Just Went from being a long time gas pedalled to a newbie with a diesel. I am getting quite an education. This is my first one, a '97 7.3 with 150K on it. Got it to pull a big boat. It has gotten me back and forth to the Florida Keys twice but each time would only get up to 55mph before starting to overheat. So far, I havemade the following upgrades to help this. First, added a cold air intake and the running temp went down. added Rev-X and improved the running / idle a lot. Just added a fuel chip and that seems to give me more HP and torque. Finally, I just added a 4in exhaust. It ran much better but after about 100 miles is running way cold, using more diesel and tends to run great to the store (about 15 miles only to not start at all when I came back out to start it. eventually, it started and ran fine but has since done that again....didn't even get the boat out of the driveway. Again after cranking for a good while it started back up. now it seems to be running much better after changing the oil surprized it took 13 quarts of Rotella T. I also added a new fuel filter. Once I started it back up though, it is now blowing tons of white smoke which soon turns blue and then black once it warms up. Seems like the oil change did it a lot of good in the power dept but I am concerned something else may be wrong. Most all of the EGR stuff had already been deleted. Why would it run so much colder just by adding 4 in pipe? Also, the EBP vsalve has been disconnected and I think it already was before I put on the new downpipe....could it have been knocked off inadvertently and that cause an issue?

 

get it to a reputable shop, do not drive it! it could have an injector hung open and if you run it the engine could fail.

 

So that can happen just from changing the oil and fuel filter? I was thinking that maybe there was air in the system or something. Can a code reader be used on a '97?

 

Power struck is right. You need to get that thing looked at by someone who has experience with powerstrokes. Those symptoms you described are all over the place. none of the upgrades you have done to the truck will solve an overheating issue either, these trucks actually run notoriously cooler than they were designed to because of the thermostats opening too soon (unless there is an issue with the cooling system). If you do have an injector stuck open it could damage your engine. better to be safe and get it looked at, new or rebuilt motor will cost you 5k or more. Get it running properly and it will last forever

 

Ok...so the oil was reading high over full this am....I drained out 2 quarts and now it is right at the full mark....started it up and no smoke except a little black puff when reving it...is a '97 too old to use a code reader on it? says it is DB2 exempt...

 

Not all scanners cover the 7.3, AutoEnginuity seems to be the favorite, I have an old Snap -On MT2500

 

Just had a good diesel mechanic look at it. Passed all of the electrical tests and all of the buzz tests but actually threw a code on all 8 injectors? how is that possible with the truck seeming running good but still smoking? He suggested that the smoke definitely smelled from unburned diesel. So now I need to run a compression test and if good, have all of the injectors re ringed and tested. Thoughts? THe smoke and a little rough at idle is the only issue I see. I am considering adding rev-x again as that definitely smoothed out the idle issue before. Could I have injectors sticking a little when no rev-x is in it? OR perhaps it is just best to follow his advice....pretty nice guy who has worked on Ford diesels for many years....I slipped him $40 bucks for his time and running the diagnostics....