mgrana3 Posted November 15, 2005 Share Posted November 15, 2005 I have a 03 f-150 with a 4.6 ECC test dtc po175. normal diagnostics have not revealed cause .New pcm,exhaust ok, plugs and coils ok,fuel pressure ok ,no leak down,injector flow ok,evap unplugged from intake, does anyone have any ideas. Im starting to think it might be intake runner restriction all cylinders on bank 2 are missfiring on powerbalance test. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 15, 2005 Share Posted November 15, 2005 I voted for 1... now whether this was the popular vote or not, I can't tell... but I thought it was better than the other choice /forums/images/%%GRAEMLIN_URL%%/wink.gif Do your fuel trims give any hints? Had a 3V 5.4 with a plugged cat.... caused by a hole with a broken valve spring... No misfire codes. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 15, 2005 Share Posted November 15, 2005 Would you like help with the poll? We can delete the thread before it goes far and start fresh if you would like. /forums/images/%%GRAEMLIN_URL%%/shrug.gif Quote Link to comment Share on other sites More sharing options...
mgrana3 Posted November 16, 2005 Author Share Posted November 16, 2005 yes keith browning I Did not really understand the poll procedure. Quote Link to comment Share on other sites More sharing options...
mgrana3 Posted November 16, 2005 Author Share Posted November 16, 2005 Jim Warman, the fuel trims I read are as follows, long1=10-14, long2= -28, short1=.2-4, short2= -15 or somewhere around these figures. The cats seem to be fine. I Removed cat from bank 2 ran power balance bank 2 still down. Quote Link to comment Share on other sites More sharing options...
ktmlew Posted November 16, 2005 Share Posted November 16, 2005 Did you run relative comp test? Maybe you have a base engine concern. Seems odd it would affect all cyls on one bank but??? Quote Link to comment Share on other sites More sharing options...
Torqued_Up Posted November 16, 2005 Share Posted November 16, 2005 I agree about the base engine concern if the intake runner idea checks out okay but I thought those had position sensors? Hey, I'm a diesel guy what do I know! Did you run a relative compression test that might indicate a cam timing issue? Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted November 20, 2005 Share Posted November 20, 2005 Those trims look pretty close to what I had with the plugged cat... the affected cat was almost cold to the touch. Other than that, Eds cam timing issue has merit (but I can't remember which side the CMP is on, for some reason). Now that he mentions it, I did have a failed VCT actuator on a 5.4 some time ago... I had codes to work with so I didn't go beyond that but it did run like it had about 4 bad cylinders. Interestingly, the same truck had a bad upstream O2 heater on the same bank. Quote Link to comment Share on other sites More sharing options...
truck_guy Posted March 11, 2006 Share Posted March 11, 2006 I had 3 f150's and 4 expeditions with 4.6l and 5.4l 2v and 3v engines with codes p0172,p0175. Thank god they didn't all come at they same time. Any way after pulling my hair out I figured poor quality. After arguing with the service manager and explaining that it is a cp job. I took off the intake manifold and all the spark plugs, soaked intake valves with ford pm2 carb cleaner and scurbbed carbon build up on valves and intake ports. that finally cured my problems with those codes. Watch fuel trims closely. Ford Senior Tech Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted July 9, 2006 Share Posted July 9, 2006 Ford's modular cam timing problem is as follows: 1 tooth off vehicle idles rough but runs great off idle, 2 teeth off runs rough all time, 3 teeth off you bend stuff. I've seen many of em right from the factory one tooth off. You kinda have to bite the bullit to check it though. Quote Link to comment Share on other sites More sharing options...
pcassidy111 Posted August 7, 2006 Share Posted August 7, 2006 What is the o2 sensor doing? Have you confirmed that bank 2 is actually rich? If you create a vacuum leak can you get the bank 2 o2 sensor to go low? Is the o2 sensor plug covered with oil, allowing voltage from the o2 heater to bleed over to the o2 signal wire? No moisture or other contamination in the loom plugs causing voltage to 'leak' over to the o2 sensor wire? Had a truck one time that had transmission work done and they switched the o2 sensor plugs-caused wierd problems. Had another truck that had a tranny done and they did not put the o2/transmission wiring back properly, melted on the exhaust and caused a low voltage (around 1 volt) to be applied to the o2 signal wire-indicating a rich mixture and causing a lean miss. Quote Link to comment Share on other sites More sharing options...
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