Need Help: 2002 XLS wont go above 10mph/2000rpm

[DocRizk]

Ill try and make this short and sweet:

bought a used 2002 XLS and the only issue I had was ABS light coming on (feels like pedal pushes back and then light kicks on), rear wheel bearing and 4x4 wasnt working. (4x4 lo would work when ignition on but nothing after that point)

So I had replaced a rear wheel bearing, rear brakes and had a dealership run my VIN for the proper 4x4 module replacement.

The original 4x4 module ended in AF and the new one in AL. So i plugged it in and BOOM... i had a truck once and for all.

2 days later we got hit with a bad storm and i looked forward to the chance to test the truck in the snow. I was driving home, up a hill and I noticed the truck wasnt really producing much power so i pushed the throttle a little harder and it reved up for a moment and then lost its engine power again and krept up the hill at 10 mph. It was idling extremely rough to the point of stalling when givin any throttle.

In the following days I deduced that the plastic plenum had 2 thumb tac sized holes melted through the top right after the throttle body. I still have no clue how or why this happened but I plugged the holes, replaced the upper intake gaskets, EGR gasket, cleaned the throttle body and MAF and also replaced the air intake filter and fuel filter. Also when the I pulled the TB i noticed the inside of the plenum was melted, right below the holes i found. Im assuming someone sprayed ether or other non plastic friendly chemical in their. No other vacuum leaks were found.

The current state of the vehicle is, well parked, but it will start right up,idle fine but still will not go above the 10mph/2000rpm mark.

The only code that was pulled was for the idle air controller, but im not sure if this would cause the issue im having and also if it was just aresult of removing these parts as a part of the process.

If anyone has any ideas as to what im dealing with please let me know and i will provide more info if i can.

Thank you

 

[Number4]

I had a bad fan clutch one time (on an S10) and the engine would rev and sound like it was hauling arse, yet the vehicle wouldn't move much. Took it to Double A, MCO and they identified it as the fan clutch, which it was.

Probably too easy though.

 

[colintrax]

Check fuel pressure, if it's good look at the cats after driving for a few minutes. Glowing red would indicate they are clogged. If you can, take it to a muffler shop. For $20 they can weld in a nipple and check the exhaust pressure.

 

[ExploreDeep]

Just had this happen to me. Throttle position sensor.

 

[extsp2]

Throttle position sensor is common. Find someone with a scan tool that will read the TPS and see what it's doing.

 

[DocRizk]

I have a code scanner but the tps never showed itself. Does this require a special scanner? I'd think the cat but it was pretty sudden.

 

[ExploreDeep]

If it's not showing itself, i'm pretty certain it means the sensors dead. Never hurts to replace it whether bad or not. Gave mine more of a pick me up after i changed mine out. Only 65 bucks at the local auto shop and takes about 30 mins to replace..

 

[DocRizk]

so i replaced the TPS today and it actually made it worse somehow. code for the TPS now showed up after installing a new one.

still no power and the truck stalled out in the street, wouldn't start right back up. only started after prolonged cranking. any ideas?

 

[colintrax]

so i replaced the TPS today and it actually made it worse somehow. still no power and the truck stalled out in the street, wouldn't start right back up. only started after prolonged cranking. any ideas?

Did you do what I suggested?

 

[DocRizk]

Haven't checked fuel pressure but there's fuel at the rail. Can't get it to a shop. Won't make it down the street

 

[ExploreDeep]

Wow... That's a tough one man I'm sorry my suggestion made it worse.

 

[DocRizk]

UPDATE: so I finally got sick of trying to figure it out and had the truck towed to my friends shop. They cleared the code again and ran it and it ran fine. Im starting to think the cat was restricted because it still feels like it is slightly restricted and now i can hear rattling sounds coming from that area when pressing the throttle. I think ill just striaght pipe it and see what happens. on to the next issue.... ball joints!!! thought the shaking on braking was the rotors so i changed them and the old ones were in great shape. so more money thrown away. im thinking the balljoints are causing that issue. still not sure about the ABS issue. cleaned the sensors and it didnt help.

 

[Number4]

The other day, I had a pending P2106 code. Doing research, I came across this video.

http://www.youtube.com/watch?v=_io9rYErdNE

It's a little long and you may not need to watch it all, but I'd highly encourage it.
Basically, a bad ABS sensor can cause Limp Mode. (You'd think you'd get a code, but these are Fords. Fords like to not show codes until the car is on fire and everyone is already staring at it.)
Keep in mind, you can't always tell the functionality of a component by how it looks. Internal wiring etc. can all be bad.

On a side note. Whenever you replace an electrical component (engine control wise at least) you must (or should) clear the adaptive learning in the ECM. Otherwise, your new component will be treated by the car as if it is the old one.

http://www.explorerforum.com/forums/showthread.php?t=396533

This link is a must. Don't just clear the settings, but pay particular attention to how to restart and run the vehicle after. (I apologize in advance, if this part has already been done.)