Hey guys, I have a 4.6 L 01 Ford F-150 2wd super crew cab truck with 183k miles on it. I recently replaced the engine with a new 4.6 long block with the heads ported out. I replaced the engine due to excessive oil consumption and loss of power, esp going up a hill. I love the truck so I decided to replace the motor instead of getting rid of it thinking that would solve the problems that I was having. I pretty much replaced everything under the hood.
Delphi coil packs
motorcraft plugs
BBK alum. throttle body
Dorman intake manifold
water pump
power steering pump
MAF sensor
TPS
fuel tank
fuel pump
fuel filter
cold air intake
and I had a SCT programmer custom tune
Since replacing the engine, I've had pretty much the same problem with the loss of power going up hill ( from a slow speed, I can hold the gas pedal all the way to the floor and the truck won't go any faster) Also, going from a complete stop the truck will stall for a sec, then go, and the RPMs will jump up to 3000 rpms. I also have a occasional "shudder" that I had prior to installing the new engine. So I'm thinking that my torque converter may be going out. So the other day I did a stall test( truck in drive, foot on brake and pressing the gas pedal to the floor) and it only got up to 1000 rpms. So needless to say I'm at stand still to what could be causing the loss of power other than the torque converter. Any suggestions will be greatly appreciated!!

 

Did you put this engine in yourself or did you have some local shop do it for you? Reason I ask is that there might be something in the ECU or PCM that has to be calibrated with IDS.

It could be something as silly as a bad throttle Position Sensor. If you didnt do the work yourself, I would take it back to where you had it done and tell them something just isnt right.

If you did it yourself, I would say check that Throttle position sensor cause the way you describe your issue has hallmarks like a bad throttle position sensor would.

I'd consider taking it to your local Ford dealer might cost you a couple hundred bucks but take it to a Ford Dealer and have them put it through some tests with their IDS and they should be able to figure it out for you.

Last thing you want to do is throw parts at it

 

Thank you for the reply. After I read your reply, it dawned on me that I replaced the TPS on my old engine but I was in a hurry when I replaced it and did not pay attention to how it when on so I just put it on there and hoped for the best. So that may be something that I try first. If that does not work then I will take it back to the shop that installed the engine and let them figure it out.

 

Is the exhaust original? If so it could be partially clogged and building backpressure during high engine demands.

 

lntially the the cats were stopped up so I had them cut off and straight pipe welded where the cats were and still no change

 

Check your throttle body cable, it might be stretched and not allowing the throttle body flap to open all the way. You can have some one help you, simply remove the intake tube off and have someone press the pedal to WOT engine off and see if it opens all the way if it's not, you can add a few zip ties to the throttle cable slack where the pedal is at and hopefully that cures your problem.