So when I nail the pedal I get a bad miss around 1900 rpms. If it was timing would it do it throughout the rpm range? This is on my 94 in my signature. Schwitzer turbo (tiny one). Maybe its starving for air.

 

I would think timing would do it throughout at least a larger RPM range.


Does it do it loaded going down the road as well as just holding it at 1900?

 

Whens the last time you changed the fuel filter?

 

If I ease into it it wont do it. Just when I stab the pedal.




the fuel filter is old but doesn't have many miles on it. I havent been driving this thing.


I checked fore and aft play on the turbo and I would say its out of spec. Its not blowing oil into the intake yet though.

 

The filter doesn't have to have a lot of miles on it to be plugged one bad tank of fuel and you are there.

Also if you haven't been driving it then you have a good chance of having Microbiological contamination...a form of fungus grows in it under the right conditions (slimy bacteria) and it plugs things up.

As cheap as a filter is I would look there first....old fuel is a real issue in these trucks.

 

Will do. I had Power Service in the tank. I dont know if that prevents microbes from forming?

 

No they make specific products for that "Power Service" has one called "Bio Kleen Diesel Fuel Biocide" I use it in my 96 that sits a lot to keep it from going bad...so far so good (knock on wood)

Condensation forms in the tank each time it heats up and cools off in the summer months causing water in the fuel that algae loves to grow in...a full tank will actually sweat less condensation inside than a partial tank will.

 

I have a bad over flow valve that will not hold the right pressure at the pump, make skipping, white smoke and missing.
Easy to diagnose, just clamp [lightly] the rubber return line behind the fuel filter with a Vise grip, and rev the motor.
If it runs better replace the OFV.
Don't leave the vise grips on any longer than you need to to diagnose.

 

I'll have to run it up to 1900 + rpms while thats pinched. Is that safe? I thought there were some seals in the IP that could be damaged from high pressure?

 

A lightly pinched return line for a few seconds to diagnose should be safe.
The lift pump will only supply so much PSI, it is the fuel that cools the injection pump that you want to keep flowing back to the tank.
You would not want to close off the return line for long periods, due to the lack of cooling and lubrication.