Now I read on a couple pages about unplugging your MAP sensor in your 7.3 to "roll coal". While I'm not new to diesels, I am new to reading about such a thing. I had nothing to do after work today so I figured I would do it in my driveway just to see what really happens. I read multiple things such as, your truck will dump soot, your truck will go into limp mode, your truck will de-fuel and die out, you will lose power, you will gain power, and you'll only get the soot if you have manual transmission to lug it out, your truck will run like garbage, you'll get soot at really high RPM only, and that it'll just throw a CEL (which is a given, clearly). So anyway, I did it, unplugged it and started the truck, I immediately did of course get the CEL, no difference in my motor ideling, and I just stepped on it once before shutting down and a very thing "poof" of smoke came out. So I shut the truck down and went back inside, completely forgot to plug it back in and went to the store later on and drove halfway there until I realized it was still unplugged, so to add to that, with driving (I do have a ZF-5), I typically lug out taking off and going from 2-3rd gear, no smoke, and there was no smoke at my high RPMs from 3-4 ,4-5th. So I then pulled over and plugged it back in and continued on my errands. I do not by any means want to roll coal, and look like an ***hole, I'm just curious if anyone has ever done this, and successfully "accomplished" that they wanted to soot, or if had the same results as me, which was nothing. Sorry for the long story guys! Lol

 

Why????? Why even ask??? Just my .02

 

What Adam said. This is a question not even worth discussing. I'll even be really honest and say what a dip**** question, but maybe someone will know and enlighten you. Diesel truck owners are already having a hard enough time with people that don't like us and people doing this kind of idiocy certainly don't help.

 

Its really that much of a problem to ask to ask a question around here, ****, now I remember why I stopped coming on this forum years ago..

 

The question can be answered by the fact that the PCM will default to what it guesses it should be seeing from the MAP. This is a good forum agnhfd, I left all others because of what you 'think' your seeing here. There are a bunch of great guys here!

 

Well, it would be my guess that if you were on this forum years ago, you would already know what kind of response you would get to a question like this. I'll try to be a little nicer this time so your feelings won't be hurt. If you ask about rolling coal, You will most likely get the same kind of response from most on here because rolling coal makes us all look bad. There. Is that better? The subject has been beat to death with the same type of negative response. If you did a search on rolling coal, you would probably see exactly what I'm talking about. And Glenn is right... There are a bunch of great guys on here, but that doesn't mean we don't get annoyed from time to time with some pretty silly questions. We're just human. Anyways, happy trails.

 

https://www.ford-trucks.com/forums/1...e-offense.html


read up on this thread please

 

Wow, I read that thread and it worries me. No matter how hard I try there are times when I'll 'blow smoke'. Especially taking off from a stop, if I don't ease into it to get the R's up I'll dump black. I don't like it, its embarrassing!

 

Well Glenn, I think it's one thing to blow a little smoke from heavy hauling, but to roll coal like a sled puller or race truck is just silly. I am guessing you are more than fine.

 

I wouldn't worry about it Glenn. That kid was asking the cop for attention; he just got more than he wanted.

 

Glenn, it's OK to roll some smoke when hauling heavy, especially from a stop. Look at the big rigs at truck stops. They all do it if diesel.

OP, to answer your question, NO, unplugging the MAP sensor will not roll coal unless the engine has some other serious issues. You need more fuel which will require larger injectors, turbo and a tuner supporting those modifications.

 

Removing the map sensor is also a great way to find out if ur transmission is going out. I removed mine a while back to narrow down a bad sensor issue. It advances the timing and runs like a stripped ape. But the transmission shifts so hard and fast it'll grenade a weaker transmission quick. My transmission was brand new and rated for 700hp, so it held up to those hard shifts. But where talking about a 10mins period that this was happening. It felt like I got rear ended at 30mph everytime it shifted. In conclusion it's a horrible idea, and mine didn't roll that much coal with it. Might have actually rolled less coal. Stop trying to turn your truck into a BRODOZER. IT gives diesels a bad name.

 

Never heard of the MAP sensor doing that. I've had mine on the 97 disconnected a few times and it runs and shifts just fine. But, if the Barro sensor is unplugged or bad then yes, it will affect the transmission shifting.

 

Ha your absolutely right. I saw MAP and thought of how my Barro reacted because I did it around the same time. Thanks for the correction sir

 

Baro sensor is built into the PCM board from memory. There is no dedicated BARO sensor on the truck, eg in the engine bay.
Easy way to check this issue would be take red line off and plug it. Run like that and see.. if that red line isn't connected it cant pull the waste gate and blow off the turbo pressure. If the truck runs fine without it then it's possible the MAP sensor is reading wrong , causing the waste gate to open early.
If the truck still runs the same way you have a boost leak somewhere, which IMO it probably is. Check all the boots and see if they are tight and not split.
Check to see if they lined the turbo up properly too, both sides.