Ok so I've tried almost everything there has to be something I missed. I have an 06 ford expedition. So I'm driving from Alabama to Texas when I get to about 60 mph and the engine revs/rpm up and the truck wasn't moving. This happened continuously for about an hour. During that time I'm also losing pressure. When I press the gas it's like it won't take it, also jerking very bad at 60 mph. Finally I just get worse until I'm no faster than 40 mph. I pull over on the exit straight to autozone, I'm thinking fuel filter. Hop out change it because sure enough it was clogged very badly. Still doing the same thing. I've changed 4 spark plugs, 1 ignition coil, the maf sensor, cleaned all fuel injectors, checked all vaccuum lines even replace two, did a fuel pressure test with pressure gauge, it passed, full bottle of tune-up (Lucas), octane booster, 2 cycle oil, you name it I've tried it. With no changed in result. This has been going on two days now and I've spent a fortune on parts. Only codes that are coming out are p0171(bank 1 too lean) and p0175 (bank 2 too rich). Somebody help please. I'm stranded and have already missed two days of work!!!

 

If the engine revs up but the truck doesn't move, that would suggest a transmission or, if a manual, a clutch problem.

 

So ur basically saying I've spent money on all these parts and the problem is a bad transmission. I'm definitely not going anywhere. Hitch hiking!

 

so the transmission would make it powerless,jerk, and not take gas? Idle rough? All the things I explained sound like transmission?

 

Sounds that way. With the engine reving like that, there has to be a loss of physical connection between the engine and drivetrain.

 

o man that's not good, looks like I'll be stuck here for days!!! Just my luck

 

Just for laughs, did you by chance check the tranny fluid (engine running and in Park) to make sure it wasn't low? A low fluid condition will also cause the symptoms you're experiencing.

 

Yes I did, I've read forums where it says if the tranny is bad the transmission fluid would be darker n not so transparent. Not only have I checked the level I checked to color n it's as if the fluid is new straight out the bottle no change in color.

 

And if it is transmission why do I have no other tell tell signs of a bad transmission? There is no odor or discoloration in fluid. It shifts in and out of gear just fine, it's not noisy, nothing. Only thing that leads to transmission is when at high speed it seems as if it's slipping into neutral or something then back normal.

 

And if it is transmission why do I have no other tell tell signs of a bad transmission? There is no odor or discoloration in fluid. It shifts in and out of gear just fine, it's not noisy, nothing. Only thing that leads to transmission is when at high speed it seems as if it's slipping into neutral or something then back normal.

 

THAT is a transmission problem.


As alloro said:
"Dirty" transmission fluid is due to the particles of friction material suspended in the fluid. However, worn-out frictions are n ot the only possible cause of transmission failure. Other causes in the hydraulic circuits (leaking seals, cracked pistons, etc) can cause many of the same symptoms without burning up the clutches.

 

If it were a trans issue, then why would it throw codes that would allude to a vacuum issue of O2 sensor issues?

I understand that a hand held code scanner may detect all issues but........

 

My point exactly! Like out of all it's doing I only see one thing leading to transmission. There are tons of things to look for when a transmission is bad/gone, I don't see any. If it went out it went out quietly.

 

Concentrate on your codes and stop worrying about it being the transmission, it's telling you what's wrong. Bank 1 is lean Bank 2 is rich trying to compensate. So why is bank 1 lean? That is usually an unmetered air issue or an O2 issue/sensor issue. Transmissions don't set bank lean codes.

 

Ok with that being said I did try to concentrate on why I was getting those codes. I did a fuel pressure test that passed, running and not running. I did the dangerous what people tell u not to do and sprayed carb cleaner in the back of the intake manifold and throttle body to listen for change in idle. Changed maf sensor. And I was told by a mechanic not to worry bout changing o2 sensors bc that wouldn't make it run as rough as it's running. I don't know what to do next, extremely frustrated.