Hi members, I wanted to share my experiences regarding terrible fuel economy on my 2005 Dodge Dakota 4.7L V8 SLT. I bought it second hand in 2012 with about 113,000km on the clock. Shortly after purchase it was apparent that the mileage sucked. I did tests over the next 4 months and got MPGs of 11.0-12.3 MPG. The frustrating thing is the OBD never threw any codes and the truck always appeared to run just fine and had plenty of power. The only symptoms were the high fuel consumption and the smell of fuel at startup. I searched forums and collected data on what could be the problem. I changed the oxygen sensors - expensive (4sensors) and a pain in the butt to do. I checked the MAP sensor which appeared to be fine (based on voltage readings). My next course of action was to try changing the EGR valve when by chance I finally got a code. The code was P0406 - EGR Sensor "A" circuit "High". I replaced the valve and now I have MPG of 17.3 MPG - fantastic! The old valve did not look especially dirty, some forums suggest you can clean them but the time and effort to change the valve on the Dakota I think it is better to replace. Even with the right tools it took about 2 hours and a lot of swearing to get this sucker changed. It is jammed in at the back of the engine on the drivers side. Getting it out was not that bad but getting it back in was more challenging. I found two quite helpful forums on changing the egr valve they were not videos but step by step instructions. One of the links I used is here; http://wiki.answers.com/Q/Where_is_t...e_Dakota#page2

Turns out the egr valve was my gas mileage problem good luck solving yours!

 

I will move this to the 3rd generation Dakota sub-forum.

 

You are welcome for the write up, I did that many years back!

Glad it was able to fix your issue

 

I just changed mine last weekend - it was the first warm days we've had here since I got the CEL and code indicating it was bad. I found that if you put the pipe on loose (keep the 2 8mm bolts really loose), and then set the EGR in place with the pipe inserted into the manifold, it's relatively easy to start the 2 13mm bolts that hold the EGR onto the intake. I snugged those 2 bolts first and then the 2 8mm bolts, and finally tightened it all. It took me a couple of hours of fiddling around trying to situate the new EGR, but once I put the pipe in loose, I was able to do the install within 15 minutes.

 

The EGR took me a couple of hours, it doesn't help that have some pretty large hands. The hole back there is a pita to get around in.