Hi all,
New Member long time ford owner! I just picked up a 2006 F250 with the 5.4 3v and need some help analyzing my freeze frame data. The truck is misfiring, idling bad on deceleration and lacking power. if it sits in park it idles very good. It also pops out the intake and I've read this is caused by a lean condition or stuck valve. Ive spent the last week scouring forums looking for the answers to my problems. Ive read a lot on the 5.4 and have replaced the following-

New Coils
New MAF
New Fuel Filter
New Air Filter
I Triple checked all vacuum lines
compression was done by PO
and was 180psi on all cylinders passengers side and 145 on all cylinders drivers side

It still throws random misfire codes and cylinder specific misfire codes as well as lean codes

I ran freeze frame but don't know what to look for when it comes to fuel trim etc. Im hoping someone can enlighten me as to what this data is telling me or if there is anything obvious that jumps out at them. Tomorrow I may pull the Cats as a last ditch effort to get this truck running right!

Here is the FF data

DTCFRZF P0303
FUELSYS1 CL
FUELSYS2 N/A ?
Load PCT % 46.7
ETC (Celsius) 73
SHRTFT1 -2.3
LONGFT1 -16.4
SHRTFT2 7.8
LONGFT2 8.6 ?
RPM 659
VSS 0
SparkADV 25
IAT (celsius) 22
MAF 4.65
TP% 13.3 ?
02B1S1 .290
SHRTFTB1S1 % -2.3
02B1S2 .810
02B3S1 0.065
SHRTFTB3S1 % 7.8
02B3S2 .795 ?
RunTM sec 1384
FRP (KPA) 302.333
EVAP_PCT% 39.6
FLI% 14.9
WARM UPS 0
CLR DIST 0
EVAP VP (PA) -77.25
BARO KPA 73
CATEMP11 (CELSIUS) 503.20
CATEMP21 (CELSIUS) 503.20
VPWR (V) 14.263
LOAD ABS% 28.9 ?
EQ RAT 0.999
TP R 1.2
AAT (CELSIUS) -3
TP B% 15.3
APP D% 19.6
APP E% 29.4
APP F% 18.8
TAC PCT% 2.0

Thanks!!!

 

I've had two 06' 5.4s and replaced both throttle bodies.

 

We're you having similar symptoms? From all the research I've done, none has pointed me in the direction of the throttle body. Intake manifold maybe but not TB. Could you please elaborate?

 

I honestly don't remember, I'll check to see if I can retrieve codes from my scan tool.
Neither had the backfire, they would just shut off.
Often throwing wrench but no check engine light everytime.

 

It's not the throttle body. That would affect all cylinders equally, not just one cylinder or side of the engine.

 

I think your compression results are telling. The fact that you're misfiring on the same bank that was showing low compression supports that.

So why low compression? The fact that an entire bank is showing low compression suggests a common cause. All four cylinders share a camshaft, and that's controlled by a notoriously unreliable VCT system. Thinking your issue likely stems from the VCT system failing on Bank 1.

 

I thought about that. I wonder if it's out of time. Even if it's never been apart, it could have been built out of time. Low compression on one bank is extremely suspicious.

I think it could never be out of time enough to backfire through an open valve. It would have to be backfiring because the valves are too hot, and I think that is still a possibility.

 

I will have to confirm the compression results as this info was from the previous owner. I had the plugs out today but didn't have the right end for my compression tester. Plugs were a little black and didn't look like they were removed from a bank running lean. I do get misfire codes 303, 308 on both banks and a random misfire 300