+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: Ask Your question... (/forumdisplay.php?fid=45)
+--- Thread: Cm870 all stock surge (/showthread.php?tid=8047)
Cm870 all stock surge - Hambone - 02-15-2022
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?
RE: Cm870 all stock surge - Rawze - 02-15-2022
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.
RE: Cm870 all stock surge - Hambone - 02-15-2022
(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.Will do. Thanks
also be sure to replace the exhaust back-pressure sensor and clean out its circuit thru the thermostat housing too.
RE: Cm870 all stock surge - Luckyjayb - 02-16-2022
Great advice as always. Needing to do mine as preventative maintenance as well.
RE: Cm870 all stock surge - Rawze - 02-16-2022
(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.
RE: Cm870 all stock surge - Hambone - 02-16-2022
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.