I have a 2005 ford expedition xlt with 5.4 v8(69,428mi) and I have a problem where 90% of the time I drive it I cant go over 2500 rpm. No check engine light or codes at all. when i go foot to the floor in drive it will accelerate to 2500 rpm, stutter and then seemingly stop accelerating until i take foot off the gas and put it back on. Runs and drives great, goes through all gears as long as i keep it under 2500 rpm. is it possibly a faulty o2 sensor or could it be something else?
TIA anyone who can help
make sure the catalytic converter isn't plugged up
any suggestions on the easiest way to do it? live data?
one easy way is to remove the upstream oxygen sensor.
You can also give the cat a bump to see if it rattles inside.
sounds like needs new fuel pump
