93 cuts off when gas on the floor

[fordforlife]

My 1993 3.0L auto 4x4 ranger cuts out and backfires when you put the gas pedel on the floor. If you don't let up truck will cut off. I have checked fuel pressure, changed fuel filter, spark plugs, wires, and air filter. I have cleaned the MAP sensor and took off the cats. Still having the same problem. Truck runs fine until full throttle. I'm thinking maybe the throttle position sensor.

[bemo415]

could be something with the fuel injectors too

[Mike J.]

You're right, could be the TPS. Pull the harness off the tps and check it's resistance while someone pushes the pedel down to full throttle. Doing it this way ensures the position is the same as when you're driving it. The TPS should show resistance all the way across the range. If it shows infinity (open) at the point of your problem, then it's bad. The engine doesn't drop to idle because the computer thinks the TPS is completely gone.

One other thing, there's a Wide Open Throttle sensor that tells the computer when you're in WOT. You may also want to check the codes or have a diagnostic accomplished to ensure the WOT function is working properly.

mj

[fordforlife]

I checked the tps good. Anyother ideas? I have changed the spark plugs, wires, cap and rotor also. If the intake system is not all together could that be it? The intake is fine from the air box to the throttle body but before the air box is just duct tape together. Do you need that bimetal heating thing that is in the intake?

[pick-up-man]

i see the problem as one with the throttle body istelf, the longer u let it go, the earlier in excelleration you will encounter your problem. i had a similar problem with another truck, i replaced injectors, wires, plugs, oxygen sensors,and air hoses and nothing. then i replaced the entire throttle body (with a used one) and perfecto, the truck ran like it did when it was new.