falls on its face when warmed up
#1
falls on its face when warmed up
I have a 1996 Ford F 150 XLT with a 5.8 351 Windsor and I e4od transmission. When i go to start it it takes a little while to start but it will run fine for little bit but when it warms up it acts like it not running on all cylinders. I have already replaced the timing chain and gears, and the ignition control module and got a new distributor, new plugs, new wires. a new coil, and it's got to MSD cap and rotor, but the cap and rotor is like a year and a half old, and I'm getting good fuel pressure, and I'm out of ideas
#2
First things first, pull the codes. Even if the CEL isn't on, if it's running that poorly, it probably has some stored. A bad O2 sensor could do that, but so could a lot of other stuff. FWIW, the O2 sensors aren't overly fun to replace on those. Bank 1 isn't too bad, but bank 2 is tucked in there pretty good. A fuel pressure test would probably be a good idea too.
#5
Check for spark on all cylinders. At the same time, you can identify a dead cylinder. Take one spark plug off at a time while the engine is running and check for spark. If you don't get a change in idle, that cylinder isn't contributing as the others are.