Performance degradation over time

Z

Zhehan

Member
You know, that stuff is insidious. You just get used to it without realizing.

I was past due on the replacement interval for the coil packs by quite a few (100,000 :wtf:) miles. Shame on me. But, the truck ran "fine". I should have replaced them when the Igniter died in February. Anyway, I replaced the 3 coil packs yesterday and holy moly what a difference.

There is so much more power and torque below 2K RPMs now. Partial throttle acceleration is super good. I'm kicking myself for not doing this sooner. I expect an improvement in fuel economy as well. I have a beach trip this weekend so I'll be able to track some good highway mileage.

Do not ignore the maintenance intervals. Lesson learned.
 
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Interesting - I did not know a coil pack had a replacement interval. Mine are original at 352K LOL.
 
100K is the recommended interval. I probably shouldn't say this on this forum, but I went with the "Import Direct" brand from O'Reilly's. They come with a lifetime warranty and have great reviews. I've purchased other items branded as such and they've all been really good quality items. The coil packs are $63.99 each at my local store in Oregon. The Densos are $107.99 w/ a 12 month warranty. As I said, they made a really noticeable, positive difference. I would be surprised if you didn't notice a difference if you replaced yours. I had replaced the boots before and that was an improvement because those are a wear item as well.

My .02
 
Funny you mention this now, as I was just about to order up a set of replacement coil packs and keep the old ones as spares. Yeah pretty much anything that moves or has current flowing through them have a service/life span interval.
 
Cool. Please post your experience of Before/After once you get 'em in and drive it. How many miles/km on yours?

Cheers.
 
Coil pack and igniter replacement intervals aren't something that's really talked about around here. Most people don't do anything until they fail. Sure, they last a long time, but how much of the 200K+ miles are they working optimally? If you want to measure the coil packs to see if they are in spec, here are the values:

Primary resistance: 0.67 - 1.05 Ohms
Secondary resistance: 9.3 - 16K Ohms

2 of mine measured in spec and one didn't. I replaced all 3 since they are all the same age. I got way better performance as a result.
 
in a bind a while back I went with Oreilleys also, lasted a year and crapped out.
Then I went and got all 3 denso from rock auto, cheaper and on 3rd year now.
the other day I looked them up for my tundra, denso is only 51. Then I checked current price for t4r and 53.
they also had some as low as 17 bucks. must be great quality.
who knows how cheap orielleys is getting them for and reselling. for the few dollar price difference Id stick with denso.

lifetime warranties are a gimmick...they dont expect you to keep a rig long.....forget avg time a person keeps car in us..and if it craps out under warranty...its your labor. I worked as a auto parts manager at one stage in my life. we could warranty exchange something out, sometimes twice, and still make a profit on original sale.
 
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3bears said:
in a bind a while back I went with Oreilleys also, lasted a year and crapped out.
Then I went and got all 3 denso from rock auto, cheaper and on 3rd year now.
the other day I looked them up for my tundra, denso is only 51. Then I checked current price for t4r and 53.
they also had some as low as 17 bucks. must be great quality.
who knows how cheap orielleys is getting them for and reselling. for the few dollar price difference Id stick with denso.

lifetime warranties are a gimmick...they dont expect you to keep a rig long.....forget avg time a person keeps car in us..and if it craps out under warranty...its your labor. I worked as a auto parts manager at one stage in my life. we could warranty exchange something out, sometimes twice, and still make a profit on original sale.
Click to expand...

If they fail in a year, I will come back to this thread so you can say "I told you so." :D
 
These coils always interesting topic.
I can kind of see the possibility of performance gains, hot coils can do funky stuff.
When I had spark issues and purchased a coil that didn't fix it saved for later. I have new base line numbers from it.
I do a cold to hot test on used ones using a toaster oven extended leads to my meter outside oven
for extended times mimic a drive monitored resistance. In spec call it good problems found elsewhere.
Having 1 new Denso 2 more may find their way here since 01 at 233K next plug n wire change. For the *ell of it.
 
Zhehan said:
Most people don't do anything until they fail. Sure, they last a long time, but how much of the 200K+ miles are they working optimally?
Click to expand...
Here I am with 325k on my original coils and things still seem to be good (lifted/armored and still get 18-19mpg). I did finally replace the wires and boots for the second or third time recently.

-Charlie
 
I have a feeling that a lot of us end up with new coil packs, plugs, and wires while trying to find an easier solution to replacing the injectors - happened to me (3 Densos) :) I did notice she was running very well and felt spunkier. I also grabbed an igniter at the junkyard for a spare. Someone here said igniters rarely fail and I often see them still there on otherwise well-picked over yard runners.....
 
I replaced the cats with some hilariously expensive Magnaflow carb ones and new sensors.... wow what a difference. The cats the were there were some craptastic cheapies. Even the pipes were too small.

Well that solved her shibox status. Check lights gone.

Wires and plugs were good in mine. Only 4-5k miles on them. OE plugs, after market wires.

So I thought who knew what difference that would make.... so what the hell, rolled in a new set of OE coils, wires and plugs. Dang..... ran even better..... so what the hell, let's do the igniter too......

It's actually not that slow anymore...lol. Should have done this a while ago. She used to be anemic and slow with ECT being almost mandatory. Not she gets up and scoots. Nothing like the twin turbo tundra, but it doesn't feel handicapped at least. Simply a joy to drive now.

Don't be scared to change some old parts. I couldn't have been more surprised in how different it drives now. Down shifts fasts, and super zippy around town now.
 
Right on, Romeo1. That sounds great!

Edit: I should add that when my igniter failed in March, after replacing it, the truck fired up instantly. I also noticed that when shutting it down, it turned off instantly as well. Before the failure and resulting replacement of the igniter, when turning off the truck, it wouldn't shut down so suddenly. I didn't really notice it that much until after replacing the igniter. And, of course, it definitely ran better as well. It wasn't until the coil pack replacement that a real performance gain was noticed.

Stuff wears out. These coil packs do not have an infinite lifespan.
 
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I changed mine just due to preventative maintenance (also there was a crazy sale on them at the dealership) but didn't notice any difference...
 
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