As our 100 series fleet ages we're seeing more ignition coil failures. Is there a certain mileage or age where our 100 series with the 2UZ-FE engine are seeing the need to replace one or more ignition coils?
If you’ve replaced any coils please post any performance differences before & after, along with your millage, years in service and anything that contributing to the reason why you replaced them. Such as age, climate condition, bad spark plugs or improper gap, spark plug tube gasket oil leak, under or over voltage or anything you consider could be a contributing factor.
Sure we need to change coils when we get the P0300 series code suggesting a miss firing coil. Just swap coils to confirm code moves to different cylinder as expected, then replace bad coil. If not confirmed, then work through diagnostic tree.
In some cases we've seen coil replacement correct a poor running engine issue such as rough idle, without the CEL (check engine light) or any code being stored. Can it be that weak coils are robbing us of performance, but have yet to cross the point of giving a code. Would periodic testing with specialize equipment (see: Coil on Plug ignition video below) be a good PM, especially if performance or MPG drops.
Here are some questions to consider:
Rough Idle/Sputtering/CEL/Misfire = Coil pack problems
Understanding Multi-Coil Ignition Systems
Coil-On-Plug Diagnostics: Toyota Tundra - Tomorrows Technician
In the Autolite video below, it's recommend one determine cause of failure and correct it or reoccurrence is likely.
Seem to be three camps on the issue of COP.
1) Replace only dead coil(s).
2) Replace hunting for performance issue without CEL.
3) Replace all 8 as a PM.
Certainly replacing only dead coils will give tangible results immediately, for the least $$ at the moment of failure.
What I find most interesting, are the testimonials of performance issues (running rough and/or low MPG) long before code or CEL reveled a bad coil to be cause. Along with notable improving in performance with those that have replaced all 8. The implication here is, coils do weaken and rob engine of performance, before failing.
We've also seen a few reports of a drop in MPG after changing spark plugs. Could we be damaging coils while removing or could there be some issue with matching old with new??
Which camp are you in and why???
If you’ve replaced any coils please post any performance differences before & after, along with your millage, years in service and anything that contributing to the reason why you replaced them. Such as age, climate condition, bad spark plugs or improper gap, spark plug tube gasket oil leak, under or over voltage or anything you consider could be a contributing factor.
Sure we need to change coils when we get the P0300 series code suggesting a miss firing coil. Just swap coils to confirm code moves to different cylinder as expected, then replace bad coil. If not confirmed, then work through diagnostic tree.
In some cases we've seen coil replacement correct a poor running engine issue such as rough idle, without the CEL (check engine light) or any code being stored. Can it be that weak coils are robbing us of performance, but have yet to cross the point of giving a code. Would periodic testing with specialize equipment (see: Coil on Plug ignition video below) be a good PM, especially if performance or MPG drops.
Here are some questions to consider:
- What are some of the reasons for coil failure?
- Should spark tube gasket, seals & grommet be a PM?
- Should all coils be replace once one fails?
- Should we do a complete coil replacement as a PM at some point?
- Do coils weaken over time reducing engine performance, what the best test to reveal this?
- Aftermarket or OEM coils?
Rough Idle/Sputtering/CEL/Misfire = Coil pack problems
Understanding Multi-Coil Ignition Systems
Coil-On-Plug Diagnostics: Toyota Tundra - Tomorrows Technician
In the Autolite video below, it's recommend one determine cause of failure and correct it or reoccurrence is likely.
Seem to be three camps on the issue of COP.
1) Replace only dead coil(s).
2) Replace hunting for performance issue without CEL.
3) Replace all 8 as a PM.
Certainly replacing only dead coils will give tangible results immediately, for the least $$ at the moment of failure.
What I find most interesting, are the testimonials of performance issues (running rough and/or low MPG) long before code or CEL reveled a bad coil to be cause. Along with notable improving in performance with those that have replaced all 8. The implication here is, coils do weaken and rob engine of performance, before failing.
We've also seen a few reports of a drop in MPG after changing spark plugs. Could we be damaging coils while removing or could there be some issue with matching old with new??
Which camp are you in and why???
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