Issue on my 04 Ford Expedition 5.4L
Can you guys help me narrow down my options. I pulled a code and it said too lean bank one. However I was suddenly getting better fuel economy, so I ignored it. Yesterday the check engine light started flashing, so I pulled the codes again, this time, one and two were lean. Now the exhaust sounds like I just added headers.
I guess it could be weak fuel pump, dirty MAF sensor or injectors, vacuum leak.
I was hoping with my symptoms you can tell me where to start looking.
Thanks in advance for the time saved.