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+--- Thread: Cm870 low turbo boost high EGT when freezing cold (/showthread.php?tid=2915)
Cm870 low turbo boost high EGT when freezing cold - Chamberpains - 03-24-2018
I've been helping a guy out that has a problem with his Turbo cutting back to low boost and then High exhaust gas temperatures while going down the road. He operates in a very cold region of the country. In my search to help him I ran across another Forum where they posed a similar question. The initial complaint is similar to what he's complaining of, then there's a bunch of gibberish from other people then the very last post from a guy named dynamo440 seems like a very interesting answer. I'm just wondering does that Ambient Air Temperature Sensor mess with the cm870's in cold weather.
Here's the link. Im only interested in the intial complaint and the very last guys response. Is there any validity to this threads answer?
http://www.thedieselgarage.com/forums/showthread.php?t=114358
RE: Cm870 low turbo boost high EGT when freezing cold - Rawze - 03-24-2018
It has been a long while since I have had someone ask about this particular issue. I have seen the cold weather issue discussed on the CM870's in the past. There is a bug in the software for them under extreme cold conditions. I think Unilevers has the correct settings to help prevent it if I am not mistaken. I know he discussed it with me a long time ago once back in the day.
RE: Cm870 low turbo boost high EGT when freezing cold - Unilevers - 03-24-2018
its a little know fact that cummins later calibrations had a glitch in the 870's in extreme cold ambient (-20c and below). It took me awhile to sort it but if i did why the hell didnt cummins? this is still a issue in all current calibrations for 870's.
it doesnt have so much to do with ambient temp as CIT temp and the density calculations and how the Charge manager logic reacts to this by altering engine Emissions levels or CAP_EL. this in turn alters the MCF reference and boom low boost high pyro.
FIX YOUR shi#t CUMMINS!@
RE: Cm870 low turbo boost high EGT when freezing cold - Chamberpains - 03-24-2018
Unilevers, I'll PM you his screen name and some info he's sent me on the complaint. Maybe, if he decides to, he can have you fix this so it's not even an option to be causing his problem. Thanks for the answer.