dpf is gone

It sounds like it measures the exhaust the same as the intake charge. It has expected flow rates. When the rates are out of range it throws the code. What’s interesting is that it learns. I guess due to dif driving conditions and wear & tear. Do these trucks have pressure & temp sensors in the exhaust? If this is how it works, you will have to data log how it is measuring flow rates with the cat & dpf off and program new expected flow rates. The only problem is, it is expecting the dpf to eventually get clogged so that it can regen. Also no one has the equipment to do this that I know of yet.
 
I can guarantee it doesn't learn.. It has set parameters that it checks against and determines what to do next.
But yes, finding those parameters is where to start.
 
Ridemywideglide said:
I can guarantee it doesn't learn.. It has set parameters that it checks against and determines what to do next.
But yes, finding those parameters is where to start.
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Actually, I was told by my tech that it is adaptive. I have to assume that this means it does learn. When I put my dpf back on, it was seeing close to the same pressure diff as it was with it straight piped and it continued to insist that the dpf was clogged until we reset the memory. ????
DOIT, yes they do have pressure sensors fore and aft of the dpf, egt fore and aft of dpf and cat and O2 fore and aft also. Monitored to the hilt!!!!:doh:
 
DieselLady said:
Actually, I was told by my tech that it is adaptive. I have to assume that this means it does learn. When I put my dpf back on, it was seeing close to the same pressure diff as it was with it straight piped and it continued to insist that the dpf was clogged until we reset the memory. ????
DOIT, yes they do have pressure sensors fore and aft of the dpf, egt fore and aft of dpf and cat and O2 fore and aft also. Monitored to the hilt!!!!:doh:
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Well it wouldn't be the first tech didn't know his a$$ from a hole in the ground. :D

I assure you the computer in your truck does not "learn"... Calling it Adaptive is a skew of the words meaning that sounds really really good and probably helps the tech sound better when telling a woman what he doesn't know.
It's programmed with many parameters and responds to such with many output variables. This is not learning, this is programming. That chip hasn't learnt since it was burnt..
As for the rest, I don't have the chance to play as you do.. With the sensors being fore AND aft of all the green-peace goodies, I'd think "close" isn't good enough. Close only counts in horse shoes and hand grenades.
Can you get readings of the signals from the pressure and O2 sensors for and aft under driving conditions?
 
Well I normally would agree about the tech, but this guy seems pretty humble. Said he would like to learn more about the High Performance stuff and also that Chrystler doesn't tell them much as far as the diesels go. He has had to learn all that he knows pretty much on his own. I will have to beg him to attach his equipment to my truck to get the info under driving conditions so the next time I am there that is what I will do. Sorry that I couldn't be of further help.
 
I've just not met a mechanic/tech yet that was honest and upfront. Seems they all are out to seperate you from a little more money and that's about it.
If you can get him to do that, that will give you a good place to start.
 
I agree, but these guys at this dealership are all driving these trucks and most of them are modded or at least want to be too. I think this guy truely wants to learn more about them. He says he can get any thing back to stock but is so out of the loop on the HP that he has a hard time fixing stuff that goes bad on the modded trucks. Since they are helping me with no expectation of getting paid, I have a good feeling about working with them. Of course, I will always watch my back!:poke:
 
This is interesting reading up on. I think I was the first to take the brave jump to strait pipe and I could have told you what just happened. I also had the same problem when I put the dpf back on had to reset everything on the pcm with the star scan tool. As for not going into limp mode with ppe on that is all in your head. You can not fill the difference in powerloss with a programmer etc. But when you go back to stock setting it is night and day difference. I am thinking about taking mine back off for egts and fuel milage. With the loss of power from derating the motor you dont gain in power from strait piping but you egts will be alot lower and you mpg will be about 3 mpg higher. I did alot of work trying to figure out have to trick the computer but it looks like we are going to have to wait to they come out with a programmer to just turn it off like efi live, but this programming is alot more complicated then the dmaxs.
 
What were all the codes that were set with the dpf & cat removed before reinstalling ? Diesellady you say there is a o2 fore & aft. If so this would be one of the first things that causes codes. There should be a more stable and lower o2 reading after each cat. With the cats removed they will all read the same.
 
I had a total of 14 codes set but you have to remember that I unplugged the connector from the O2 module that is right on the frame rail next to where the DPF and Cat are located. I did this to insure that it would not go into regen and dump fuel out the tail pipe. I was hoping to be able to improve fuel economy but for the most part, I got worse economy. I am attributing this to the engine derate but this is only guessing on my part. I can't figure out any other reason why it would get worse economy other than that. Most codes were O2, EGT and soot accumulation codes. A lot of duplicates as I drove home from Denver like this and for a week or so around town afterward. The 2 that wouldn't go away after I reinstalled them were P2463 and P1451. the 2463 was soot accumulation and the 1451 was EGT I think. I have them all written down at home. Hope this helps.
 
There are 3 temp sensors. 1 before the cat, 1 between the cat and dpf and 1after the dpf. 2 o2 sensors before and after the cat. then 2 tubes that go into the exhaust before and after the cat, that go up to the motor to pressure sensors. Some trucks will go for a couple hundred miles with out derating some will in 20 miles. The p2463 and p1451 are active codes the rest are not active that is why you can not clear with out reseting everything with the star scan tool. I have seen a lot of codes also. If you trying remounting the o2 sensor in a different location on the frame or put baffles in the exhaust so the flow reading is different it will just throw more codes. Who ever designed this was one smart person. They do not make since on how they work. They were designed not to be fooled it seems likes.
 
I can happen it will just take lots of time. This may sound simple someone just has to figure out how to read the tables that need to be fooled. I have been logging data but can't make much sense out of anything.... yet.
 
Doit and KMK are right, you cannot put a constant voltage to the sensor. The pcm looks for certain exhaust flow rates, based on how much intake flow there is. BUT......then it also puts it into an equation based on what temps it is seeing at all the egt probes. It then determines whether the cat is plugged, the dpf is plugged, if everything is normal, OR you have removed the dpf. There is much more to it than just tricking 1 sensor. BTW don't know if you have followed any other forums(dieselady I know you have), but the H&S exhaust works flawlessly if you have a edge juice with attitude. I even blocked my egr off successfully and NEVER see over 1350 degrees, even on level 5. My intake temps went from 130-170 down to 50-80. It runs night and day better.
 
xtrm-acc said:
Doit and KMK are right, you cannot put a constant voltage to the sensor. The pcm looks for certain exhaust flow rates, based on how much intake flow there is. BUT......then it also puts it into an equation based on what temps it is seeing at all the egt probes. It then determines whether the cat is plugged, the dpf is plugged, if everything is normal, OR you have removed the dpf. There is much more to it than just tricking 1 sensor. BTW don't know if you have followed any other forums(dieselady I know you have), but the H&S exhaust works flawlessly if you have a edge juice with attitude. I even blocked my egr off successfully and NEVER see over 1350 degrees, even on level 5. My intake temps went from 130-170 down to 50-80. It runs night and day better.
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Dang!!! That is great to hear.... I got my kit on Friday and am going to install it tomorrow, as soon as I get all my other projects finished up this weekend. I was afraid to even hope that it would work that good, but now am REALLY excited to see the difference. Everything I have tried so far has not given me much of any added fuel economy. (Juice gives great power). I am convinced it is because I couldn't stop the REGEN and haven't even begun to think about the EGR. I know on my Jeep liberty blocking the EGR has made a huge diff in fuel economy. Gets 30 mpg hwy doing 70-75. I will certainly post the results of this kit as soon as I get them. AWESOME of you guys to develop this!!!:rockwoot:
 
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Results

Do you have any results for us on that DPF Delete kit?
Shane
 
BAP said:
Do you have any results for us on that DPF Delete kit?
Shane
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I did install the kit on Christmas eve. It works good. No Regen as of yet which is good, but I still don't see a hugh increase in fuel economy. My truck has had a few issues since then though and I really haven't had a chance to get it out on the road and really check the highway fuel economy on it yet. I am on my 2nd tank of fuel and need to fill it today as I am at 1/4 tank finally.
I had to take it back to my "Horsepower Friendly" dealer at first because I was getting a lot of raw fuel out of the tail pipe. We couldn't figure out why and I was afraid I had a stuck injector. We cleared the computer of codes at one point, ( don't remember exactly why, probably because we started setting codes with the star scanner hooked up and the juice unhooked) but I think what ever the issue was cleared it self up because as soon as I got home I noticed it was not spitting fuel any more, and hasn't done it since.
So I decided to delete the EGR this last weekend and got some serious surging issues, had to un block that and put the butterfly back in. I will be trying it again today and removing the batteries to see if I can clear the memory in the truck. There is no explanation for the surgeing so we are hoping it is just a cranky computer.
I guess I need to go for a good drive to see if I can get some reliable numbers pretty soon too.
I am really glad I did the dpf delete though. It sounds good and does run cooler, although with the EGR still running through the engine it isn't as cool as I would like. But the big deal for me is being able to see if there is an injector issue or not. I have heard that these injectors can stick open once in a while, and you will never know it if you are getting leaky ones if you can't see what is coming out of the exhaust. With the CAT and DPF you will never know untill you are haviing serious issues.
 
Went out and disconnected the batteries, Re blocked the EGR, Removed the Butterfly and unplugged the egr. Put it all back together and took it for a test drive and it works GREAT!!!!! With the Juice set to clear codes on start up.. I have no cel and no more soot running throught the engine. Now for some fuel economy testing. Have to go into Down Town Los Angeles on WED for some business. That should give me some real world testing. More to come.
 
So you haven't got any codes regarding the servo controlling the EGR being unplugged yet?
 
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