we'll I'm glad I decided to re-visit F150 online. Just walked in from the garage and you guys have a possible instant solution for my problem. Similar to OkCarr1966. Misfire codes on multiple cyl. cleared codes and mis fire on 2,6,&7 with Lean bank1 rich bank2. Changed the plugs and same result with no codes?? Barely idles at 600RPM, back fires, give it gas and just about dies, revs with unstable rpm at constant throttle level. lots of grey smoke and un-burnt fuel.

Truck sat for 4 months until it was warm enough to rebuild the front suspension. Finished front suspension up and the truck drove like day 1!...for a week!

Any additional feed back or insight is welcomed.

W

 

2004 F150 FXR 5.4L Scab w/265000KM about 165000Miles. starts with difficulty idling and mis-fires / back fires with increased throttle. Changed plugs using Ford Sp515. Spark is only one part of the system has anyone incurred the same issue that was resolved from a fuel & intake/exhaust issue? Block cats? Vacuum leak? dead sensor? trying to diagnos without continually throwing money at a solutions. Spending money on the correct diagnosis not a concern.
- how to check vacuum leaks on the 5.4?
- How to check fuel pressure on 5.4?
- how to clean throttle body?

There is likely tech articles buried in the wealth on knowledge on this site, however hoping someone can point me to the correct forum / link.

Thanks in advance for assistance.

W

 

88, I moved your post out of the Exhaust forum to this one, where you first posted this problem. Please don't create multiple threads on the same subject - it causes confusion that can lead to misleading responses. And, don't hijack an existing thread with a new problem. It can keep the Original Poster from getting the help he needs.

You didn't say what brand plugs you installed. Anything other than Motorcraft can cause problems. Also, what are the condition of the COPs? Your symptoms really sound like ignition problems to me.

But, if the truck sat for four months, the fuel could be degraded too.

- Jack

 

Thanks Jack & Janet. Impatience, compounded with sourcing common thread related to problem. No hi-jack or misleading intended. Motorcraft SP515 plugs, COP appear to be in good condition. proceed to clean MAF and TB tonight, same result. My concern with replacing the COP(s) is that the codes read misfire on Cyl 5 & 7. Move/swap COP around to duplicate code on the an alternate cyl. Ie COP#7 to #2 if COP bad the new code should have been P0302. #2 did not code.
Original codes:
P2195- O2 stuck lean Bank 1 Sensor 1;
P0308;07;06; 05; misfire
P0300- multiple mis fire
P0175 - Bank to rich
P0171 B1 to lean
P0022 Cam shaft positions sensor timing over retarded.
P2198 O2 stuck Rich Bank 2 Sensor 1.

Clear codes/re-started truck

returned P0300; P0307; P0305; P2198

Any suggestions are greatly appreciated.

Warren