Hi i got a 1997 ford f250 with 7.3 turbo and it all the sudden started starting hard so i thought bad glow plug had a few bad ones so i replaced them all and it still starts hard and smokes and when its cold it make a thumping sound and dont have power until its warm or at a higher rpms at low rpms it makes the sound what could this be?

 

Is it a sucking/blowing sound ?

 

Is the glow plug relay working? Mine would click but it still wasn't working. I replaced it and all is well.

 

Injector Orings perhaps?

 

Could it be the EBPV? Maybe not with the thumping sound though.

 

In my opinion i think its a injector just the way it acts and i haven't checked relay my biggest thing is why the sound is there

 

If your glow plug system isn't working like it should be these things will really hammer and knock until they get a little heat in the engine. I;m guessing that's what you're hearing.

 

I tested my relay and its working fine. I ran a test with my scanner and it said an exhaust valve

 

Exhaust valve or EBPV? Never heard of a scanner that said exhaust valve is bad.

 

Wats a EBPV????

 

EBPV is Exhaust Back Pressure Valve. It's a butterfly valve on the outlet side of the turbo that is intended to close partially to aid in cold engine warmup. The engine can run just fine without it and a lot of people unhook it. The sensor for it tends to fail and then it closes when it shouldn't and impedes engine performance.

 

I bet u that's wat it is i had an exhaust leak that i got fixed ill dig into it thank you

 

There is a two wire connector under the intake side of the turbo. If you unhook that it should disable the system.

 

Ok ill do that