Really? you want a diagnoses with That little info?
Come On now,,, help us out, you don't have
nearly enough specifics to expect good suggestions.
Did you do the work yourself or are you just frustrated with some repair guy who's now at a loss?
First thing is, you need to have sensor readings and a good scan for codes. Can you do that? Do you have the right equipment?
If you're gonna keep & maintain the truck yourself I strongly suggest you get access to the special scanner software you need to do it.
To retrieve most of the codes you'll need to help and even do some testing look at the FORscan Lite or TorqueApp (you add an Android device and Blue Tooth Adapter for @ $30) OR the Windoze version with a USB adapter. I like this one for BT Android -> http://www.amazon.com/BAFX-Products-34t5-Bluetooth-Android/dp/B005NLQAHS/
Just a few years ago you needed to buy a professional scan tool because our trucks need to have a scanner with a Library containing both the Ford Proprietary AND the Diesel Specific codes in it. Add to that, our trucks are Not, specifically, OBD-II so the Generic scanners the Auto Parts Stores have are of little use to us. But today there are some very good App based tools, that are close to what the pro tools do, for fraction of the cost.
How To: Super Duty Diagnosis on the Cheap! This will be a multi-part write-up, covering how to diagnose, monitor, and run tests on Ford Super Duty Trucks, focusing on the Ford 7.3L Super Duty as that is the truck that I own, but these tools work for all Super Duty Trucks. Warning: Some...
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Just on the surface, without knowing Codes or PIDs, white "smoke", is too much fuel. Take a close look at the MAP & MAT sensors, might be related to your issue.
MAP: Manifold Absolute Pressure sensor Strategy and feedback input; The PCM monitors manifold pressure to control fuel delivery in order to minimize smoke. It also optimizes injection timing for detected boost. It also monitor boost to limit fuel delivery to control maximum turbo boost. Frequency output; 111Hz=14.7psi, 130Hz=20psi, 167Hz=30psi. PID: MAP (pressure baseline 14.7psi), MAP HZ (frequency), MGP Manifold Gauge Pressure (pressure base line 0psi) turbo boost
MAT: Manifold Air Temperature sensor Strategy input; The PCM uses this signal to adjust fuel and timing.
Hey guys, I realize there are plenty of reasons the 7.3 might suddenly displaythe symptoms I've listed: White smoke rough idle engine missing while driving These engines are great when everything is going right but sometimes some of those sensors start sending info to the computer that it...
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Are you making Boost? Do you have a boost gauge? (the MAP will show boost info if you can monitor it) If not then you will have excessive fuel too.