Low Power, No Acceleration, Top Speed 55mph, Top RPM 3000, Low Idle 600rpm

[BAM2011]

2002 Ford Explorer - 225K miles - 4.0L - Auto4WD

Symptoms:

• Low Power
• Top Speed 55mph
• Top RPM 3000
• Funny shifting points
• no Acceleration
• Low Idle 600rpm.

Recent Work: Recently had the codes P1131 P1151 P0171 P0174 that lead me to a large vacuum leak that I fixed, reset the computer by disconnecting the battery, engine is running smooth now, no new codes, but still no power.
In the past few months, I've replaced the fuel filter, plugs, oil, and air filter, thermostat and thermostat housing.

Ideas:

• Could my Cats or pre-Cats be clogged?
• Could my fuel pump be not keeping up with demand?

 

[matt0248]

yes and yes to the fuel pump or plugged cats. Also try cleaning the throttle body and MAF sensor.Although, with the symptoms of lack of power and not being able to get the rngine to rev past 3k it sure points to plugged cats, at least in my mind. Even with a weak fuel pump you could open the throttle slowly enough to get past 3k rpms.

 

[Javadog123]

Sounds like cats to me too.

 

[jayton]

Take the o2 sensors out to see if it clogged cats. If it is loud and you can finally accelerate again, then it was the cat. Exhaust will escape out of the o2 sensor holes allowing you to either confirm or rule out cats.

 

[Yerba1]

Is there a chance that the cats would free up once the engine heats up? I've replaced all of the top of engine sensors in my 1993 - MAF, HEAT, IAC, ABC, DEF, FCK IT, etc.... and it still won't accelerate - until the temp gauge shows some heat - and then it's like a turbo kicks in and it's good until it cools down. This only became a problem once the temps fell below 40 degrees this fall. The Cat housing was rattling at about the same time the problem developed.

 

[jayton]

Nevermind, I posted the wrong thing.

 

[Turdle]

Is there a chance that the cats would free up once the engine heats up? I've replaced all of the top of engine sensors in my 1993 - MAF, HEAT, IAC, ABC, DEF, FCK IT, etc.... and it still won't accelerate - until the temp gauge shows some heat - and then it's like a turbo kicks in and it's good until it cools down. This only became a problem once the temps fell below 40 degrees this fall. The Cat housing was rattling at about the same time the problem developed.

ECT sensor? There are 2 coolant sensors, one is for the gauge only, the other sends output for fuel delivery curves.

 

[fedyfedz]

sounds like its in failsafe mode

 

[Traillover]

OK, I'm really new to this blog (09), but any time I've had those exact symptoms, the problem always turned out to be O2 sensors (either 1 to 4) had to be replaced.... I might add, while driving under those conditions, the fuel efficiency dropped to 5mpg....

 

[ExplorerArek]

this is my exact problem too

Did anyone figure out what this guys issue was?

2000 Explorer

Symptoms:
Low power
Crap gas mileage
Shifts at 2000 to 3000 rpm for each gear. ( 3000 if I shove pedal to floor)
Acceleration is Smooth
Idle has a slight hiccup
No check engine light

I have scene posts with this problem and lot of suggestions but no one has posted a success...

 

[Yerba1]

bad ECM

Look in the junkyard for a comparable mile replacement. Mine cost $40 after days at the mechanic and countless sensor replacements and cleanings....

 

[ExplorerArek]

why a comparable mile replacement ?

Does mileage make a difference? I figure as long as it's the same year or near year?

Also any way to test this thing ?

 

[Yerba1]

I've always tried to keep miles close - old wives tale maybe ? - I don't know about testing - I just told my yard that if it didn't work - I'd bring it back for a refund - and they were cool. I think my daughter fried hers due to other issues - bad battery ground cable - transmission issues - hot wiring - in the end - too many cooks in the kitchen and something critical burned up. It was a 15 min. swap of the ECM and it ROARED back to life. I didn't get into actual part numbers - wouldn't you think that there are 1000s of these units around? Good luck.

 

[ExplorerArek]

okay figured out what it was, it's so stupid. If the top symptoms happen then try this. Go to the engine bay, First check for slack on the throttle cable, if so fix it. How I did it i got a small binder clip went to the gas pedal found where the cable comes in and just clip on the binder clip as a spacer. Second see how far the throttle will go, it should go to the 90 degree mark. If it doesn't take off the four bolts and clean throttle body and make sure its able to move. On mine the plastic piece with what looks like a comb on the bottom was hitting the butterfly valve, I just got a obd II scanner today with live data. My TPS sensor read 30% at WOT which made lead me to this. hope this helps someone. ####ing thing drove me nuts. Less learned no engine light or codes check for mechanical issues. SIMPLE mechanical issues like a throttle not being able to move! god I feel stupid