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My 2004 F150 has been throwing codes. At first it was P0305, P0171, P0320 and P0174. I replaced COP #5 and cleaned the MAF sensor. Now it is only throwing codes P0174 and P0320. Below are the OBD2 readings. I replaced both passenger side (Bank 1??) O2 sensors back in December. Can someone help me interpret the numbers as I really have no idea what they should be? Thanks.
I had to go last weekend so here is more information: The trucks starts and runs normal. The issue I am having is that it will start to buck/stutter/shudder when running at a constant speed, typically somewhere between 45 and 55 mph. I can't tell too much of a difference in gas mileage as it seems to have always gotten poor gas mileage. After posting last weekend, I clean the MAF sensor once again and also cleaned the air filter. I also pulled the negative lead off the battery to reset the codes. The bucking is still present but I haven't thrown any codes yet this week. I've driven 325+ miles thus far. Any ideas or suggestions? Thanks
Which engine? Your long term trims are way too high. Long Ft1 and Long Ft2. Also, you're not showing engine temperature. Is that freeze frame data or numbers that you wrote down while it was running?
I would replace all those injectors with new not reman . They work so hard and they can ruin your engine . Put new sp 546 plugs in with new boots . Use a torque app with android phone and blue tooth reader .They will give you the raw counts per cly that are misfiring . . Torque plugs in 25 to 28 foot pounds .Clean all cop contacts.
You've put a lot in this truck but you got 289k out of it already . A lot is riding on this new reman engine . Engine parts are more important than looks . Is she ain't happy it will look good as a yard ornament only .
You should know how fussy this engine ignition is . Those plugs 5 inches down in head are prime for sparks jumping threw boots to head . Your codes may all hinge on this . Your crank sensor plug may need cleaned for the 320 but misfires can cause this too .
Come back after this and see if we can fix anything left . You may be posting a lot so it would be good if you put 2004 5.4 3v reman @24k miles in your signature line . It helps us plot a fix . You can list what parts are new if you like . A running summary of your fixes is very helpful .
That is freeze frame data. Check engine light came back on today as I was leaving work. Throwing code P0420. All of the spark plugs were replaced when the engine was replaced. Long Ft1 is now reading 11.71% and Long Ft2 is 10.93%. Short Ft1 and 2 is 3.12%. Redfishtd, I have done any more work yet. Where is the best place to buy new injectors? The OEM motorcraft injectors are $93 at rockauto. That seems like alot. Should all of the COPs be replaced with new ones or is it sufficient to just replace the boots and clean the contacts as you suggested? I updated my profile so hopefully my info shows up now.
Edit: The engine info did not show up so here it is: 2004, FX4 with 5.4L remanufactured engine with 24k miles.
Last edited by bengaltiger14; 04-27-2018 at 05:05 PM.
Reason: Add engine info
Of the codes you have mentioned (P0171, P0320, P0174, and P0420), everyone seems to be ignoring P0320 and focusing on the other three. I think I would try to eliminate that one first and see if the others will quiet down. Could be as simple as a 'flaky' component and intermittent and hard to locate - but I think it is most important of all your codes.
P0320 indicates a problem with the Engine SPEED circuit. (Open / short / failed component). Could easily be a 'frayed' wire between the Crankshaft Position Sensor and the PCM, or the CPS itself or the PCM. But if the PCM can't reliably determine engine speed - it lights the CEL and sets a Failure Mode Effects Management (FMEM) and 'defaults' certain sensor readings (IDK which all ones) to try to keep your truck going best it can. I haven't sorted out in my mind what effects that MIGHT have. But certainly if it upsets the Fuel Air measurements and ratio - I can certainly see how you would get P0171 and P0174 as indicated by your Fuel Trims. Run the thing TOO rich with fuel (as LTFT indicates), you will certainly get a P0420 (Catalytic converter below specified efficiency). - It can't neutralize all the unburned hydrocarbons.
EDIT: Another thought. For sure, the misfire code, lean codes, and Cat Efficiency code CANNOT CAUSE the Engine Speed Circuit Failure code.
Last edited by F150Torqued; 04-28-2018 at 09:45 AM.
Reason: AFTERTHOUGHT
your probably correct but online it says it can under OBD2 codes .
f150t--EDIT: Another thought. For sure, the misfire code, lean codes, and Cat Efficiency code CANNOT CAUSE the Engine Speed Circuit Failure code.
---You are more knowledgeable than anyone I know .
I went along with it as maybe the misfire could effect the crank speed and confuse the sensor jerky kind of motion or so .
Plug circuit needs to be ruled out by being first class for the bucking symptoms .. . I agree he should clean the contacts on crank sensor plug and check wiring . I wonder if new reman came with crank sensor and is it aftermarket ,if so I would change it for OEM . . After market seems to have weak magnets in them or so I've been told . .
Crank sensor can cause a lot of trouble .
Tone ring inside can cause sensor problems but this one is fairly new reman -- I'm back to some engines will run poorly with tone ring on backwards others report they won't run at all ???. .. Make sure your airbox foam seal in good shape also . But old injectors worry me .
04-21-2018, 02:03 PM
Need help with codes
