Check Engine light ON.
OBD2 said replace O2 sensors.
Replaced with 2 Bosch. Reset OBD2.
Check Engine Light came back on.

Dealer says need to use Motorcraft O2 sensors or Computer will detect a fault.

Can anyone verify this?

 

Did it say replace the sensor or that they were out of spec meaning you are running too lean or rich....

And I say bull to the Dealer..

 

I thought Motorcraft O2's are Bosch?

 

Yeah, I'm betting most manufactures O2's are Bosch!

 

Dealer is full of it! On another note, very rarely do O2 sensors go out. Most likely something is occuring within the engine that makes the computer think that an O2 sensor is bad. Post the actual trouble code number here, and someone will come along with a possible solution. Also post year and engine, etc.

 

2001 4.2 6 cyl. 114k miles. I have read a few posts here and I'm wondering if:
The K&N filter has fouled the Mass Air Sensor.
It's true that O2 sensors are good for 70k miles.
There is a vacuum leak somewhere- though the truck runs fine

 

Left bank, right bank, running lean.

 

Cleaned MAS with brake cleaner.I have a K&N oiled filter. Lets' see if that resolves the problem

 

Maya's Dad
I have a 97 4X4 Lariat 3 door Flareside with a 4.6 that has the same problem. After installing a K&N filter, two codes poped up which were 0153 and 1151. I replaced the MAS and the O2 Sensor cleared the codes and they came back up. I am going to buy a regular air filter tomorrow to see if that clears the problem will let you know.

 

Yes there is a vacume leak. Kinda common with the 4.2 f150 &e150 and 3.8l in the windstars. The bolts that secure the upper plenum to the lower manifold develop a vacume leak and need to be replaced. I've done quite a few sets and if cures it every time. (Been working at the dealership for 10 years).

 

What is this vacume leak you speak of?

 

Eh...? Are you talking about the the plenum for the intake on top of the block. Can you be more specific. What bolts? Gasket replacement?

 

Rick1067- Thanks!

 

Checked for vacuum leak at plenum and various hoses, found none. Replaced Mass Air Flow- Light still on!

Will replace fuel filter- bet light remains on. Every time I see that light I see "Owner is a schmuck"

 

Went Back to the regular filter gave it a couple of days and the "Owner is a schmuck" Light came back on. The Manager at the local Auto Zone said he had the same problem with his Chevy and took it to the shop. The mechanic found where a couple of wires from the computer were the sheaths were cracked and condinsation built up on the wires.

I do not think this is the problem though.