Studder at half throttle followed by smoke (Video inside)

[BassMedic]

Ok so I bought an 2000 e450 ambulance with a 7.3L power stroke. Ran fine on the 2 hour drive home, parked it in my driveway. Have started it every week or so to keep everything moving while it awaits my upcoming build.

Here's a video of my issue:

You Tube

You Tube

Starts and idles fine, no smoke. About half throttle it stutters and then turbo starts spooling, immediately followed by white smoke. White smoke smells like raw diesel, not sweet.

This is going to sound extremely dumb but when the vans off and you push the pedal to the floor it feels soft at first then it feels like its hard at half throttle (where the problem starts when engine is running) almost like a second cable is engaged at half throttle. Is there some sort of valve or something thats supposed to open at half throttle?

This is my first diesel, I know a little about the basics of a diesel (not looking for sparkplugs lol) but then throw a turbocharger in the equation and im bamboozled.

Any help is appreciated

[atvrider93]

well the throttle is completely electronic so there's no valve. Where in the RPMs does this happen? Is it at all intermittent?

[BassMedic]

Thanks for the info on the throttle. Not at all intermittent, happens every time. I don't have a tach but i do have an electronic pto box that reads rpms. Ill check it tomorrow

[Ford rockz]

You didn't lose a boot going to the intercooler, I had a very similar problem my 02 would dog out at 2000 rpm, without the intercooler hooked up it couldn't produce boost. Just check that the aluminum tubing is hooked up, they have rubber couplings and hose clamps..

[BassMedic]

Originally Posted by Ford rockz

You didn't lose a boot going to the intercooler, I had a very similar problem my 02 would dog out at 2000 rpm, without the intercooler hooked up it couldn't produce boost. Just check that the aluminum tubing is hooked up, they have rubber couplings and hose clamps..

Well with it being an e450 I'm pretty sure it doesn't have an intercooler But I will check for leaks on the intake and such.

[BassMedic]

Ok so i found out this issue starts at 1800 rpm after 1800 rpm it starts smoking

[BassMedic]

Turned out to be moisture in the fuel from sitting, added some power service diesel kleen and about 5 gallons of fuel and it seemed to sort the issue out. Having a few other issues but I'll get those figured out in time.