Stubborn DPF sensor questions

[joshcdsi]

I finally got around to taking out my DPF and loading my Spartan tune today, but I'm having a heck of a time getting the sensor furthest to the rear out. I've soaked it with penetrating lubricant, I've used a breaker bar, everything. All I've managed to do is break a wrench and scar up the nut.

Tomorrow -- after the lube dries away -- I'm going to try to take a torch to the exhaust bung and see if that will help, but this thing is tough.

A couple of questions for the experts on the board...

1. What's that sensor do and how bad will it be for me to drive without it in?
2. If I can't get it off, does anyone know how much those things run at the dealership?

[SCUFFY828]

ive replaced alot of dpf filters , ive had to replace several of those sensors cause they wont come out , a torch wont work either , the best thing to do , is just go buy one, and the truck wil not run right without it either

[joshcdsi]

Wow...not a good result. I went through the tuning process (loading the 210 tune) and everything went well, then it told me to turn the key off for 10 seconds then start the engine. I do that, and my CEL is flashing after startup, and within about five seconds the engine starts acting funny. I don't know how to describe it other than it was jumping. Sounded like a cammed up dragster...and not in a good way. Pushing the accelerator doesn't do anything. No rev up, nothing. So I turned it off and am now trying to get a ride home!

Help!

[powerstroker67]

You CAN'T run these trucks with a bad sensor or sensor unplugged PERIOD! It does exactly that running/not running condition described above. You will have to replace the sensor,then clear the codes to get it to run again. Installing the sensor only will still not allow the truck to start. It's starting to look like a spare EGT probe(all 3 are the same #) should be carried in the glove box like a cam sensor in a 7.3, I can see this being a probelm down the road. It leaves you stuck!

[joshcdsi]

Well, after the help of some channel-locks and a big friend I got the sensor out. Installed it, reset the codes, and I am now a VERY HAPPY man. Door to door the computer read 25mpg...I know you can't trust it, but before I was at 13.5, so even if it's overestimating it's still fantastic. Highway only (about 15 miles) the computer read an average of over 27mpg. I haven't really gotten my foot into the gas too much, but I can tell the tune is very nice. Time to put my CAI back on.

[Hanging_Heels]

I was in the same exact shoes as you about a week ago, i got out the front 2 sensors fairly easy and then got to the back one, and couldnt get the damn thing to spin.... i tried everything... including pb blaster, hammer to the wrench to try to break it free, i worked it for probably about an hour and still wouldnt budge. After that i took a torch to it and heated it up and it spun right out... just take a torch to it and you'll be fine. LOL Have fun with the exhaust hangers also.

You know i was reading people were taking there dpf's off and putting in there delete pipes w/ in 30 min.... thats BS if you ask me. But whatever...

[joshcdsi]

Exhaust hangers? I just unbolted them from the frame since they were welded onto the DPF unit. I assumed that Sean's pipe didn't need hangers since it was so light and on one end you have it bolted and the other is right by a hanger.

Are people bolting up hangers on that pipe?

[laketimejv]

I unbolted my hanger also, and the pipe install took about 15 minutes. I only took out the sensor that was actually in the DPF. My programmer install didn't go so smooth though, there is some glitch making my truck not crank over. The guys at Spartan are trying to work it out for me. I'm glad to hear that yours is running so well, I can't wait to drive mine with the upgrades installed and working!

[joshcdsi]

I might have been able to pull it off in 15 min if I had an air ratchet. The top-most bolt where the DOC connects to the downpipe from the engine is so hard to get to I could only get like one click on the ratchet with every turn. Damn thing took about 15 minutes to get off, and another 5-10 min to get the replacement pipe's bolt tightened. I had more delays when it was time to actually pull the pipe out. That was a pain, but a little twisting and it came free.

My biggest problem is that I was on a creeper under the truck -- I didn't have the luxury of a lift. Overall, though, it was a pretty straight-forward job. The truck drives like I just took about 8000 pounds out of the bed. The difference is amazing.

[Gerry]

Originally Posted by laketimejv

I unbolted my hanger also, and the pipe install took about 15 minutes. I only took out the sensor that was actually in the DPF. My programmer install didn't go so smooth though, there is some glitch making my truck not crank over. The guys at Spartan are trying to work it out for me. I'm glad to hear that yours is running so well, I can't wait to drive mine with the upgrades installed and working!

You can try one thing and see if that's the problem. Go to Auto zone and rent of one of their code scanners. Take it home and scan for any trouble codes. If you see a U0073 code it's the TCM not telling the main computer what gear it's in. Clear the code and it should fire right up. I'm not saying for sure this is your issue but it happened to me when I unplugged the DD's harness and it shorted out the comm bus bar.

Gerry