O2 Sensor; MAF Sensor
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O2 Sensor; MAF Sensor
Greetings People,
This is my first time here. I got a 98 Mountaineer, 5.0 engine, AWD. She's treated me well....144K miles with no major issues and she's just about paid off ( SMILES ). I just had a tune up ( belt and distributor cables..etc.) I had the "check engine" light on for about a year and a half. AT that time the dealer explained that the MAF was probably dirty as they are very sensative but she runs perfectly otherwise. So I decided to just let her be. Last week...got a tune up...and the mechanics was able to turn off the "check engine light". However, after getting home ans starting her up the next morning...the lite was back on even though the enigne was running smoothly. I waan do a few self repairs to save myself money. I figured maybe I could replace the MAF and the O2 sensor myself after reading the Chillen manual. But one question..where's the damm O2 sensor located..Chillen does not show the location...hehehhehh. YOu will be seeing alot of me here. Having been on alot of forums for other subjects..I have learned alot. SO.....BRING IT ON!!!!!!
This is my first time here. I got a 98 Mountaineer, 5.0 engine, AWD. She's treated me well....144K miles with no major issues and she's just about paid off ( SMILES ). I just had a tune up ( belt and distributor cables..etc.) I had the "check engine" light on for about a year and a half. AT that time the dealer explained that the MAF was probably dirty as they are very sensative but she runs perfectly otherwise. So I decided to just let her be. Last week...got a tune up...and the mechanics was able to turn off the "check engine light". However, after getting home ans starting her up the next morning...the lite was back on even though the enigne was running smoothly. I waan do a few self repairs to save myself money. I figured maybe I could replace the MAF and the O2 sensor myself after reading the Chillen manual. But one question..where's the damm O2 sensor located..Chillen does not show the location...hehehhehh. YOu will be seeing alot of me here. Having been on alot of forums for other subjects..I have learned alot. SO.....BRING IT ON!!!!!!
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From: Fort Smith
Welcome to FTE Mountaineer40! 
You should have 4 O2 sensors on your Mountaineer. They are loacated on the exhaust pipes. There will be two in front of the pre cats, and two after the back cats between them and the muffler. They screw into the pipe, and have wires coming out of the top and up.
I would go by Auto Zone and have them check the codes for you - they do it for free. Let us know what codes you are getting, and we can tell you which O2 sensor is bad.
You should have 4 O2 sensors on your Mountaineer. They are loacated on the exhaust pipes. There will be two in front of the pre cats, and two after the back cats between them and the muffler. They screw into the pipe, and have wires coming out of the top and up.
I would go by Auto Zone and have them check the codes for you - they do it for free. Let us know what codes you are getting, and we can tell you which O2 sensor is bad.
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CobraXP....
I did what you suggested...Went down to AutoZone and got the codes. ADn to make sure they were not pulling my leg or something..I went to a second store just to confirm that the first codes were correct.
Here they are:
P0401 EGR something....
P0153 ..sensor check slow response
The OBD II gave these codes twice...two of the same codes twice. The second time was from something like a backup or history memory. Got any idea what they mean?..Thanks again for the suggestion....
Mountaineer40
I did what you suggested...Went down to AutoZone and got the codes. ADn to make sure they were not pulling my leg or something..I went to a second store just to confirm that the first codes were correct.
Here they are:
P0401 EGR something....
P0153 ..sensor check slow response
The OBD II gave these codes twice...two of the same codes twice. The second time was from something like a backup or history memory. Got any idea what they mean?..Thanks again for the suggestion....
Mountaineer40
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Cobra...
Did some more homework.This is what I found.
CODE NO. MAKE CODE DEFINITION
P0153 Generic O2 Circuit Slow Response (Bank 2, Sensor 1)
CODE NO. MAKE CODE DEFINITION
P0401 Generic Exhaust Gas Recirculation Flow Insufficient Detected
Now....what do they mean?.....hahhahah!!!
Did some more homework.This is what I found.
CODE NO. MAKE CODE DEFINITION
P0153 Generic O2 Circuit Slow Response (Bank 2, Sensor 1)
CODE NO. MAKE CODE DEFINITION
P0401 Generic Exhaust Gas Recirculation Flow Insufficient Detected
Now....what do they mean?.....hahhahah!!!
Last edited by Mountaineer40; Nov 21, 2003 at 04:31 PM.
Logistics Pro
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From: Fort Smith
I'm at work right now and can't remember which sensor is which (as far as which bank, etc). I'll have to get that for you when I get home.
The EGR code means either your EGR valve is bad, or the DPFE sensor is bad. They are located on the back of the upper intake. Attached is a pic of the rear of your intake. You will see the DPFE sensor, and the EGR bolts up to the intake elbow (where the piece is missing in the pic). It is round...
The EGR code means either your EGR valve is bad, or the DPFE sensor is bad. They are located on the back of the upper intake. Attached is a pic of the rear of your intake. You will see the DPFE sensor, and the EGR bolts up to the intake elbow (where the piece is missing in the pic). It is round...
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Thanks Cobra for your response. I feeling like I've learned a ton in under 5 hours!!!! LOL
Mountaineer40
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Logistics Pro
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From: Fort Smith
No problem! I've been there, so I know the feeling. I didn't know about this site or some of the others at the time, and had to figure most of this stuff out on my own.
If you do a search, you will find a few posts that talk about which sensor is which. The EGR and O2 sensors are a common item to go out on Explorers, along with the IAC. Don't get too concerned about any real problems - its normal wear and tear...
But you will probably have a few choice words when it comes time to change the EGR setup...
Everyone else has.....
If you do a search, you will find a few posts that talk about which sensor is which. The EGR and O2 sensors are a common item to go out on Explorers, along with the IAC. Don't get too concerned about any real problems - its normal wear and tear...
But you will probably have a few choice words when it comes time to change the EGR setup...
Everyone else has.....
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I feel ya on that. For now though...I'm gonna stick with standard parts until I learn more. I came right home and got in here and have been reading and learning for the past 2 hours straight!!!
Thanks again!!
Mountaineer40
PS I'm trying to post a pic of my truck also...bear with me!!
Thanks again!!
Mountaineer40
PS I'm trying to post a pic of my truck also...bear with me!!
Logistics Pro
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From: Fort Smith
By the way - before you change any of the parts, unplug your PCM for about 5 minutes, then reconnect. It is a 10 or 12mm bolt in the wiring harness on the PCM. This does the same as diconnecting the battery to reset the PCM, except you don't lose you radio presets, etc, that come with disconnecting the battery.
Reason I say this is because you mentioned something about one of the codes being in memory. It could have been a fault code that kicks, and might not actually be bad. After you do this, drive around and see if the light comes back on. If it does, have the codes checked again to see what you get then...
Might save you a dollar or two...
Reason I say this is because you mentioned something about one of the codes being in memory. It could have been a fault code that kicks, and might not actually be bad. After you do this, drive around and see if the light comes back on. If it does, have the codes checked again to see what you get then...
Might save you a dollar or two...
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PCM...Performance Computer Module? ( a logical guess )
And you know the next question....where is that?? LOL
M40
PS Still reading and learning as we speak!...LOL
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Update: Opened that Chilton book....answered my own questions.
Thanks again!! LOL
PCM=Powertrain Control Module. (whew!!! )
And you know the next question....where is that?? LOL
M40
PS Still reading and learning as we speak!...LOL
---------------------------------------------------------------------
Update: Opened that Chilton book....answered my own questions.
Thanks again!! LOL
PCM=Powertrain Control Module. (whew!!! )
Last edited by Mountaineer40; Nov 21, 2003 at 05:08 PM.
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Last edited by Mountaineer40; Nov 21, 2003 at 06:43 PM.
Logistics Pro
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From: Fort Smith
You can create a user's gallery and put all your pics of your ride in it...
Your PCM is the same as your computer - it is located on the firewall under the hood on the passenger's side. Look for a black plug with one bolt holding a big group of wire....
Your PCM is the same as your computer - it is located on the firewall under the hood on the passenger's side. Look for a black plug with one bolt holding a big group of wire....