to determine the correct egr valve for a 2005 3.8L grand caravan

Without knowing what the actual code is, I can only give you general info.
No trouble code tells the mechanic what the problem is. Only what to test or check. So O'Reilly was wrong if they said the code told them the injectors were clogged. And AutoZone was not right in saying the sensor is bad, the sensor MAY be bad.
The trouble codes direct the mechanic as to what to check by saying the sensor is not sending the right data or signal, or the computer can not control a component correctly. In your case, the EGR sensor measures pressure and flow for the EGR valve. The valve may be faulty, or the sensor, or a hose in between.
So the EGR system would need to be checked out to determine if a component needs to be replaced or not.

Replace the EGR valve. Very common code.

P0405 is an Exhaust Gas Recirculation fault. This could be a faulty valve. You could try cleaning the valve first, chances are it will need to be replaced in the long run. Hope this helps...

I would clear the code and see if it returns. If the EGR valve is stuck open, it would make it buck or shutter. If the EGR valve is not functioning right, or clogged up, it will effect proformance. I would replace the EGR valve. I read that it's a common problem.

p0404 is-egr flow ckt range/performance, check egr, remove from vehicle and clean out carbon from valve and where it mounts on engine. also check the wireing connector and wire to valve. if this dosnt work, replace valve,

check egr valve, remove it and check for carbon at engine where it mounts, or end of egr valve. check all lines and hoses to egr valve. when repaired. erase code with a obd2 scanner. egr sensor -A- high input.

3.3 engines has the egr valve with transducer.you have to replace the whole unit. code p0406 what its trying to tell you your egr valve circuit is short to ground.it has failed .

it is your EGR Valve. EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve
, an actuator solenoid, and a differential pressure sensor EGR (DPFE). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 code means that OBD detected an insufficient amount of EGR.

Causes A code P0401 most likely means one or more of the following has happened:

• The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced
• There is a blockage in the EGR (tube), most likely carbon buildup
• The EGR valve is faulty
• The EGR valve may not be opening due to a lack of vaccuum

Possible Solutions In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.

• Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
• Clean out the EGR valve and/or tubing to remove deposits
• Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
• Replace the DPFE sensor (with a good quality / OEM one)
• Replace the EGR valve

LOCATION:
drivers side of the engine bay, just under the intake manifold plenum where the throttle body bolts up! If you take the air snokel off you'll see it better! It has a remote mountted vaccum solenoid with a 2 wire connector going to it that you should be able to see near the throttle body.
Follow the hose from the solenoid down to the valve and you'll find it!

hopes this helps-------lebones

I replaced the EGR Valve ($80 after tax), problem solved, vanruns great now. Now my problem is that I can't get the light to turn off.

Hi, this is my first post. I had the same problem with my 2005 Grand Caravan. Great van, but all of the sudden, the check engine light came on, and then it started driving "jerky." I found this post, along with others on the web, and diagnosed it myself. Let me outline how I did that, since this will accumulate info from several different sites:

1. I turned the ignition key from the "on" to the "run" position about 5 times, and a code showed up in the mileage slot. My code was P 0404, which read more like "tripP 0404".
2. I looked up that code on google, and also asked the guy at Autozone. Both said it was a bad EGR valve.

**Side note: there is a little thing here in the 2005 Grand Caravan called a "XZZ Option Code" in relation to the EGR valve. As in, when you go to get a new EGR valve, they are going to ask you if you need the "XZZ Option" or the "XZZ Exception." When you ask the guy at Autozone what the difference is, he doesn't know. So, after a little research, the difference is this: if your VIN has the letters "XZZ" in it, then you need the "XZZ Option." If your VIN doesn't have "XZZ" then you don't need that option. (Thanks a lot, Dodge, for that bit of stupidity.)***

3. Autozone didn't have the EGR in stock, but Federated Auto Parts (aka KOI, in our area--Cincinnati) had five in stock, so I got one--it cost me about $85.00
4. After getting home, I changed it out, in the following steps.
a. I disconnected the battery.
b. I disconnected the electrical line coming to the EGR (by the way, the EGR sits just above the alternator...and if you don't know what the alternator is, take the parts to your local mechanic and ask him to change it out for you...)
c. I disconnected the vacuum line that comes into the top of the EGR, as well as disconnecting the other end of that line, just to get it out of the way. That took 4 bolts, and they were 8 mm.
d. I removed the two bolts (10mm) holding the EGR in place, and they were a bit tight to get to. I would suggest a 1/4" drive U-joint to get to the bottom one, but a two inch extension held just right will get the job done--I didn't have the u-joint for my socket so it can be done without it...not much fun though.)
e. I replaced the metal gasket (it came in the box with the new EGR), and reversed the steps to put everything back together.

After restarting and test driving the minivan, I have no check engine light, and the "shuttering" is gone. I'm about to drive to Texas next week...we'll see if it solved the problem. More news later.

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