I have a 2003 f35o 6.0 with 160000 kms on it..While pulling my 5th wheel the truck will give this cough or turbo fart(as I call it) and when this happens puffs of black smoke come out tailpipe..this happen for 5 to 10 seconds I ease off on throttle and then it clears up..may not do it for a long time or that day..does it on flat or hills..Just changed fuel filters and use ford additive in fuel..when it doesn't buck cough or fart truck works fine..does not do it unless pulling the 5th wheel..can anyone give me some idea whats going on...is it the turbo,injector ?? with thanks for replies ..winemaker

 

You need to clean your EGR valve and/or turbo. Also wouldn't hurt to code scan the truck to see if it has any stored codes that won't throw a CEL.

 

My turbo only farts immediately after letting off the throttle and it happens only for a split second. I don't notice any smoke.

I'm guessing you have something else going on.

 

Yes, under load turbo fart, or coughing as I call it is either EGR or variable geometry turbo sticking. Mine does it towing trailer, usually when it should be shifting down, get black smoke and chugging, see my other thread. I am going to try the EGR first. I have been monitoring for codes, so far still none.