SPONSORED LINKS

Truck was misfiring on 3 cylinders

Tiny
ANONYMOUS
  • MEMBER
  • 1997 FORD F-150
  • 179,000 MILES
Truck was misfiring on 3 cylinders. Did tune-up with motorcraft plugs and wireset. Replaced fuel filter and air filter. Test drove truck and was worse. Hard stutter under load and throttle. More truck drove more rough idle became. Became hard to start. Scanned once more and found code P0174 bank 2 lean. Scan tool shows no misfires or faults in injectors. Check engine light not on. Did KOER and KOEO tests and only the P0174. Tested EGR system. Checked for vacuum leaks. Tested mass air flow. Replaced 3 O2 sensors. Tested fuel pressure. 37 psi at key on and 31 psi when running. Truck has 4.6L vin w engine. Need help bad.
SPONSORED LINKS
Wednesday, March 13th, 2013 AT 8:20 PM

1 Reply

Tiny
CARADIODOC
  • MECHANIC
  • 33,916 POSTS
A lot of people solve this code by replacing the EGR valve assembly. Also check for passages blocked with carbon. Those are the cylinders that will run well because they're only getting fresh air and fuel. The full EGR flow will go the cylinders that aren't blocked making them misfire.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Wednesday, March 13th, 2013 AT 9:03 PM

Please login or register to post a reply.

Related Mass Air Flow Sensor Test Content

VIEW MORE

Sponsored links