03 f250 5.4 jerking at 50+mph
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Converter shudder.
Misfire would make a bigger mess at lower speeds than at higher speeds, but be a mess all over the place.
Misfire would make a bigger mess at lower speeds than at higher speeds, but be a mess all over the place.
On my previous F150, the misfire would only show itself at roughly 45 mph, when right on the edge of needing to downshift to a lower gear or right after shifting in a higher gear. You'd swear it was a transmission problem, but a decent scan showed multiple misfires on one coil. Fix it, and problem solved.
On the Explorer with the V8, it only presented itself under heavy throttle application. Give it an italian tune up, and the misfires would all pop on one cylinder. Replace the coil, and problem solved.
It may seem like if the coil is failing, you should feel it all the time. Reality is it only shows up in certain conditions...
On the Explorer with the V8, it only presented itself under heavy throttle application. Give it an italian tune up, and the misfires would all pop on one cylinder. Replace the coil, and problem solved.
It may seem like if the coil is failing, you should feel it all the time. Reality is it only shows up in certain conditions...
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Originally Posted By: DoubleWasp
Converter shudder.
Misfire would make a bigger mess at lower speeds than at higher speeds, but be a mess all over the place.
My experience with a coil failing on the Expedition was that the problem only presented under periods of higher load at lower RPM. If I hit a grade, it would start to miss, get it to downshift, the miss would go away. Driving normally, it wouldn't miss. Since it never triggered a CEL, we had to use a scanner that could read the misfire counts to determine which cylinder it was.
Converter shudder.
Misfire would make a bigger mess at lower speeds than at higher speeds, but be a mess all over the place.
My experience with a coil failing on the Expedition was that the problem only presented under periods of higher load at lower RPM. If I hit a grade, it would start to miss, get it to downshift, the miss would go away. Driving normally, it wouldn't miss. Since it never triggered a CEL, we had to use a scanner that could read the misfire counts to determine which cylinder it was.
Pull codes first before you spend a penny.
Just because there is no MIL, it doesn't mean there is no code. You should luck out and get a cylinder misfire code which will verify the concern, and tell you what cylinder is the problem. The problem occurs when cylinder pressure is the highest, and voltage requirements are the highest, or right when you get into high gear under part throttle....and when the converter locks up.
Converter shudder and misfires can often feel the same. I have been fooled a couple of times in the shop.
Just because there is no MIL, it doesn't mean there is no code. You should luck out and get a cylinder misfire code which will verify the concern, and tell you what cylinder is the problem. The problem occurs when cylinder pressure is the highest, and voltage requirements are the highest, or right when you get into high gear under part throttle....and when the converter locks up.
Converter shudder and misfires can often feel the same. I have been fooled a couple of times in the shop.
In my case, it would present the symptoms for months and thousands of miles of driving before throwing a code. Honestly, it was very frustrating to try and track down.
Using torque pro and a bluetooth adapter, I was able to do individual cylinder misfire counts, identify the culprit and replace long before any code would be thrown.
Using torque pro and a bluetooth adapter, I was able to do individual cylinder misfire counts, identify the culprit and replace long before any code would be thrown.
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