Starving for fuel?

[Travisfab]

My truck has 4.88 gears and will slam you back in your seat off the line, but through the mid to high range it's really lacking. It just seems like it needs more fuel. Anyone ran into this before i throw a new fuel pump in. It does have a new fuel filter, and other than this issue it runs great.

 

[2stroke]

Have you had a 4.0 OHV before? They make off the line torque and sign off around 4000 rpm. If you wait to red line to shift, you are actually slowing yourself.

 

[Travisfab]

Have you had a 4.0 OHV before? They make off the line torque and sign off around 4000 rpm. If you wait to red line to shift, you are actually slowing yourself.

More than I can count actually, lol! My buddy has a 94 Explorer also and his is totally different than mine

 

[2stroke]

I guess make sure you have good fuel pressure, good compression, and good spark (verify timing). Do all the basics like air filter, fuel filter, MAF clean, spark plugs, wires, coil good, etc.

 

[Josh P]

With each gear shift, you give up torque multiplication for speed. My van feels the same way, I can use the gas pedal to steer it in first gear but shifting to third feels like I set the parking brake.

 

[natenkiki2004]

Probably not a fuel issue unless it's misfiring or stalling. Always good to change the fuel filter though.

Going lower in gears, especially that low, it gives you tremendous torque but speed sucks. Your speed per RPM changes so you have to get up significantly higher in RPM to get more speed. Like 2stroke said, these engines are torquey down low and fall off well before redline. It might just be that you went too low in gears if you're looking to race. Low gears like that are great for offroading at slow speeds, takes a lot of stress off the transmission but you lose a lot of speed. You gotta have enough torque to get off the line but too much and you struggle to get speed. It'd be like trying to race in 4x4 low.

 

[Gadget X]

Just put some 33s on it to offset the low gear ratio! You would lose your "mashed into the seat" feeling on takeoff, but you would have a better highway feel.

 

[Travisfab]

I had this issue with stock gears and 32's. I can drive comfortably down the highway at 75. My issue is at wide open throttle at any speed. The motor sounds normal, but is not at it's full potential, then all the sudden it's like a shot of NOS kicks it and it returns to accelerating like it should.

 

[2stroke]

There is nothing we can tell you. Figure out if the problem is related to spark, fuel, or compression. Then we can help narrow it down.

 

[FR-425]

Have someone press the throttle pedal to the floor while you look to see if the throttle body is opening fully.

Throttle linkage thing.

Also verify that the TPS is sending high enough voltage to set the PCM to "Wide Open Throttle"

Simple test is to run the a/c (with the engine running) then smash it wide open and see if the a/c clutch disengages. If it doesn't then the WOT relay is not cutting out the a/c clutch which also means the PCM is not commanding WOT to the injectors.

WOT should occur at 80% physical throttle.