CM870

[ynot]

I know this is an old thread but for anyone that stumbles upon this in the future it may help them.

The truck is derating from the compressor outlet temps getting outta range, too high in other words. So its cutting back the fuel leading too lower boost too get the temperature estimates back in line.

The problem is the ecm can't estimate the COT anymore using the CIT, IMT an turbo efficiency tables in the ecm for the vgt while using the hx60. depending on the hx60 used a lot of them dont even have the bung too install the compressor inlet temp sensor so tuners just disable it an lock the CIT temp at a global valve of like 70F, which compounds the problem further when I the ECM trying too estimate the COT based off the CIT of 70F.

Installing the compressor inlet temp senior in the intake piping as close too the turbo as possible helps but the derate will still happen occasionally, really the limits on the COT derate need too be increased, or the derate just turned off.

EDIT:

I just noticed the type of turbo wasn't mentioned so it most definitely doesn't have the compressor inlet sensor, too help with the COT calculations.