Felt like a coil pac, with all of them that went on my F350 thought I recognized it as a coil pac consumer pro!
Went to shop. Computer said 2 bad coil pacs, replaced them and 2 plugs
6- 8 miles later, missing just as bad.
Took it back. Another old coil and the new one they put in cyl 7 bad? They figured defective as new so replaced it again. Also had all 8 plugs done. 7 is the bad one, think 2 or 4 and 6 were the others replaced.
Left the shop, missing mildly but couple miles bad miss again.
Talked to 3 mechanic garage owners and my shops owner about it. Suggestions were, burnt valve (don't think so, too erratic and just came on) but a full compression check tomorrow to satisfy that aspect
Suggestion, "sea foam" in gas, possibly and injector. 158,000 miles on it.
Take it out of OD and drive, less load less bad miss. But certainly there. Noticeable at idle and uphill mostly.
One shop owner mentioned (yea they all hang at eachothers places) I had a catalytic code of 420 on one side and 430 on the other. Manifolds meet in a Y right of the bell housing and replaced with a tube.
Hopefully just an injector for the miss. With the P0420 and P0430 the cats are done. Often if a vehicle is driven with a misfire the cats burn up because unburned fuel leaves the combustion chambers and burns in the cats. This is why the check engine light is made to flash for misfire issues instead of just staying on solid.
If not related to an injector or spark, there are other things that can cause an intermittent miss (like a broken valve spring) which would be much better news than a burnt valve... Unless it drops the valve, in which case it would be worse. Other things that could cause intermittents would be the circuitry to the coils and injectors.
Another thought... If it has variable cam timing there are things that can cause an entire bank of cylinders to start missing. The Ford 3v engines for example can develop an issue where the cam bearing surfaces wear out (especially for people that go more than 5k between oil changes). When this happens oil pressure bleeds down through the cam bearing surfaces when the engine reaches operating temperature and there isn't enough oil pressure to operate the cam timing phasers. This in turn causes the valve timing to become very retarded and it will start missing on an entire bank, or even both banks. This issue generally doesn't show until the engine warms up, then you get misfires on several cylinders. In the case of the Ford 3v engine the fix is a long block, because the cam bearings are not replaceable and 2 new heads with labor is about the same as a long block. Hopefully this isn't your issue.
Also, I've never had a computer tell me that coil packs were bad. I've had a computer tell me there was a misfire flagged to a specific cylinder, and I've even seen a code for specific ignition primary circuits... To my knowledge there is no code that indicates "bad coil." That determination would require further testing, and I fear you may have already purchased some parts that weren't needed because said "further testing" wasn't done.
-- Edited by PowerStroker on Tuesday 24th of July 2018 09:54:01 PM
Could also be something as easy as a coil boot or the spring that is inside of it. Also it helps to put a little dielectric grease at the base of the coil boot to ensure the spark does not escape and ground. The boot could also be bad too, leaking or should I say grounding out.
Let us know what you find!
__________________
What is to give light must endure burning -- Viktor Frankl
Hopefully just an injector for the miss. With the P0420 and P0430 the cats are done. Often if a vehicle is driven with a misfire the cats burn up because unburned fuel leaves the combustion chambers and burns in the cats. This is why the check engine light is made to flash for misfire issues instead of just staying on solid.
If not related to an injector or spark, there are other things that can cause an intermittent miss (like a broken valve spring) which would be much better news than a burnt valve... Unless it drops the valve, in which case it would be worse. Other things that could cause intermittents would be the circuitry to the coils and injectors.
Another thought... If it has variable cam timing there are things that can cause an entire bank of cylinders to start missing. The Ford 3v engines for example can develop an issue where the cam bearing surfaces wear out (especially for people that go more than 5k between oil changes). When this happens oil pressure bleeds down through the cam bearing surfaces when the engine reaches operating temperature and there isn't enough oil pressure to operate the cam timing phasers. This in turn causes the valve timing to become very retarded and it will start missing on an entire bank, or even both banks. This issue generally doesn't show until the engine warms up, then you get misfires on several cylinders. In the case of the Ford 3v engine the fix is a long block, because the cam bearings are not replaceable and 2 new heads with labor is about the same as a long block. Hopefully this isn't your issue.
Also, I've never had a computer tell me that coil packs were bad. I've had a computer tell me there was a misfire flagged to a specific cylinder, and I've even seen a code for specific ignition primary circuits... To my knowledge there is no code that indicates "bad coil." That determination would require further testing, and I fear you may have already purchased some parts that weren't needed because said "further testing" wasn't done.
-- Edited by PowerStroker on Tuesday 24th of July 2018 09:54:01 PM
Thanks fot the info Powerstroker, I'm thinking injector the way it acts. Agree, spring could be much easier! 2 were missing on one side and one on the other. Seems to always point to #7 so focus of my thoughts right now.
Correct, sorry I worded it wrong. Code shows a misfiring cylinder.
Could also be something as easy as a coil boot or the spring that is inside of it. Also it helps to put a little dielectric grease at the base of the coil boot to ensure the spark does not escape and ground. The boot could also be bad too, leaking or should I say grounding out.
Let us know what you find!
Was thinking on the boots myself, as a hunch gut feeling. I have dielectric grease too and I can check that and boots myself. Mechanics here are pretty good, good prices on parts, $35/hr and don't charge the whole hr if they work a half.
I don't know these engines at all, but if it is EFI ( Electronic Fuel Injection ) each injectors electrical plug connector can be disconnected whilst the engine is running.
*Remove & replace each connector one-at-a-time with the motor running.
*When you notice NO difference to the way the car runs with one-of-these connectors ( or more ) unplugged, that will be your faulty cylinder(s), & where you can start investigating further...
From here, you can swap over coil-packs & injectors to the dodgy cylinder, to determine the faulty component, as it will start working again, & the fault will be moved to the cylinder where you sourced the change-over-part.
Good luck, fingers crossed you don't need a valve-job or new springs, as usually everything gets done in the one repair process, & that can be expensive...
Put real simply, swap parts from one cylinder to another & see if the problem moves with the changed part.
Cheers,
Rastus
__________________
"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together". Dwight D.Eisenhower.
Thank you Rastus, not having a computer code reader that is my only way!
OK. Took it in this AM for a compression check but the mechanic found the problem in 3 minutes. Broken wire at the injector for #7. Seems toyota in MA screwed her truck major. Frame recall 2012, 2 1/2 months, cost toyota 11K and 2 1/2 mo giving her a brand new silverado. Nothing worked after the frame. The cut an injector wire, spliced in the alarm siren. Only the splice was copper to copper with a piece black tape. Corroded and gave away.
GM & Toyota joined forces here a while ago...Maybe ongoing, but not sure, & probably not likely now, as they both have pulled-the-pin on local manufacturing...
__________________
"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together". Dwight D.Eisenhower.
The Ranger was also sold as the B2000 pickup, Probe was a MX6, and there have been a lot of shared components even within their exclusive offerings ie: engines, transmissions etc.
Ford also did a very icky joint venture with Nissan and for a while was selling Nissan Quest vans that were rebranded to be Mercury Villagers.
Ford at one time owned more than 30% of Mazda, but I think they are now down to around 10% or so.
