RE:CM 870 EGR TUNE UP GUIDE

[madcash2]

(06-28-2017 )Nilao Wrote:  Fire up insite and open up the data monitoring tab. There should be a listing for poor fuel mileage. I would grab a buddy (or just graph and record the drive) and go for a spin. See how all the data looks. It's possible the turbo is not closing property as it's a air pressure controlled VGT. unless I'm mistaken there are no codes if the turbo becomes stuck as the only thing monitored on it is the air supply solenoid. I believe to test the VGT nozzle ring for proper operation is as simple as taking the air line off the turbo and hitting the piston with shop air. I'm not sure the max pressure you can use on a 870. That you'll have to look up in quickserve.

You mentioned cleaning the sensors. Did you clean or replace the imap and exhaust back pressure sensors? Those should not be cleaned but replaced as the passages are too small to get the soot out without pushing some farther into the sensor.

Just a few thought I had while sitting here in a door getting unloaded.

Thanks for the above will give it a go.

have a look at this screen shot. https://www.dropbox.com/s/0tcffz7zero6js...w.jpg?dl=0

the engine coolant temperature during my check shows the lowest temp recorded - 17.8 how ever i from the time i start the truck its been on 50 degrees C upwards as she warmed up.

I read somewhere that when the ECM gets wrong information about coolant temp it throws more fuel into the engine to warm up???