JayDee

When I picked up my truck yesterday my dealer said to make sure that the filler cap was on tight before starting the truck because there is a sensor in the cap that will indicate to the computer that there is a leak and turn on the check engine light. Has anyone found this to be true? If it is, it seams to me that you would have to shut down to take on fuel or always have a check engine light on. He also said that the truck has to set for 24 hrs. before the Check Engine light can be reset. I'm not sure what he saw on my face because he quickly said &quot;but it can be done faster&quot;. <br>So I need the straight story from you folks, the people who know. <br><br>JD

bulabula

I have filled up while shut down, and running. My check engine light is still extinguished.

Commatoze

My daughter has a Chrysler Sebring, and if you leave the cap loose, the &quot;Check Engine&quot; light will come on. Believe me, it's been to the dealer twice for that &quot;problem&quot;. : &quot;Hey buddy, you forgot to tighten the gas cap. That'll be 56 dollars&quot; :'( I don't think that happens with the diesel.<br><br>-Tom-

Fordzilla

I hope you folks don't mind some input from a Ford owner (I'm actually considering my options on the next truck)...We have the same problem on our trucks...One of our members on TheDieselStop.com discovered that the tube leading into the tank from the vapor return hose extended a few inches further down into the tank than it needed to...reaching through the hole left after removing the sending unit, he cut off most of the tube down to about an inch...The result was that he could fill his tank all but about a gallon without the foam problem...I tried it on my truck and it works like a charm...Incidentally, his handle is Maroon Harpoon (hence the &quot;Pooned&quot; reference in my sig)...Somebody here with a little time on their hands (and a near empty tank) may want to drop a Dodge tank and see if the same problem exists...Makes life a little easier at the pump...Ben

DNAT

UTAH mentioned something like this too, with his smaller ride. Us VW TDI owners use what we call the &quot;filler cap&quot; trick. In the filler pipe, there's a little clip that you can push in while filling that opens the vent line from the top of the tank and allows the diesel to defoam relatively quickly and lets about 5-6L (1.2-1.5USG) more into the tank...lets me get 1300+km (850+ mi) per tank (~60L/15.5USG) on the highway, ~65mpg(imp)/55mpg(US). Haven't taken a close look on the '03s, but there must be some kind of vent line twinned with the main filler pipe that can be temporarily vented while filling. From the sounds of the &quot;cap off = CEL&quot;, sounds like a permanent mod would have to be carefully thought out, however, to avoid nuisance lights.<br><br>FWIW<br><br>DT

RATTLINRAM

One Note about the big truck nozzle,<br> I have heard and read that if you do use the Big Truck Nozzle, Only use the first click on the trigger! Any faster and you take a chance on damaging the float on the fuel level gauge sender. I use the big truck islands whenever I get the chance and never had a problem. Just my $.02 ;D

FiverBob

Just did my first fill. Put the trigger on the first notch and let her fly. When it popped off, I let it settle, tried to put in more. It did not take another 1/10 before it was in the neck. No foam. Gauge showed quite a bit past full when I got in. <br><br>You guys had me all nervous about this. See, all that sleep I missed was not necessary. Shame on you. <br><br>Bob

JayDee

All I had to do was read the fuel cap. It says right there that the &quot;check engine&quot; light will come on if cap is not tight. :-[<br><br>Oh well, when all else fails, read the fuel cap. <br><br>JD

Hunter

You &quot;boys&quot; crack me up!<br><br>What is the mileage figures and are you SURE you see pure diesel in the neck?<br><br>My CFN fueling station is purposely sloped away from the nozzle and tank to be sure you get a &quot;full&quot; tank.<br><br>Ever seen diesel owners pull into a fuel station, get out and put a block under the tire, drive on top and start fueling? I have, many. <br><br>My station has taken that into consideration and built it in the slope of the slab. So, when I am in the area, will fill nowhere else, to make sure of a perfect fill. On the road, anything goes.<br><br>Just a purist on mileage, and it makes a whole hell of a lot of difference, where you fill, how you fill etc.<br><br>Hunter

pwabbott

JayDee, I think your dealer is blowin smoke through his ears. On gassers their is a vapor recovery system, a closed system, the fuel cap must be secure for it to work properly. On diesels there is no vapor recovery system, an open system.<br><br>Your dealer is no doubt trying to sell as many Hemi-Diesels with Spark Plugs as he can.

JayDee

I hope that this helps. I had to go out in the rain tho get this picture. <br><br>JD

Commatoze

Only a guess, but I'd say they use the same cap for both gas and diesel. Traditionally, a diesel cap would be green, not black.

DNAT

Hunter, out in the field I'd try and plunk my Huey/Bell 212's right skid onto a railroad tie (conveniently placed near the fueling point, of course) to get an extra 75-100 gals of JP-4 in the beast. ;D Great minds...eh?<br><br>Luckily, the Flying J near Kingston has a decent slope at the diesel pumps and lets me cram more #2 into my little beastie.<br><br>Since diesels don't usually have a vapour recovery system on the tank, however, I'm still a bit confused by the fuel cap=check engine light thing reported by some on the Ram. I drove my Jetta around for several weeks once (you know, using up a 1/4 tank:P) with the cap barely turned into the stand pipe...no probs. I'd especially be concerned that it would take a visit to the dealer (plus some $, I assume) to clear the light. <br><br>Cheers,<br>DT

Hunter

DNAT<br><br>Did you also have an extender on her? Maybe that is what Dodge should do, add an extender! Might look a little goofy hanging off the side of her though! <br><br>Hunter

Hunter

Ok gang, I put in 34.1 gallons tonite, 2nd fill for 17.9 MPG. Mixed driving, a lot of it bouncing around in the hills looking for Bambi.<br><br>My problem is this, my fuel gauge was less than 1/16 of a tank, no low fuel light and the overhead computer still said we had 39 miles to drive to 0, which by Dodges definition means that you still have .10% of your fuel left.<br><br>Wrong answer, 35 gallon tank, put in 34.1 gallons, that would be 9/10ths of a gallon which is a far cry from 10% of the tank left.<br><br>Have I confused the crap outta all you guys?<br><br>I think I am gonna have to have the tank gauge and low fuel light etc. checked out.<br><br>Diesel is $1.51 here in Oregon and just across the river in Washington State it is $1.41<br><br>Hunter