(Answered) 2009 with orig coils at 125k mls, would I notice a difference......

[m3peat]

If I put new ones in even though I have no codes/warnings saying they are bad?

I’m going to be putting in new plugs anyways and I get low rpm light pinging so thought I just put in new coils at this mileage and save the old ones.

Should I bother? Anyone put new coils in even though no codes thrown and notice a difference?

Ps plugs are at 31k mls and I have the Alpine tune, stg 1, no other mods. I always use some top tier premium gas here in SoCal.

Thanks in advance

Update: well, I can say with virtual certainty that the additional smoothness and barely noticeable extra pep in my cars step is not due to new coils.

I would attribute those things to fresh oil, new plugs and air filter done at the same time as the new coils.

I now have 8 working backup coils if one of the new ones fails.

[m3peat]

Bump
Anyone put in new coils without getting warning codes?

[GORDON.M3]

Yes, you would notice a difference. I would consider these as preventative maintenance items. Plugs every 20k, and coils every 60k.

[chocstraw]

I haven't noticed improvements when replacing them in the past, but 125k is a lot. If you don't want to shell out the...$800? to get them all replaced, I'd recommend buying a code reader and a single replacement coil in case one decides to go bad in the middle of nowhere. The vibrations from a bad coil and imbalanced motor are very violent and usually require a tow.

[doogee]

I'm on all original coils at 213,000 KM (132K Miles)

I'd be surprised if yours were bad. They're very well made.

[m3peat]

Thanks for the responses

Originally Posted by doogee

I'm on all original coils at 213,000 KM (132K Miles)

I'd be surprised if yours were bad. They're very well made.

I’m not saying they are bad but do they ‘wear’ like other maintenance items and I could/would see a slight performance improvement?

I wouldn’t be expecting a world of difference either if there was an improvement but maybe these just perform at 100% or like sh!t. That’s why I’m asking, I don’t know.

[pbonsalb]

I think at 10 years and 100k plus miles, replacing the coils could help. They do lose power over time, which is most noticeable on forced induction cars that have greater combustion pressure — they get spark blowout and stumbling as the coils weaken and new coils typically fix the problem. For our naturally aspirated cars, this won’t happen as soon.

Most likely your issue is a widened gap on 31k mile plugs and/or 91 octane gas, but there is a chance the old coils could be contributing. One thing that makes me more concerned on these cars than other cars is the ionic knock sensing. I don’t know enough to say it is affected by increased resistance in aged coils, but it seems possible. I have thought about replacing mine, which are 11 years old and have 100k miles.

[Helmsman]

Originally Posted by GORDON.M3

Yes, you would notice a difference. I would consider these as preventative maintenance items. Plugs every 20k, and coils every 60k.

Hey Gordon, do you really notice any difference when replacing plugs at 20k miles, or do they come out bad?
Replaced mine first round at around 19k, looked fine, felt no diff. At 43k now and starting to think, should I really...

[GORDON.M3]

Originally Posted by Helmsman

Hey Gordon, do you really notice any difference when replacing plugs at 20k miles, or do they come out bad?
Replaced mine first round at around 19k, looked fine, felt no diff. At 43k now and starting to think, should I really...

The adaptations on the ECU do. The butt dyno not so much. SYT_Shadow also recommends earlier spark plug intervals for the M3.

There is a reason behind why even BMW recommends shorter spark plug intervals when they sell the BMW Performance pack tune on the N54/N55 engines. Even when I did my plug service on my old 135i... just by looking at the plugs they looked like they could do another 20-30k but for peace of mind and for the greater health of the engine I replaced them earlier/according to the BMW PPK recommendations.

[SYT_Shadow]

Originally Posted by GORDON.M3

The adaptations on the ECU do. The butt dyno not so much. SYT_Shadow also recommends earlier spark plug intervals for the M3.

There is a reason behind why even BMW recommends shorter spark plug intervals when they sell the BMW Performance pack tune on the N54/N55 engines. Even when I did my plug service on my old 135i... just by looking at the plugs they looked like they could do another 20-30k but for peace of mind and for the greater health of the engine I replaced them earlier/according to the BMW PPK recommendations.

Someone once showed logs where after 10k miles the car was no longer hitting targets. That's why I change mine every 10 -15k

[wfdeacon88]

Someone a few months back on the whatsapp group for this board sent out a link where one could buy Bosch injectors direct from them for ~$300 or less. Can't remember how, but it was something that I remember was waaayyy cheaper. Anyone familiar with this? What's the cheapest place to get new ones?

[pbonsalb]

I paid $232 shipped for 8 Bosch 0986221059 injectors from FCPEuro a few months ago.

[Mvy]

I replaced mine when I saw very choppy dyno results after a SC install. It made a big difference in my case on smoothness. I never threw any codes. I agree with those that say you should replace them. I went with OEM from FCP euro and they have been good for me. https://www.fcpeuro.com/products/bmw...ch-12137841754

[Scrippy]

Originally Posted by GORDON.M3

Yes, you would notice a difference. I would consider these as preventative maintenance items. Plugs every 20k, and coils every 60k.

This is ridiculous. Super glad you have done this but not necessary my friend.

[Helmsman]

Originally Posted by SYT_Shadow

Someone once showed logs where after 10k miles the car was no longer hitting targets. That's why I change mine every 10 -15k

Cheers SYT. From what I understand you track your regularly which I assume ad further stress o the plugs?

[SYT_Shadow]

Originally Posted by Helmsman

Cheers SYT. From what I understand you track your regularly which I assume ad further stress o the plugs?

Yes, for sure. But i change every 10k miles on the street m3 as well, it's pretty cheap and after you've done it twice you're pretty fast in changes

[pbonsalb]

At 30k, the gap on my street driven plugs were visibly wider. The center electrode had worn into an oval shape. 10k change interval is probably not necessary, but something shorter than the factory 32k or 37k could help.

[Helmsman]

Thx guys, at 24k on current plugs so maybe I'll replace with next OC.

[Sandye90m3]

210,000 kms, and original coils. I do replace my plugs every 30k kms cause I can get them done for ~$400cad

[m3peat]

Updated initial post. Tltr: I don’t believe the new coils did anything but cost me a pretty penny. My original coils were working just fine. New plugs, oil and air filter made all the difference I could feel.

[tdott]

Originally Posted by m3peat

Updated initial post. Tltr: I don’t believe the new coils did anything but cost me a pretty penny. My original coils were working just fine. New plugs, oil and air filter made all the difference I could feel.

Even though they might have had no performance benefits, atleast you know they will probably be good for atleast another 100k now.

[8500RPM]

Originally Posted by m3peat

Updated initial post. Tltr: I don’t believe the new coils did anything but cost me a pretty penny. My original coils were working just fine. New plugs, oil and air filter made all the difference I could feel.

Sell your coils as working replacements and keep 1 or 2 for spares. That should help recoup the cost a bit.