hey everybody im looking for some help with my truck. i have a 2001 f150 with the 5.4 v8 ad its having this issue that when you are driving it will stutter around 1800-2300 rpms but then catches its self back up. i cant figure out what it is i have already replaced the fuel filter and the TPS sensor but it didnt help. the weird thing is that it doesnt do it if you drive it nice and easy like grandma to church or if its cold, but if its up to operating temp and you give it some gas it will stutter, im running out of ideas and it hasnt tripped a CEL.

 

Sounds like a low grade misfire. Right around that rpm or around 40-50mph when OD kicks in at low rpms. How many miles on the plugs and cop's?

They can be a pain to pinpoint if your just looking to fix that particular cylinder or if the plugs and ignition have a lot of miles on them, now is a good time to maintain them and replace them. But, on a budget... you can force the misfire by holding it there and hope that it kicks off a CEL and you can pick it up on a scanner. Or a scanner that can retrieve live data will also pinpoint it.

 

How many miles on the engine, how many miles on what brand spark plugs, have any of the coils ever been replaced?

 

Just because there is no CEL doesn't mean there is no code. Scan it for codes. My bet is COP/Plug time.

 

hey guys thanks for the reply's and i hate to say it but i have no idea how old the plugs and coils are i just purchased this truck recently and haven't really had time to do plugs yet but as far as this problem goes i took it up to oreillys and used there scan tool even know theres no CEL and still had no codes so any ideas on how to find out which coil or plug could be bad?

 

There is likely a faulty coil.
To find out which one requires a Scanner to look at mode 6 test 53.
This is the misfire counts on all cylinders separately and will show which ones are the offenders.
These counts accumulate long before any code is triggered.
Good luck.

 

I would replace the plugs on general principle. Use OEM Motorcrafts, no antiseize, torque to 28 ft/lb. Use a bit of dielectric grease in the coil boots.

 

My husband and I have a 97 f150 4.2 liter. We've replaced the fuel pump and fuel filter. We got a brand new battery, replaced the spark plugs, wires, fuses, and relays. We're still not getting any fuel. After doing some research I thought we needed to replace the fuel pump driver module but after even more research found that 2004 and newer actually have that part. Any advice or ideas on what to try next?

 

Welcome to the site.

While you have posted your question in the correct year range, this thread is on the 5.4 motor........way different than the 4.2 you have. To prevent confusion it would be better if you asked your question in either a new thread or in the V-6 forum. You will get answers that are better suited to the problem you are having. Go ahead and start a new thread and I and others will be happy to chime in.

But at this point I'll throw in, have you checked to see if there is fuel pressure at the fuel rail? Also can you hear the fuel pump run when you first turn the key to the run position?

And again welcome to the site.

 

Hey guys just letting ya know got it figured out ran it up to a cousin who has a live scan tool it was a misfire in cylinder 8 so I changed all the plugs and replaced the coil on that cylinder now it runs like a dream again. Thanks everyone for the help and advice.

 

Good job and thanks for letting everyone know what fixed it.