I have a 2001 F150 Lariat 5.4l. When you go to accelerate it starts jerking, loses power under load, low fuel efficiency, rough idol very rough plus much more. Replaced the fuel pump, coil packs and plugs, mass air flow sensors and the EGR along with water pump. Still having same issue but seems to be getting worse”if possible “! Any suggestions or maybe same issue and you figured it out? 🙏

 

Well, it seems it's time to conduct actual diagnostic testing.... 1) what codes do you have? and 2) did you use oem replacement parts?

 

The PCM won’t communicate with the scanner. It would make things easier. Checked all fuses and relays but no luck. I’m desperate
Fuel pressure is between 35-45

 

If you haven't, You need to check fuse #3-20amp in central junction box under left side of dash. That fuse is the power source for the data link connector and cigar lighter. The cigar lighter often blows the fuse when objects are plugged in.

 

PCM coms is also an issure.
Look at the pins to see if one is bent or pushed back.
The Cigar lighter circuit is on with the plug power needed to power the Scanner .
You cannot fix a complex problem by throwng parts at it..
Diag. first, repair second.

 

Unfortunately I’m not able to get in with FORD till next Wednesday so the items replaced were suggestions from them . They are thinking a new ECU or reprogrammed. But yes diagnositic test would be great.