2001 Ford F150 2001 F150 running rough......help!!!

2001 FORD F-150
199,000 MILES • V8 • 4WD • AUTOMATIC
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PATTHORSSEN
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Hi, I started my truck yesterday and it idled good, but when put in gear felt as though it was missing and also while driving, especially in OD. The SES light started flashing and then stayed on. I checked the code with my Hypertech PPIII and it was P0125, Insufficient Coolant Temperature to enter Closed Loop, so I replaced the thermostat, the temp sensor, and since it had 199000 on the original plugs I replaced them too while I was at it. It still "misses" badly so I suspected the COP's and went through and unplugged them one at a time while the engine was running and believe they are all throwing spark, by the way each missfire code showed up as they should for each cylinder when I did that. Now the code P1000, OBD-II Monitor Testing Incomplete, came up and I cleared that. I am now suspecting an injector may be partially clogged? I'm thinking that because while driving it today it seemed to work itself out of the problem once in a while and run great, but then would continue to "miss". I'm also thinking I should replace the O2 sensor. A local mechanic suggested my MAF sensor may be bad so I cleaned it with no effect. What is your take on the issue? What would be the best way to clean the injectors? Is it possible that one of the coils could be weak? This is the first time this pickup has ever had any problems so I cant complain too much about it! Thanks for any thoughts.
[img:abe36b78f6]http://www.2carpros.com/forum/automotive_pictures/350966_big_boys_love_big_toys_2.jpg[/img:abe36b78f6]
Big boys love big toys!
May 1, 2009 at 11:12 PM
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MERLIN2021
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https://images.2carpros.com/forum/automotive_pictures/62217_150p0125_1.jpg

Check cylinder head temp sensor, if all else checks out.
May 2, 2009 at 7:38 AM
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PATTHORSSEN
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I replaced the CHT sensor along with the thermostat the other day, after doing that P0125 hasn't come on, but its still running rough.
May 2, 2009 at 8:48 AM
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MERLIN2021
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Have you cleaned the throttle body lately? Use only tbi cleaner with engine OFF.
May 2, 2009 at 9:05 AM
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PATTHORSSEN
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I cleaned the throttle body with no noticable difference in how it ran. I also repaced the fuel filter. While driving it yesterday P0301 came up so I installed a new cop on #1, but the code came back, then I swapped injectors with #3, just as a trial and error to see if P0303 would display. No codes showed and it still ran with a miss. This morning now I went and started my pickup and it ran terrific while I drove it a ways on a local highway. About 25 miles later is started "missing" again. It's starting to get to the point where I dont know what else to do, while driving it still "comes out of it" at times and runs great. I'd hate to have to bring it to a garage, but at this point I may have no other option unless someone has an idea.
May 3, 2009 at 4:22 PM
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MERLIN2021
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Check the ground on the passenger side under the hood at the firewall.
May 5, 2009 at 1:46 PM
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