Sterling Archer
Well-Known Member
Ok, my ride has 238,6xx miles on her. Had started missing/hesitating at most all rpms (rough idle, but not in danger of stalling with constant little surges at cruise). Last week I had new plugs installed (Motorcraft), the shop also replaced two COPS on the right bank, front two cylinders.
Ran fine for 2 days then developed a misfire and codes as above. Took it to autozone to scan (My scanner is packed away somewhere...) And the kid said ALL but one cylinder was misfiring (Don't recall which one.).
I order a cheap set of COPs on Amazon and replace all BUT the 2 my mechanic replaced. Ran better but still misfire in #7. Removed COP to replace with an extra I had not used and saw I forgot to put dialectric grease the one I had put on. Put a gob in the boot of new COP #2 as well as the harness connector (for all of them). Ran MUCH better. Thought I had it licked. Multiple COPS on cylinder, same problem...
Today it starts up again..MUCH more noticable. Got coded for P0307 AGAIN.
No visable coolant leaks or smells, no vacume leak sounds/hisses, oil changed 2 months ago looked fine. Research says bad cam/crank sensor would keep engine from running at all. I see NO arking/spark leakage at boots.
ALSO, possibly unrelated but notable...on a cold start, it sounds like I have an exhaust leak on right bank BUT after 30 seconds or so....it goes away. Been going on for some time but even before the misfire, did not seem to affect drive quality. Doubting cracked header as it would sound awful all the time and not heat up in 30 sec to expand and seal itself.
Doubting vacume leak or low compression due to on-again/off-again nature of problem.
I am leaning towards a bad injector(s). With 238k+ the internal screens may be plugged or pintles sticking. Ran a heavy dose of gumout FI cleaner for a full tankfull (done over 4 days). New pump was put in tank 2 years ago (at about 170k), inline filter is still original but will be changed this weekend just for ***** and giggles.
I can get remanufactured set of 8 bosch injectors from ebay for $100. Worth the chance? Is there a special tool to remove/install? Best way to relieve fuel pressure?
Comments? Thanks!
Ran fine for 2 days then developed a misfire and codes as above. Took it to autozone to scan (My scanner is packed away somewhere...) And the kid said ALL but one cylinder was misfiring (Don't recall which one.).
I order a cheap set of COPs on Amazon and replace all BUT the 2 my mechanic replaced. Ran better but still misfire in #7. Removed COP to replace with an extra I had not used and saw I forgot to put dialectric grease the one I had put on. Put a gob in the boot of new COP #2 as well as the harness connector (for all of them). Ran MUCH better. Thought I had it licked. Multiple COPS on cylinder, same problem...
Today it starts up again..MUCH more noticable. Got coded for P0307 AGAIN.
No visable coolant leaks or smells, no vacume leak sounds/hisses, oil changed 2 months ago looked fine. Research says bad cam/crank sensor would keep engine from running at all. I see NO arking/spark leakage at boots.
ALSO, possibly unrelated but notable...on a cold start, it sounds like I have an exhaust leak on right bank BUT after 30 seconds or so....it goes away. Been going on for some time but even before the misfire, did not seem to affect drive quality. Doubting cracked header as it would sound awful all the time and not heat up in 30 sec to expand and seal itself.
Doubting vacume leak or low compression due to on-again/off-again nature of problem.
I am leaning towards a bad injector(s). With 238k+ the internal screens may be plugged or pintles sticking. Ran a heavy dose of gumout FI cleaner for a full tankfull (done over 4 days). New pump was put in tank 2 years ago (at about 170k), inline filter is still original but will be changed this weekend just for ***** and giggles.
I can get remanufactured set of 8 bosch injectors from ebay for $100. Worth the chance? Is there a special tool to remove/install? Best way to relieve fuel pressure?
Comments? Thanks!
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