Suggestions on sudden power loss???

[SCHOOL BUS]

Lost 200hp in a weeks time. Same Dyno. Made 6 passes at the track between each Dyno. We were thinking it might be head gasket. Compression test showed everything I great.

What now?
Maybe it jumped timing?
My afc housing was pretty loose, almost falling off. Could that have messed with rack travel?


Feel free to throw things out there

 

[WUnderwood]

what does Chris S. think?

 

[SCHOOL BUS]

He's gonna start checking different things Monday morning. He says he hasn't seen one do that before without the problem being pretty obvious.

The truck still runs great just short 200 hp on fuel.

 

[NickTF]

Fuel supply look good? Any abnormal motor sounds? Hurt the trans? You know, all the good ole culprits

 

[SCHOOL BUS]

Yea everything looks, sounds and runs good.


Idk

 

[estrada5.9]

Does the FSO arm have a key?

Could have slipped with out a key

 

[jlibert]

does it feel like it's down 200hp?

 

[SCHOOL BUS]

Well I made a few Dyno pulls @ 900 on spray and 720 on fuelloaded on the trailer. Took it to the Nhrda race made was having blown boot issues all day so got one full pass in on my last run and didn't run like it gained 200hp. Loaded it on the trailer took it back to Dyno and did 700 on spray 500 on fuel.

So I don't know if what's wrong happened on my first pass?

 

[captain_stabbin]

is the afc gutted?

 

[SCHOOL BUS]

Yes

 

[silvercummins14]

hurt turbo?

 

[Snedge]

Do you feel a power loss ?

 

[SCHOOL BUS]

Not really but it could have messed up on last Dyno run or first pass at tge track. All of my trap speeds from the track show around 700hp on hp calculators.

 

[SCHOOL BUS]

Not really but it could have messed up on last Dyno run or first pass at tge track. All of my trap speeds from the track show around 700hp on hp calculators.

 

[impmouse]

waste gate stuck open?

 

[VMAX]

Hmmm Check your fuel pressure maybe?

 

[Lostnwalmart]

Fear!

 

[jlibert]

does it feel like it's down 200hp?

Do you feel a power loss ?

Not really but it could have messed up on last Dyno run or first pass at tge track. All of my trap speeds from the track show around 700hp on hp calculators.

You'd definitely feel 200hp. If it was 50hp or so, I could understand not being able to tell. No way you'd trap consistently if you were down 200.
I'd go back and re-dyno before you go tearing into it.

 

[BgBlDodge]

Check the timing.

 

[SCHOOL BUS]

I havnt been down the track with 900. Last time out I was at 600. Run 11.3.

Dynoed 897. Loaded on trailer. Brought to track. First couple of passes I was fighting blown boots. Got one good pass in and ran 11.0


Damn near 300 hp jump doesn't give you 3 tenths. So I'm assuming something happened in those first couple of passes or maybe on the last Dyno pull. Idk. I'll check out all the suggestions. Thanks guys