Going Insane...94 Explorer Loss of power

[Doc Hvac]

I started having problems with hesitation about 2 months ago and it seams that i have tried everything to solve the problem and it seams like i'm just changing parts and not getting anything fixed. here is a list of thing i've changed

Mass Air Flow Sensor.....Changed
Fuel Pump.....Changed
Fuel Filter.....Changed
Dpfe Sensor.......Changer
Checked Catalytic converter....OK
TPS Sensor.......Changed
ECM......Changed
Coil Pack.....Changed
Spark Plugs.......Changed
O2 Sensor....Changed
Injectors......Cleaned


The prob is that i'll drive for about 15 min from when its cold, it runs great,
then i lose power it won't go over 2k rpms and if i floor it it sounds like its bogging down if i turn the engine off, then back on it'll fun fine for about a min then it has the same problem until cools down until it's cold. need help any thoughts on what to check next.

 

[mawrazen]

Any codes????

 

[Doc Hvac]

before i changed the O2 sensor i was getting koeo 172 and 186 and koer i was getting 111. but now i have no CEL when i have the problem, and i tried driving it around while it
was running rough but still can't get the cel to come on.

172
(R,M)
Oxygen sensor not switching - system is or was lean - Single, Right or Rear HO2S - Fuel control

186
(M)
Injector pulse width longer than expected or Mass Air Flow (MAF) lower than expected - Fuel control

111

System checks OK

 

[nitro71]

How about the EGR? That can make it drive poorly. Could toss a junk yard one on and see.

 

[Doc Hvac]

i thought about changing the egr valve. but i don't know why the egr would cause hesitation. i'm having a lean prob....unless the egr valve has something to do with the a/f ratio.

 

[Doc Hvac]

also i just ran the codes again koeo #111, koer #111, fuel injector test #9,

 

[Doc Hvac]

update, i went run the truck a couple times and finally got the CEL to come on and koeo, 186

 

[Tbars4]

...Have you cleaned the MAF itself???
http://www.explorerforum.com/forums/showthread.php?t=256453&highlight=186

 

[janolsson]

Coolant temp sensor??

 

[Doc Hvac]

I have removed the MAF sensor from the housing and sprayed it with cleaner, i have not checked the temp sensor or the air temp sensor i'm going to check those out. question....can you relocate the air temp sensor, becuse the intake manifold is vary hot where the sensor is??

 

[Doc Hvac]

i think i fixed it. i was checking out the Intake air temp sensor and found i had no resistance through the sensor, removed the sensor found it was covered in oil. put
sensor back in reconnected sensor. checked resistance and found that it was correct.
changed sensor, went run truck and every time i wot it would go into passing gear have a lot of power now, hope that fixed it. will write back to update progress....thanks everyone