Rough acceleration and won't go over 50mph

[Towerking250]

Hello everyone!

My girlfriend's 2000 Ford Explorer is driving me insane. She has a 2000 Ford Explorer xlt 4.0 OHV 2wd auto. She has had nothing but problems with this vehicle and I have hit a wall and an empty wallet. The current situation is as follows, tough to start occasionally, runs rough at any speed, will not get past 50 mph no matter how much or little I pre the gas, stalls sometimes at a stoplight. This does not occur when in pArk and idles around 750-1000 rpm.

What is new:
Alternator, IAC, crank position sensor, fuel pump, in line fuel filter, plugs, ignition wires, coil pack, all gaskets from head gaskets up, battery, radiator cap, little black module that has 2 hoses from exhaust (can't remember what it's called).

Maintenance performed:

Oil and filter changed, cleaned throttle body, cleaned MAF, cleaned intake, new air filter, cleaned PCV

No current DTC's, no CEL, fuel pressure is 60's, spark tested.

I have been searching the threads for hours and cant seem to find on that fits my issues. PLEASE HELP and thanks in advance.

 

[pcam13]

Hmm.. What does your throttle % say. possibly something to do with it not seeing you are pressing the throttle wide open...

 

[Towerking250]

That's what I thought at first but when it is in park I can rev to 6k or higher. And the problem is in all gears. Even when I shift to 1st and 2nd

 

[Runnin'OnEmpty]

I suspect it's either TPS or MAF sensor related, although
both should trigger a fault code.
Do you have any pending codes?

The TPS is easy to test with a multimeter; the procedure
is on this forum somewhere. Try unplugging/replugging
it first; might be something as simple as a corroded terminal.

You might try unplugging the MAF sensor and see what
effect that has on how it runs. (After 2 starts this will
illuminate the MIL.)

 

[1998Exp]

How about the base engine? Did you test compression/cylinder leakage?

...
What is new:
Alternator, IAC, crank position sensor, fuel pump, in line fuel filter, plugs, ignition wires, coil pack, all gaskets from head gaskets up, battery, radiator cap, little black module that has 2 hoses from exhaust (can't remember what it's called).

Maintenance performed:
Oil and filter changed, cleaned throttle body, cleaned MAF, cleaned intake, new air filter, cleaned PCV
No current DTC's, no CEL, fuel pressure is 60's, spark tested.

 

[Towerking250]

Sorry I haven't responded. I just got home. I have not done a compression test yet and will update my TPS and MAF findings in a bit as well as any pending codes that may be.

 

[Towerking250]

Just an update: I ran a KOEO AND KOER TEST AND THE CODES WERE P1000 and P 1116

 

[Turdle]

There are 2 coolant sensors used on explorers.One drives the temp gauge,and is actually sender, while the other sends temperature readings to the ECM. It is this 2nd sensor associated with the code displayed.

For the P1116 code the first thing I would check is the coolant level in the radiator itself. Do not rely on the overflow reservoir.

Then I would check the wiring associated with the ECT sensor, before replacing the sensor.

 

[Towerking250]

There are 2 coolant sensors used on explorers.One drives the temp gauge,and is actually sender, while the other sends temperature readings to the ECM. It is this 2nd sensor associated with the code displayed.

For the P1116 code the first thing I would check is the coolant level in the radiator itself. Do not rely on the overflow reservoir.

Then I would check the wiring associated with the ECT sensor, before replacing the sensor.

Which one is which? I have the flush fluid and will be flushing the entire system today as well. Also I found that my cylinder 4 ignition wire got slightly pinched under the upper intake and burned through. I feel that is my culprit and will be changing the wire in a bit. I will updat my findings soon. Thanks!

 

[Turdle]

The gauge sender has 1 wire and is to the left of the coolant inlet tube ( when viewed from the front)

The ECT sensor has 2 wires and is more or less right under the throttle body, more to the right side of the intake manifold.

Let me know if you find them.

 

[Towerking250]

Ok so I replaced the bad ignition wire and it is running better but now gives me a cylinder 3 misfire. And yes Turdle I found them thanks. I now have an issue that resembles a slipping clutch. It will get to speed but slowly and now I wouldn't dare pull out in traffic unless I have a LONG distance. Could that be from the TCC on the trans?

 

[Towerking250]

UPDATE!!!! So after doing a resistance test on the injector for cylinder 3, it passed with 18+ohms. I checked spark which was present, but when I tested resistance on the plug wire it was erratic so I replaced it and test drove. Ran better but still got the misfire code. I pulled the plug and it didn't look bad but I replaced it and cleared the code. After multiple test drives the code is still gone and running much better. I still believe she has a worn torque converter but as for the previous issues, they are repaired. Thanks for all your help and I hope this helps future explorers' problems!