Dave009

After close to a year of doing everything I could think of and everything the dealer suggested, and everything that just plain made sense in the service manual... My '02 F150 4.6l still has an intermittent power loss and it's dangerous.

the list of new parts would spin you head 10-20 miles runs like a champ then wham any speed any condition loss of power 70 mph to a coast climb a hill drops dead till it kicks in again then spins the wheels if I'm not careful and goes a couple more miles.

No Codes at all ever.

starts strong runs like brand new (technically it is from the fuel pump to the throttle body and every where in between )

New motorcraft plugs gapped to .054
New MC wires
New MC Coil

Stumped

Any help or ideas will be applauded and shared this can not be the only no code nightmare :-)

Talk to you soon!

MisterFord

What do you mean loss of power? What happens when you press the gas when this happens? Is it like the engine is dying, is the engine lugging, does the engine rev up like it's in neutral?

Frank_Ford

Have you checked your EGR valve? You can take it off and clean it so it operates smoothly. Knock off the carbon with a screw driver and do not get solvent on the diaphragm. If you get solvent on the diaphragm, you will have to replace the valve. Also, make sure the pipe from the EGR to the manifold is not obstructed. Run a wire through it when you take off the EGR and if obstructed, replace it for about $50 part cost.

gearhead88tc

i 2nd the EGR

4x4dave

Your truck is probably running lean, does it run out of power and then lurch forward?

Dave009

Hey Mister Ford thanks for taking a look, to me Loss of power, what I mean there is nothing under the pedal engine has no response and I am coasting.. I tap and massage the pedal till it feels like getting going again.

Guys the EGR Valve and every thing else is brand new replacement some Napa parts most Motorcraft

Keep up the great suggestions guys we'll nail this gremlin yet!

Have great days and watch the weather where ever you all are!

MisterFord

I'm definitely no expert here (especially on computerized vehicles), but here's my 2 cents. This seems to me like some problem with the connection between the gas pedal and the engine. If the engine is still running (basically idling) and massaging the pedal brings the power back, then there must be something that is actuated when the pedal is depressed that is not working correctly or is shorting out.

Zrock

Have you tried a known good computer? Had a veh a while ago that would randomly stall when you turned left. It spend a good 2 months in the shop as it would show no codes. finally as a last resort they swapped out the computer with a scrap yard unit and never had the issue again.

gator0308

What about the throttle position sensor on the side of the throttle body? It may be going bad and not telling the computer that your even giving the vehicle gas.

Dave009

Thanks for contributing, so no lurch... just does not fire or back fire then while babying the pedal it kicks in a keeps going some times for 20 miles sometimes for 20 feet!

Here's a list of the so fars....

New:

Spark plugs gap .054 MotorCraft
Coil Pack MC
Wires MC
EGR
PGV (PCV?)
Fuel Pressure Regulator
Fuel Pressure Relay
Fuel Pump (I am now a wiz at dropping the tank as I did it 2 times)
The Throttle is connected via a cable not the computer.
Fuel Filter 2 x's
All the fuses are good.

Keep thinking!