I have a truck with cm870 all original set at 475.Truck started to surge under acceleration. It throws no codes however if you disconnect the egr it runs fine in a silent derate. Ran turbo egr test and all pass . Replaced fuel filters no change. Checked fins/actuator on tubo all good. Just put a new egr valve on it and same thing. Egr cooler not leaking....any other ideas?
do an EGR tune-up.. replacing the Delta-P sensor (and clean out the crossover tubes for it) + replace any other sensors that are old on the intake side of the engine.
also be sure to replace the exhaust back-pressure sensor and clean out its circuit thru the thermostat housing too.
(02-15-2022 )Rawze Wrote: [ -> ]do an EGR tune-up.. replacing the Delta-P sensor (and clean out the crossover tubes for it) + replace any other sensors that are old on the intake side of the engine.
also be sure to replace the exhaust back-pressure sensor and clean out its circuit thru the thermostat housing too.
Will do. Thanks
Great advice as always. Needing to do mine as preventative maintenance as well.
(02-16-2022 )Luckyjayb Wrote: [ -> ]Great advice as always. Needing to do mine as preventative maintenance as well.
it is a good place to start... but those CM870 can also start surging like that when the (air operated) turbo controller starts going bad too. - It is cheaper however to do a tune-up and cover the basics before starting to replace more expensive things is all.
I tore it apart yesterday and the one delta p line was plugged solid. Cleaned it all out and she's running like a champ. Appreciate the advice.