Hello to all, today i went to my dads shop to finish up my 5.3 to 6.0 swap, got everything bolted up with the exception of the lpp y pipe and i didnt hook up my o2 sensors.

i went to the cab and primed the fuel cranked it over and it fired to life.
the dash said Reduced engine power it was also revig high idle.
i turned the key off and the engine kept on running for about twenty seconds.

thought it may be a fluke, i started it back up... no good same thing.

is this something any body else has ever had happen?

and my gas pedal/throttle doesnt work

 

Was computer or anything changed. I have never heard of run on after the key is off (with the newer stuff unless electrical issue)...Possible ground issue. Did all grounds get bolted up?

Dustin

 

i think that the ground have been grounded, yes i had Nelson retune it for the 6.0

 

Great no one knows?
Any speculators, just want a good place to start diagnosis..
BLAKE

 

When I first bought my truck I had issues were it wouldn't start and occasionally showed the "Reduced Engine Power". They replaced everything. They fixed the problem after the truck left me stranded three times. They stated the problem as being a bad/loss fuss block(one in engine bay). Not sure it this helps. I know it's not fun but I would double check all wires.

 

I would go over the grounds again, there's a bunch of em and the ones on the back of the motor are hard to see. I assume everything is drive by cable?

 

Make sure that the connections to the throttle body are good, and that there aren't any pins bent or anything like that. Triple check all of the grounds as mentioned above also.

 

i assume they can ground on the back of the heads, i recall hooking up two there. i will start with the gounds and see where that takes me.

 

Really strange. Is this fly-by-wire or cable?

 

Really sounds like a ground or you didn't hook something up. Did you say you double and triple checked everything?