Smoke from exhaust on accel

Mekanik · March 4, 2013

I’m working on a 2008 F350 with a 6.4L. The customer’s concern is smoke from exhaust. The smoke happens after the vehicle is warmed up on medium-hard accel. I performed EEC testing-no DTC's, fuel system test-PASS, relative compression test-cyl #3,#6 down 1%.

I checked the oil level-overfilled just over the plastic indicator when 'short-sticked' which is pretty much normal.

The coolant level is low-maybe 1/2 gallon, but the upper hose appears to be leaking a little bit.

I removed the turbo down-pipe and don't see any trace of oil in the pipe.

I noticed crust on the EGRT2, removed the sensor, found that it was covered in soot but had some moisture on it. The moisture dried in a short time and was NOT white in color.

There may have been a blue tint to the smoke; it’s hard for me to tell. I’m thinking I either have a turbocharger that’s leaking or an EGR cooler leaking. Any recommendations on how I should proceed?

Thanks in advance!

lmorris · March 4, 2013

Pull the lower CAC tube off the cooler and check how much water/oil comes out. Depending on build date there was a TSB to replace the CAC with a redesigned one. They added more baffles to prevent the oil/water making it's way to the intake. Sometimes just draining them helps.

Mekanik · March 4, 2013

Yeah, I did this too. There was hardly any oil/water in the lower CAC tube. I pressure tested the cooling system, loosened the EGR cooler nuts where the two coolers meet and I didn't see any coolant leak out. If I put a mirror to the EGRT2 hole when I was pressure testing the cooling system it did steam up the mirror, but when I started the truck there wasn’t any coolant coming out of that hole.

Mekanik · March 5, 2013

I put the truck back together and went for a road test. After three miles I got some white smoke but it completely stopped. I contacted hotline and this is what they had to say:

If there are no concerns identified with the EGR coolers, then it may indicate that there is a concern with regeneration. It is recommended to obtain the DIST_REGEN_C and DIST_REGEN_REQ to see if the vehicle is completing regenerations. If the DIST_REGEN_C is close too or above 667 miles, then it would indicate that the vehicle is not being driven in a manner to complete regeneration. This can cause the intermittent white smoke to be present. If that is the case regeneration will need to be performed so that the DIST_REGEN_C and DIST_REGEN_REQ are reset to zero.

Well my DIST_REGEN_C was 867 and my DIST_REGEN_REQ was at zero. So basically this thing isn’t able to complete regen and that’s why I’m getting intermittent smoke.