CM870 Blue Haze

[Lonestar10]

Dads CM870 2007 T-600 "Stock" no tuning. 1.6mil chassis around 200k on overhaul

Truck is hazing blue real bad stinks to high heaven.

Truck is switching engine modes or something because at one moment it can be running fine then the engine skips a beat you can hear it do something with the turbo then starts to haze real bad then it might skip again and start clearing up just to skip a beat again and haze.

for how bad the blue haze smells i think its raw fuel

when running insite engine tests it throws random codes but doesnt when driving

so far
replaced his original actuators metering and timing
new engine harness
tried a known good ECM
its being pin timing checked today

any direction to go in? im out on the road so idk if hes listening to me all when i tell him to data log it with insite and see if any sensors are going wonky.

[Rawze]

does it have a boost and pyro gauge installed?-- what are they doing?

[Chamberpains]

He's still running EGR, right? Could be the valve or piping.

[Andre_The_Giant]

The fact you can“ hear something like the turbo” leads me to think the EGR is sticking. It happend to me.. It would only stick/hang up once in a blue moon. (Even after Physically cleaning it) It took a bunch of insite Egr/turbo tests to finally get it to fail a test, with a solid week of driving around with insite hooked up.

[Lonestar10]

Yeah still has EGR. The turbo almost sounds like it's chuffing at idle you hear it start to spin up just barely then it drops out then does it again. Has pyro and boost. He said pyro was cooler than normal but boost was still good.

[JimT]

Based on my recent experience, I'd have to agree that the EGR valve could be the problem. When mine was going the symptoms were lower EGT's (resulting in bad regens), turbo spooling more or less than normal and eventually the valve stuck full open and choked out the engine trying to climb a grade. My situation was probably made worse by old neglected sensors too.

[Lonestar10]

Turns out he spun a bearing in the cam idler gear knocked both cams out of time

[Signature620]

Interesting find. Did you get any pictures?

[Lonestar10]

No I'm on the road him and his mechanic found it. So getting new idler and replacing scissor gear as it damaged that as well the idler had been walking back and forth on the bearing. Got lucky I guess that gear could froze and sent valves in pistons