2016 F350DRW. 85000 miles. Meticulous maintenance, all on schedule and a lot of it before the scheduled date. All FoMoCo fluids and filters. This truck is run everyday, it's my hotshot truck. I go through about 70 gallons of fuel a day. About 4 months ago I noticed a low boost issue, just under 20 psi and slow to get there, and of course low power. This was very random with no CEL's. I used a certain QT and Kroger for fuel depending on my route home every night and eventually stopped using the QT because it SEEMED after several fill ups in a row there the issue recurred. Fast forward 4 months, it's doing it again after I went back to the same QT a few times within a week. I ran all that fuel out and put the Kroger fuel back in. It does it much less but still an issue. So I changed the oil and Fuel filters (always factory ) a little early. It's still there but not as often. When I start the truck and take off, if the problem is there I can stop. Shut the truck down, start it right back up and the problem may be gone. But it may still be there for another restart. It may come back on the next start up, it may take 3 start ups to come back. Right now it does have a CEL, the DEF heater which came on 4 days ago. I plan on fixing that but I don't think its the boost problem. Any advice? I do all my own work, built a pretty bulletproof 6 oh with over 200k on it. You can talk technical, although I'm not claiming to know it all.

 

It may be because of the heater. Reason I say this is because for some reason the truck reads all sorts of sensors and when one reads funny the computer may do something to protect the motor. I would replace the CAC pipe because they crack and you will lose boost. I got mine here https://rudysdiesel.com/c-1389339-ac...%7Cyear%3D2015

 

Good morning. Thanks for the reply. I’m finishing up a bed delete today then I’m gonna dig into it with the dongle/ app set up and look at some readings. I don’t have an sct anymore so it’s the best I can do for now. I’ll check out the intake areas, plan in looking at the full pickup too. It’s had this random problem for 30k or so and the heater just went out. But I do agree fix the known problem first. I’m just torn between deleting the def or repairing it.

 

Cured this weekend with a DEF tank heater. Cleared the code she runs like a scalded ape again. Before changing the heater I would start the truck. Let it idle. Clear the “Pending” heater code and truck would run fine even though the permanent heater code was still there. It apparently checks randomly because it did it a few times in the middle of driving. It derated itself, check codes, the pending heater code is back, clear code- truck runs great. I did this many times to make sure it was the problem. I suppose the engineers do this to irritate you enough to get it fixed. Because it’s 100 degrees in Texas right now. I also think it’s defueling when it does this, which causes lower boost. I don’t think it’s a low boost issue on its own. It’s done this randomly long before the CEL came on. I didn’t have a dongle back then but suspect something was happening and I just didn’t know it.

 

Glad you got this fixed. Those codes that keep popping up are annoying LOL