Cm 2250 debacle

[Rig Wrench]

Lookin for some input from anyone. At a loss at the moment. Got a CM2250 stet at 500hp in a 389 Pete. Only makes about 22 lbs of boost. Revs up through the rpm range correctly. Air intake system is leak free. Fuel pressure is good. I tried a new map sensor, new exhaust back pressure sensor, and even went as far as putting another ECM on it from a good running truck. Same result. It acts like a derate but no CE light. Engine brake works as it should producing 30-32 psi at its highest setting. I've been messin with this for 2 strait days with no luck. Any suggestions?

[Rawze]

CM2250 should peak at 36 psi. It is the CM2350 that only needs about 32-33.

Monitor the engine state parameter and see what has control of the fueling.

[Rig Wrench]

(12-10-2017 )Rawze Wrote:  CM2250 should peak at 36 psi. It is the CM2350 that only needs about 32-33.

Monitor the engine state parameter and see what has control of the fueling.

Understood.
So I grabbed my computer to take a ride and monitor it, I noticed now that its cold its gained 10-15 psi on the gage. My battery died so I couldn't monitor it. But once it got up to temp. It seemed to lay down again. I'll charge up and try again

[Rig Wrench]

Finally got my hands back on it. When monitoring, the turbo goes to 9-10%, even though its commanding 40%. Tried exhaust back pressure sensor and map sensor. It runs fine then when throttle input comes in, the turbo opens way up, even though its commanding a much more closed state? Any ideas. I have an actuator here I'm gonna try, but I'm not very confident

[Rawze]

On a properly running engine, the command and measured turbo positions will be within 1% or so of each other.

[Rig Wrench]

(02-04-2018 )Rawze Wrote:  On a properly running engine, the command and measured turbo positions will be within 1% or so of each other.

Yes, I understand that. What i meant was that when it should command 40% it drops back to under 10%, resulting in about 20psi or so of boost. Its like something is telling it to open way up. But im not sure what. At a complete loss

[Mr Hagg]

If it is comanding 40 but only doing 14 then you have a stuck actuator or stuck vgt

[JMBT]

Yes, I agree with Mr Hagg. Hook up insite and do a turbo hysteris test. You’ll find it In the ECM test tab. It will tell you if the actuator or VGT are sticky. The test will say pass or fail, but you can also pull up a data monitor window and watch commanded and actual percent closed while the test runs. Make sure you have at least 150 degree coolant BEFORE running the test though. Also be sure, if you end up swapping actuators you use the little plastic gauge to set it right and do a calibration with insite or you’ll be back in the same boat.