bought a 2005 exp EB 4.6 4x4

[lidavef]

I need a little input from the people that know. I replaced my 99 exp 4x4 4.0 with a 2005 4.6 4x4. Do the v-8s tend to 'roar' as they accelerate? It also lunges from a stop when you press on the gas pedal. Would that be a problem with the pedal position sensor or is this tranny related? it runs like an ape on steroids and seems to shift fine.

 

[mountaineer2004]

Yes, it does roar upon acceleration.
The gas pedal thing is called "tip-in", or at least that's what I call it.
And yes, it is def excessive on these cars.
Way too much response in first 1/4 of pedal travel.
I smoothed mine with a tune from Henson, but he's no longer in the biz, I believe.

 

[2Trux]

The start lunge on mine decreased when I cleaned the throttle body. I think it was sticking and then would pop open as I gave it more pedal. Might be worth a try, it's cheap and probably needs to be done anyway.

 

[lidavef]

The start lunge on mine decreased when I cleaned the throttle body. I think it was sticking and then would pop open as I gave it more pedal. Might be worth a try, it's cheap and probably needs to be done anyway.

Bought a can of throttle body cleaner, took it apart, cleaned a lot of yuk out of there, reassembled, test drive. 100% better. Thanks!

 

[apenland01]

The biggest source of that roar is likely the fan clutch. These fan clutches tend to not relax until it's been at higher rpm's for a bit, especially aftermarkets.

 

[lidavef]

The biggest source of that roar is likely the fan clutch. These fan clutches tend to not relax until it's been at higher rpm's for a bit, especially aftermarkets.

that's what i thought it sounded like. do aftermarket fans reduce the noise?

 

[apenland01]

that's what i thought it sounded like. do aftermarket fans reduce the noise?

For my Explorer it either made it worse, or the old one had been going out for so long I didn't realize it wasn't making as much noise and I got used to less noise. So when I replaced it, I really noticed it again. I replaced mine with a Hayden I believe and it definitely works well, but it lets you know it's there for sure. As long as the engine and A/C stay cool when I'm idling in traffic or at a stoplight, I'm happy and don't care if it roars on takeoff...

 

[SyberTiger]

I agree, the roar is the fan clutch. From my experience, I changed out my fan clutch with an aftermarket product just because I was changing out the water pump and thought I might as well change it out. The aftermarket product roared so loudly even when it was clear the engine was warm but not even close warm+ that I went back and put my factory original in.

 

[rrgone]

I get to drive a 2002 Explorer V8 (mine) and a 2005 Mounty V8 (mom in law) all the time. The '05 is difficult for me to take off smoothly from stop, even when fully warmed up. I've always chalked it up to mechanical vr. electrical throttle control. Maybe I will have a go at cleaning the TB on the Mounty.