CM 870 JAKE BRAKES

[Rawze]

-- Your post implies that someone has made a mess of things because they did not know what they were doing.


* it only takes 2 solenoids to get all 3 stages.

Some of the very older CM870's had the 3 solenoid setup but not all of them... hence there are some factory ecm programs that are meant to drive 3 solenoids.

It sounds to me however that in your case, that you have the newer style of head and jake brake setup,... but the wrong program in the engine ECM.

PUT everything according to the engine ser# as per quickserv.com (including the exact program that is needed for that ser# engine) and there will be no more issues.

Also.. is this engine de-mandated? (deleted)?... and also does it still have its origional VGT turbo on it?.. because the VGT turbo itself IS USED AS tHE 3RD STAGE for the JAKE BRAKE!.