2010 fuel injector issue - looking for possible solution

cisloui

New Member
Messages
2
Likes
0
City
THORNTON
State
CO
Country
United States
What I Drive
Ford Fusion 2010 V6 3.0L
#1
My 2010 Ford Fusion, V6, 3.0L is continuing to present problem codes P0303 and P0203 related to fuel injection cylinder #3, and mis-fires periodically. Note – the automobile is at 208,000 miles. It is unclear if it is a parts issue, or an electrical issue. Currently, these same codes come up every time I drive the automobile now. They occur immediately, or within 15 miles of driving. It definitely feels like a cylinder is mis-firing. I have made numerous attempts at addressing these codes by replacing parts (coil pack, spark plug, fuel injector) associated with fuel injection cylinder #3 multiple times. In addition, I had the fuel injector connector replaced. The auto repair shop indicated that the part crumbled when touched. It’s my understanding that this part connects the fuel injector to the wiring harness.
Finally, I replaced the ECM earlier this month, and had it flashed/programmed by an independent mobile service. Unfortunately, after about 25 miles of driving the same codes (P0303 and P0203) re-appeared, including the symptoms of cylinder #3 periodically misfiring. Below is a history of repairs trying to address this issue:

2/20/20 – Repaired at initial auto repair shop due to problem code P0303. Note automobile ran good with no issues related to fuel injectors for approximately 18 months afterwards.
  • Replaced fuel injector, spark plug and coil pack for cylinder #3
6/12/21 – Repaired at auto repair shop #2 due to emissions issue with code P0402
  • Fixed emissions issue
8/21/21 – Repaired at auto part shop #2, due to problem code P0303
  • Replaced fuel injector, spark plug and coil pack in cylinder #3
  • Replaced spark plugs in all 6 cylinders
  • Replaced fuel injector in cylinder #1 due to fuel leak
11/18/21 – Repaired at auto repair shop #2 due to problem codes P0304, associated with fuel injector cylinder #4
  • Replaced fuel injector, spark plug and coil pack in cylinder #4
12/13/21 - Repaired at auto repair shop #3 due to problem codes P0303 and P0203
  • Per my instruction, only removed and replaced fuel injector in cylinder #3, installed a new multi-port injector
3/15/22 – Repaired at auto repair shop #3 due to problem codes P0303 and P0203, Note - automobile ran ok afterwards, but presented the same codes again periodically, I would erase the codes, and the automobile would run ok for short periods of time
  • Removed and replaced fuel injector connector #3 and coil pack, note – spark plug had previously been replaced

5/10/22 – I replaced coil pack to cylinder #3

5/16/22 – Diagnosis by auto repair shop #3 due to codes P0303 and P0203. Found – Problem is consistent and can be reproduced during normal road test, or in the service bay. Further tests/work performed during diagnosis:
  • Removed intake manifold
  • Removed and replaced EGR valve gasket, and removed and replaced components as required to access and install materials and/or perform needed service. Restart and verify repair as required. Perform final road test where applicable
  • Fuel injector tested within spec
  • Verified injector wiring harness condition back to bulk head connector, no issues found
  • Verified power, ground and signal on injector circuits, no faults found at this time
  • Due to history, and lack of consistent failure, we suspect ECM intermittent failure
  • Recommend replacement of the ECM with latest Ford software
5/24/22 – I replaced the PCM and had it flashed as directed by an auto repair shop after completion of diagnosis. Note – the same codes came back within 30 miles of driving, and are now appear every time the automobile is driven and the automobile feels like it is mis-firing. Sometimes the code light will go away after a few seconds, or a short time later, and the mis-firing will discontinue.

Just wondering if anyone has any idea as to what may be the issue, is it a simple fix, or should I see about just getting a different automobile due to the miles?
 
Last edited:
OP
C

cisloui

New Member
Messages
2
Likes
0
City
THORNTON
State
CO
Country
United States
What I Drive
Ford Fusion 2010 V6 3.0L
Thread Starter #2
Update on resolution - took the 2010 Fusion to Ford for repair. It was determined that all three wires going from the fuel injectors to the wiring harness had been improperly attached/soldered, thus, creating open circuits. Note - these improper connections after installing new fuel injectors, spark plugs and coil packs were performed by three separate Auto Repair businesses. So I guess, I did not even have to install a new ECM. Note - this will be my last post on this topic.
 


Top