Ford Automobiles banner
1 - 12 of 12 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
Hello All,

This is my first visit to this forum and I hope I can contribute something as time goes on, and get some help when needed. I'm retired and enjoy doing things myself and learning things in the process.

My 2001 Taurus has a flashing 'check engine light' and my OBD2 scanner shows the PO302 code (indicating a cylinder 2 misfire). I've checked out the plugs and wires, listened to all the fuel injectors clicking ( thus assuming they are all getting electrical signals OK) and am now looking into the possibility of a clogged or stuck open fuel injector. I'm trying to narrow down the possible cause(s) of the problem before starting to take off the intake manifold and fuel rail to access the fuel injectors.

The scanner records the flash frame data related to the short term and long term fuel trim as:
STFT B1 = -4.6
LTFT B1 = +14.8
STFT B2 = -7.6
LTFT B2 = +4.6

My current understanding is that the LTFT B2 should be almost the same as the LTFT B1, and that the +4.6 value represents that the fuel is too lean. This would seem to me to indicate the fuel injector on the #2 cylinder is clogged or not opening.

I'd appreciate any comments or suggestions regarding my interpretation of the scanner results, or other diagnostic procedures I can try to determine the cause of the PO302 code.

Dale1
 

·
Registered
Joined
·
623 Posts
O2 sensors only read oxygen,with a misfire you have both unburned fuel and oxygen.The o2 sensor reads the oxygen and will try to richen the mixture.You have a regular 3.0 ?We have had some issues with injectors under the intake and its not hard to swap all 3 injectors (1,2 and 3) with 4,5 and 6.How did you check the plugs and wires ?
 

·
Registered
Joined
·
4,352 Posts
Just to add a little additional information to help clarify what phantom said above.
Bank 1 is always on the same side as Cyl #1.

BTW... Dale your's was an excellent initial post.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #4 ·
Phantom/Poppy
Thanks for your feedback. The engine type is the 3.0L EFI 6 cylinder ( the 8th digit on the VIN is a 'U'). I checked the plugs initially by taking them all out and checking the electrodes and gaps, and they all looked OK. I initially checked the wires by running the engine at night and looking for arcing between the wires. That's a pretty crude technique that has worked well in the past on occasion. But then I used an oscilloscope to look at the electrical impluses on all the plugs and wires. I used a capacitive pickup probe with the oscilloscape on each plug wire and all the electrical pulses appeared identical .... as best I could determine.

That led me to conclude (for the moment at least) that the plugs and wires were (probably) OK and focus attention on the fuel injectors.

I'm thinking of trying some fuel injection cleaner in the gas tank and run the car a bit to see if that will help, but I'm not a great fan of additives. My next option appears to be removing the upper intake manifold and fuel rail and changing the #2 cylinder injector.

Does this seem like a reasonable approach? What was the injector issues you mentioned Phantom ?
 

·
Registered
Joined
·
1 Posts
This is also my first visit and I have identical issue. Same code on a
2000 duratec dohc v6.
I have not solved it yet but read that 70 to 80% of the time mis-fire on these cars is a bad cop. I will have to swap to determine that but also a sticking injector is possible
 

·
Registered
Joined
·
3 Posts
This is also my first visit and I have identical issue. Same code on a
2000 duratec dohc v6.
I have not solved it yet but read that 70 to 80% of the time mis-fire on these cars is a bad cop. I will have to swap to determine that but also a sticking injector is possible
whats a cop????????????????????????????????????????????????????????
 

·
Registered
Joined
·
1 Posts
2003 Ford Taurus.
I have the #2 cylinder misfire and have already changed the
fuel injectors
Spark Plugs
Wires
Coil
synchronizer

I'm at a loss as to what the cause is. the car is running rough, has no pick up and definitely has a misfire.

HELP PLEASE......
 
1 - 12 of 12 Posts
Top