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isx cm871 overspooling - Printable Version

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RE: isx cm871 overspooling - Rawze - 09-05-2018

(09-04-2018 )Crash Dummy Wrote:  ...
ugh, was afraid you would say that! My Mechanic doesn't do the programming, he has some guy online do it from a remote, which i didnt know till just recently.
just wish i had found you before i jumped off into it. As hard as times had gotten, just couldnt see throwin another 10k in filters and docs at it in so short a time between them.

I added this thread to the "bad delete collection" ...
http://rawze.com/forums/showthread.php?tid=1558&pid=13255#pid13255

The only people who have repeating turbo problems are those who have bad delete programs, those who have purchased turbocharger parts on-line from chineese sellers, those who have Chinese fake turbo's, or those who use those el-cheapo egr-cooler block plates in the exhaust off the Internet that eventually break apart and go through the turbo.

A decent de-mandate does not suppress the fault codes for turbo over-spool or excess exhaust pressures (sounds like your ecm is blocked from reporting those fault codes). It also will not over-spool or over-boost. The CM871 only needs about 36-37 psi boost maximum for achieving up to 600HP without the EGR active, as it is running on only clean air into the cylinders. Newer model engines need even less as they have higher compression ratios. This is a far cry away from causing turbo over-spin, or any other type of risk to damage even if you had NO exhaust piping on the back side of it.

Typical turbocharger lifespan on them is 400 - 600k miles or more, proper demandating does not shorten their lifespan, but instead extends it a bit due to lower soot levels when it's done right.

As that model engine reaches roughly 40 psi boost, you are getting into the zone of excess detonation and creating a lot of internal friction (results in higher than normal oil temps). I have seen plenty of guys loose engines unpredictably at 40+ psi. Everything from fretted out liners (resulting in blown head gasket) to holes through the tops of the pistons.

-- The saddest part in all this "bad delete" crap I see over and over, a hundred times a year is that FOR SEVERAL YEARS NOW,.. I HAVE OFFERED FOR FREE to help ANYONE who is doing that type of ecu work. I give advice towards proper engine combustion theory, engine settings, + discussion of what is safe for them, not so safe, and so on. This is because I got totally sick of seeing truck after truck with exactly the problems you now are facing. -- However, helping others for free has only resulted in these narcissistic dick*head arrogant a-holes that do such work, instead of using that resource, hating my forum and what I do because I also educate truck owners themselves in the same ways with regard to proper method. They hate me because it ultimately reveals how bad their brain-butchered work really is.

Auto tuning forums hate my guts pretty badly because of this and like to pick on/pick apart everything I say even though what i do is for free. It is because most of them are only interested in boosting their own blind arrogance and pushing their crap onto others for a quick dollar vs doing a proper thorough job for what they are being paid. - Any fool with a laptop and some pirated software can over-night suddenly become an expert custom ecu tuner and it is a plague in the trucking industry how many dumbarsses there are out there with their golden screwdrivers. Some have done it for so many years now that they have convinced themselves through sheer arrogance that they know what they are doing and there is no telling them otherwise.

For those who don't know any better,.. the truck owners,.. they are the ones to always suffer the fate of this arrogance and ignorance in the end simply because there is just too many false promises and convincing testimony of "well my friend had it done and likes it" or "this guy said they are good at it" out there by these custom tuning morons to keep their steady supply of victims going. - It is sheer exploitation of the guy who is desperate and having repeating DPF problems they prey upon, simply put, and I get sick in my stomach every time someone new joins this forum and has a story just like yours to tell.


RE: isx cm871 overspooling - Brock - 09-05-2018

Have you pressure tested your entire charge air system? Not just the CAC....... Have you driven the truck with insite connected to verify turbo speed?


RE: isx cm871 overspooling - Crash Dummy - 09-15-2018

After all is said and done, ECM Programming had become corrupted, would not show faults of Turbo, no overspeed, or some other faults, dont ask me how, but this is what i was told. ECM off and Total Wipe, and reprogram. ECM then showed fault of ecm rpm at 150000 when engine was off,this after a test drive, as no faults were seen prior to removal. replaced speed sensor, same effect, different ecm showed same, so, we did some tracing of the harness, seems the speed sensor harness had broken. Replaced harness, and now speed sensor works correctly. My thoughts are someone wasn't paying enough attention when removing head for repairs and separated the harness wiring. We shall see, seems this isn't the first de-mandate performed by the shop I use, but has been the only one that developed the turbo destruction phase, so all were caught scratching heads.
It has been a very long ordeal, hopefully it all is fixed, as I stated before, after demandate, truck performed as it should have for a year, my thought is, if it had been a bad de mandate, I should have seen trouble long before a full year had passed, and the head gasket or turbo blowing much sooner.
Even the pre mandate engines would blow head gaskets, As I have had one i owned before do so, And when I wrenched in years previous. So, that said, A bad delete in my opinion should show its bad side much sooner than what I have experienced.
I do appreciate all the responses i have gotten from those here, and shall continue my pursuit of learning more of the way this engine does what it does here.


RE: isx cm871 overspooling - Rawze - 09-15-2018

(09-15-2018 )Crash Dummy Wrote:  After all is said and done, ECM Programming had become corrupted, would not show faults of Turbo, no overspeed, or some other faults, dont ask me how, but this is what i was told. ECM off and Total Wipe, and reprogram. ECM then showed fault of ecm rpm at 150000 when engine was off,this after a test drive, as no faults were seen prior to removal. replaced speed sensor, same effect, different ecm showed same, so, we did some tracing of the harness, seems the speed sensor harness had broken. Replaced harness, and now speed sensor works correctly. My thoughts are someone wasn't paying enough attention when removing head for repairs and separated the harness wiring. We shall see, seems this isn't the first de-mandate performed by the shop I use, but has been the only one that developed the turbo destruction phase, so all were caught scratching heads.
It has been a very long ordeal, hopefully it all is fixed, as I stated before, after demandate, truck performed as it should have for a year, my thought is, if it had been a bad de mandate, I should have seen trouble long before a full year had passed, and the head gasket or turbo blowing much sooner.
Even the pre mandate engines would blow head gaskets, As I have had one i owned before do so, And when I wrenched in years previous. So, that said, A bad delete in my opinion should show its bad side much sooner than what I have experienced.
I do appreciate all the responses i have gotten from those here, and shall continue my pursuit of learning more of the way this engine does what it does here.

Don't fool yourself!. Pull a copy of that program out of that thing, e-mail it to me, and I will inspect the programming for you to see if it looks half decent. Its your $36,000 engine and trucking career you are gambling with there. I have seen people that have run around as blindly as you are right now fooling themselves into thinking the same exact things you just stated only to find out later the hard way they should not have had such blind faith. when someone works on my truck,.. I INPSECT THE WORK TO ENSURE THE JOB THEY DID WAS DONE RIGHT AND NOTHING WAS DONE WRONG!. This is even if i had them do something as simple as change out a tire or U-joint. Treat what someone did inside the engines computer the same way, especially knowing that one small mistake or oversight WILL EVENTUALLY LEAD TO ENGINE DAMAGE!.

Anything LESS and your are only fooling yourself with and taking a blind faithed gamble with your engine, your truck, and your trucking carer!


Does that thing have a boost and pyro gauge in it? -- If not, then you should install them ASAP as well so that you can monitor your boost pressures and pyro to ensure everything is at least "in the ballpark" for that engine and also to help you save fuel / keep an eye on EXACTLY THE PROBLEMS you have been dealing with.

e-mail me the program out of it,.. I will make a report based on what is in it,.. then post it here as a follow-up if you like. Its your truck., at the very least, you should get a second professional, especially considering that the odds are against you greatly when it comes to ECM programming matters.

"You can lead the thirsty horse to water, but if he decides to eat the sand in front of the horse-trough instead, all you can do is shake your head" -- Rawze.