Well if the tank is an 02 and its a returnless intake (04+) and you only had the feed line connected the pressure would be off the chart since there is no relief (return) from the pump. In that case no regulator would be very high pressure due to lack of flow.

 

I was meaning if he used the fuel system of the vehicle, and the engine of transplant (possibly newer) that did not have a regulator on the rail, the system would not be regulated. If the return line was not used, the pressure would be too high. It is a long shot but possible.

Oops I didn't see Atomic's response. That's what I meant.

 

Oh, right. No return line. Got it.

 

Ok regardless of fuel setup, its sucking air. If the TB is not opening and the engine is going to the rev limiter then its pulling air. If it was overfueling it then it would just stall out from being so rich. Too much fuel will not cause it to rev up if its not getting more air.

Check all of your breather connections on the intake, intake gaskets etc. To the original poster, if the engine is going right to the rev limiter once it is started then spraying carb cleaner or whatever you used is not going to tell you if there is a leak. You are already bouncing the limiter, so kinda hard to listen for a rpm increase.

As for the MAF, if you are starting the engine up cold and this is happening then the MAF is irrelevant. When you first start the motor cold it is in Open loop and not using the MAF till it warms up.

 

Want to rule out a vaccum cleak? Take your hand while its running and cover the TB opening... If the engine doesnt choke or die then its getting air from somewhere else.... Easiet way to check...

 

Ya I'm thinking it is getting air from somewhere. But the engine has no load on it, so I know it won't take to much air to do this. We did plug the IAC with our finger and still didn't help.

I'm prob going to mess with it some more this week. We may try a DBC throttle body, just to see if it may still be IAC related, even though we already plugged the hole with our finger.

As for the whole fuel thing, it has all the stock 6.0 components. 6.0 intake, rails, injectors, pump, regulator, all that good stuff. I did not check the pressure, I figured if it wasn't sputtering at WOT, then it's prob good lol.

 

unless the replacement pcms have your VIN coded in, they are not going to work, they need your VIN. I would replace the intake gaskets as suggested, then get a stock 5.3 tune and flash it. There are plenty of stock 5.3 tunes out there. Also, you will need to do a crank relearn. I'm sure the intake gaskets are shot and need to be changed anyways, so just do it!

 

Are any of the posts that hold the beauty cover on top of the intake broken off or snapped out of the intake. I've seen this before actually I'm assuming you would have noticed but possibly not if it's the stands toward the rear.