Misfire count

I'm wanting to find a misfire count on the expy, but the mode 6 TID's are limited on the 2003 as compared to later model years. Using 'OBD Car doctor App' and the Mode 6 function, I found data points labeled 'Manufacturer Specific' that I think may be misfire counts, as there are 8 component ID's for that TID.

Would you assume these are misfire counts by the data and the maximum value of 15616? Would Forscan better display this information?


I recently got a P0430 code, and have noticed an occasional mild-stumbling idle, so I'm wanting to eliminate misfires as a potential cause. If i should be starting somewhere else, please speak up.

Answering my own question here, but this might help someone later or give you a push to try out Forscan. I finally got around to installing/connecting Forscan and it immediately showed me the misfiring cylinders, 6 and 8.I found that Forscan gives a much better description for all of the Mode $06 data.

Now onto fixing my problem.. The plugs are only 3 months / 1,000 miles old, but the cop's & boots might be original from 2003 & 212k miles ago. I'll pull the plugs first, and if torque, plug and boot still look good, I'll swap coil packs with 5 & 7 and go from there.

Who knows if curing the misfire will solve my p0430 (that hasn't returned since I cleared codes), but i figure it's a good start.

You might want to replace just those 2 plugs instead of re torquing them. The plugs even fairly new can contribute to your misfire. Carbon and arcing builds around porcelain, not to mention the plug itself on the nose end gets a lot of punishment. Figure your in their already, why not? Good idea on coil swap around. If it turns out to be a bad coil, you know just change those 2 along with the eight boots of others. The boots break down when they get old, sorta like an older style spark plug wire does.

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Hey Moose. Great thought on replacing the plugs, for the cost I would've done it that way had I thought of it before. I pulled coil and plug from #6, coil has primary resistance of 5.33k ohm and secondary resistance of 0.8 ohm, so no direct short from what other people are noting, and plug looked good. For now I swapped coil #6 with coil #1 to see if the problem follows. I left the other (sometimes) misfiring cylinder #8 alone for now, trying to only change 1 thing at a time and test again. Except for the grime, the boots looked and felt good, I am now assuming the boots are not original or they would be hard and brittle.

Those reading are fine on the coil. Wished more members here would do the ohm readings, it's so simple. I'm betting you've got worn boots on those coils. Let us know how it turns out. What brand of plugs did you put in there? A lot of the plugs except Ford and Bosch seem to misfire.

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Plugs are motorcraft, from recollection sp549,or something like that. I’ll get some miles in tomorrow and report back on the misfire

Bain64 said:

Answering my own question here, but this might help someone later or give you a push to try out Forscan. I finally got around to installing/connecting Forscan and it immediately showed me the misfiring cylinders, 6 and 8.I found that Forscan gives a much better description for all of the Mode $06 data.

Now onto fixing my problem.. The plugs are only 3 months / 1,000 miles old, but the cop's & boots might be original from 2003 & 212k miles ago. I'll pull the plugs first, and if torque, plug and boot still look good, I'll swap coil packs with 5 & 7 and go from there.

Who knows if curing the misfire will solve my p0430 (that hasn't returned since I cleared codes), but i figure it's a good start.

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I also have a 2003 EB Expy. What device did you use with the Forscan App/Program IE is it a simple OBDII BT or Wifi dongle? Was Forscan installed on a laptop or did you use an App with a smart phone? I have an older Big Banana OBDII reader and a newer OBDII BT dongle. I like the dongle because I can just leave it plugged in and get true live data. I can leave the Big Banana plugged in, but the cable and its larger body are in the way no matter where one puts it.

As for plugs, why chance it or bother taking one out and putting it back in? At $3 to $10 depending on if using Iridium or Platinum, it is easier and better to just replace any plug that is removed eliminating it as a possibility.

As for the COPs, if they are original ones that are 15 years old with 212K miles on them, it is long past time for them to go. The boot is no longer a good insulator and probably has micro cracks in it you can't see where the spark is occasionally shorting to the block causing a misfire. If I have a new COP and OBDII data says something is wrong with cylinder 1, I will swap, but if the COP has 30K or more on it, it is gone. COPs are not that expensive if one doesn't get them from Ford or an auto parts store (I use Ebay and Amazon to buy them by the dozen or 10 pack as the 5.4L uses the same COP as the 10 cylinder Ford motor). How do I know what is what, I track my COPs and Plugs on my smart phone using a simple Note. I have a note with the title of each car: Expy, T-Bird, Stang, Explorer on my iPhone and then I have a list of each cylinder with the mileage of when any COP or Plug was changed. Not a true Ford fan, but some how I even up with all Fords.

Not a true Ford fan! 5 Ford's in your garage, and driveway, Transporter, were going to have to check you in to the Henry Ford clinic! I've been buying Ford's and Lincoln's since 1986. 3 mustangs, 2 Lincoln's, and my current Expedition. Next will probably be F150 Lariat 5.0.

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Sorry only 4 for transporter, theirs hope for him. I don't know about you guys, but my Ford's always seem to get me home, even when wounded. That's reason enough to be a faithful.

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Misfire moved from cylinder 6 to 1 after I moved the coil from 6 to 1. Two Motorcraft coils have been ordered for delivery Tuesday. I'm debating performing a similar test on the other misfiring cylinder (8), but might just replace it and go from there.