550 5eK Cat smoking/missing in cold temperatures.

We took the truck for a bit to break it in right. Cool startup it catches right away buy billows smoke until it gets some he in it. It also was stumbling/coughing around 1500rpm.

Shop took it back, tore it down again. Coughing find anything but got new rings and honed the liners again. They're going to put a new cam position sensor in and see if that does anything.

So far it has

Full inframe with interstate mcbee
New head
New dampener
New 58 injectors
New cam
New fuel pump
New fuel plumbing
New injector harnesses

Tried 2 ecms, multiple timing calibrations plus meter timed. Overhead done and checked 3 times. Cylinder cut out test runs on every cylinder. Fuel pressure checked steady no dips or drops. No codes on ecm and all parameters reading correctly. This is nuts.

When pulling a load has decent power and runs not bad. Has a 550 brakesaver tune, steadspeed manifold and 78mm/1.45 borg. Was pulling less egts post rebuild. Boost was good.

But still on a cool morning it still smokes out the yard until warm. It certainly seems it's over fueling when cold.

 

They did the timing sensor again, which apparently helped. New issue is it was running good until he turned on the jakes. It then wouldn't disengage the jakes until he shut the truck off and restarted. Then it would run fine until he hit the jakes again.

He got a test ecm. He installed it and everything went to crap. Now it barely runs on the test ecu if at all. Stock 550 5ek tune which is what the engine ar is. We're all pulling our hair on this one. Still no codes on any of the 3 ecms we've tried, parameters are reading correct values.

Cat is of no help since it's an aftermarket kit which I'm not surprised. Most guys are blaming injectors although cut tests show it's not isolated to any singular/group of holes. A good dependable truck that went in with a bad hole has turned into a nightmare.

 

On cold starts is white/fuel pretty sure. I haven't been around it recently when it's running like total crap. I'll bring up the solenoid o ring. That would make it run like crap and not likely throw a code.

@pnw guy what issues did you have with Mcbee? Never used them before but this shop used them quite a bit with no issues till now apparently. They did warranty new parts when they tore it down after the rebuild. They seem interested as well what could be happening.