I'm of the opinion that more issues on these engines result from poor connections and sealing than bad coils. I have years of experience with deep plug wells on European cars, and have never had the issues I've seen with my truck. Granted, American manufacturers seem to have more trouble with electronics, but lots of those parts are sourced these days from some of the same subs that the Euro companies use.

I had a mystery misfire that simply came on out of the blue, and turned out to be a bad spring under one coil. The corrosion was not much to look at, and even a little bit will cause a problem. And looking at the factory springs, and the replacements, I think a more robust connector would solve a lot of issues, as would sealing up each boot well, using dielectric grease or even a hi-temp silicone compatible with the rubber of the boot. Poor quality metal connector + moisture is a formula for issues.

 

Hi, I'm new to this forum and new to Fords. I've just bought a Motor Home on an E350 chassis with a '97 V10 engine. I'm having exactly the same low speed miss as described in this thread. I'm wondering if I check the coils impedance with a multi meter what should it be?
Thanks.

 

Don't bother checking them with the meter it's a waste of time because even when bad they most times will still check within specs. If one did check bad then it would most likely be completely dead and would be a constant easy to find miss and that's simply not usually the problem with these things. Since I had that problem we are discussing I have run onto it twice more and it was exactly the same thing and required exactly the same cure, these two however were on V8s but that makes no difference. Those coils can check just fine and still have an intermittent miss, if you go back and read my earlier post I even went so far as to rig up a bench test for these things and still could not detect a problem. Since I had gone to such extremes I simply could not believe the coil pack was bad and was convinced it had to be the boots/springs/resistors but changing them was zero help, likewise a though check for voltage leaking from the pack itself (coil and/or boot grounding/arcing to the engine) turned up nothing. It was not until I bought a couple of new coil packs and installed them one at a time that I finally solved the problem, I have several coil packs lying in a box right now that I would challenge anyone to find a problem with yet they will not work properly under load on the engine.

 

I Finally found Figured out that it wasn't the COP's but the Spring and or Boot you may want to try replacing all the spring and boots or just one at a time I now carry an extra one Also the guys down at the dealer recommend Motor-craft Brand I purchased aftermarket ones and Still had troubles i thing the Boot and coil cost like less that $20 bucks a lot less that complete COP. and stay with Platinum plugs,. Also Torque your plugs on a regular basis like every 10k miles or they come loose and blow right out taking the plug threads in the head,. and Most people will tell you you need new heads but you can get the the re-seated,..

 

Thanks for the replies. I think in view of what's been said I'm going to change all the plugs and all the coils and be done with it.
Has any one got the correct part number for the coils for my engine? It's a '97 V10 in a E350 chassis. I took the dog house off today to see what's involved in changing them and some of them look hard to get at, that's why I think once I start I might as go the whole route at one time rather than try to find the bad one(s) and then have another one crap out on me after a short while. Thanks again for the information.

 

I agree, it's a smart move to do all of them ! I just love spending other people's money. Just kidding though, I believe you made a good decision, Merry Christmas !

 

Keep in mind that OEM COP's are about $90.00 to $100.00 bucks a pop,.. to replace all 10 is about $1000.00 then there is the labor,.. just trying to save you money for about 7k I can get a complete rebuilt engine good for another 150,000 miles so you may want to consider replacing the the whole engine for worry free miles,.. pay now or pay later,..

 

I was going to take a chance on after market COPs which is why I want the OEM part number to make sure I get the right ones. As for the labor cost I am a licensed motor cycle mechanic and doing the job myself will not be a problem other than the inacessability. I realise the after market COPs can be dodgy, but let's face it the OEM ones aren't earning themselves a good reputation!!

 

I have a 2000 F-350 V-10 That the service engine soon light just came on. I took it in for service and was told After computer diagnosis, that the pvc hose was callapsed and needed replacement I said go ahead.
They ordered the part and put it in,Then they called me to let me know that when they fired it up to move it the next mourning to move it ,it was misfiring,So they put it throgh another computer test and that it showed that # 3 cylinder was misfiring and they reccomended to change all wires and plugs at a cost of $577.00 (which I do not have) so I said no. And shure enough when I picked it up and was driving home It is missing and have never had any trouble of any kind with this truck until I brought it in for service light check
What would you do or what do you think?
Thank You

 

This is my first time using this site. Does anyone log on here that can help me ??????????????