Spark Plug Change

[Mpowah]

Hey folks -

When would you consider changing your spark plugs? To refine my question further, I am not asking when does the manufacturer recommend it but rather when is it reasonable to change it? I have 46,000 miles on my 08 M3 and I baby the car in the event this impacts the responses to this question. Thanks for your input in advance!

[elm3]

Originally Posted by Mpowah

Hey folks -

When would you consider changing your spark plugs? To refine my question further, I am not asking when does the manufacturer recommend it but rather when is it reasonable to change it? I have 46,000 miles on my 08 M3 and I baby the car in the event this impacts the responses to this question. Thanks for your input in advance!

If they haven't changed it by now, I would do it. Just my 0.02cents.

[Mpowah]

Thank you for providing your input. I'm looking to do it at 50,000 miles.

[baba louey]

I know that plugs last a lot longer than they used to but 4 years and 46K miles seems a tad long. Change them.

[MA///M3]

I would change them now too. Bay it or not. I have a 08, changed around 35K.

[e1000]

Change them. Be prepared for your car to feel like a monster for about a week. It's great.

[MDyDinanM]

I change mine every 30K miles.

I follow Mike Miller's Old School Maintenance Guide.

See attached

[M4Now!]

Pretty sure the dealer changed mine at 30k - which seemed really early, but for it to be included in the scheduled maintenance (so BMW pays), apparently it's needed. Maybe the S65 is really sensitive to gap?

Cheers

[Mpowah]

Good information sounds like I better get it done!

[gatorfast]

If your plugs have never been changed I would do it immediately and switch dealer's as this should have been done at 37k miles (per manufacturer recommendation).

However, seems like most people have them changed by the dealer before the car hits 37k, usually somewhere in the low 30k range. Think my car had it done around 32k miles and I will be doing it again shortly when I hit 60k miles.

On a side note, quit babying the car an drive it hard! Whats the point of owing an M3 if you drive it like a grandma?

[elm3]

Originally Posted by mdyaman

I change mine every 30K miles.

I follow Mike Miller's Old School Maintenance Guide.

^^^^ +1, if you are planning on keeping your car for a long while, I would do the old school maintenance schedule for our cars.

[MDyDinanM]

Originally Posted by gatorfast

.

On a side note, quit babying the car an drive it hard! Whats the point of owing an M3 if you drive it like a grandma?

you know, I hear this all the time... "quit babying your car - drive it hard". The reality is that with the roads, traffic, and cops in my area, its quite impossible to drive your car hard.

[gatorfast]

Originally Posted by mdyaman

you know, I hear this all the time... "quit babying your car - drive it hard". The reality is that with the roads, traffic, and cops in my area, its quite impossible to drive your car hard.

I know what you mean. Im a victim of rush hour and heavy traffic too here in south florida. But any chance I get (even though its not many) Im definitely flooring it to redline

[Lorde]

Originally Posted by Mpowah

Hey folks -

When would you consider changing your spark plugs? To refine my question further, I am not asking when does the manufacturer recommend it but rather when is it reasonable to change it? I have 46,000 miles on my 08 M3 and I baby the car in the event this impacts the responses to this question. Thanks for your input in advance!

Your owners manual says every 37k miles.

[thekurgan]

Originally Posted by Snig

Your owners manual says every 37k miles.

+1, I do it at 20-25k.

[shendrick]

Last time my car was in @ 28K miles, the SA said that the car was calling for spark plugs - so I said sure put them in because its like $500 if I went beyond the warranty which was just about up. It did make a difference in performance. What's odd is that you could rack up so many miles without your SA saying something.

[Mpowah]

Yeah I recall my SA saying something a few months back but I think I was in a rush and said ill get it done later. Sounds like later should be now lol

[thekurgan]

It's an easy DIY, plugs in this engine are also the knock sensors IIRC.

[kscarrol]

Originally Posted by shendrick

Last time my car was in @ 28K miles, the SA said that the car was calling for spark plugs - so I said sure put them in because its like $500 if I went beyond the warranty which was just about up. It did make a difference in performance. What's odd is that you could rack up so many miles without your SA saying something.

^ This! My car just popped up with the service indicator so I stopped by my dealer to make an appointment. Thought there might be a slim chance of getting it done while I waited because at 22+k miles I assumed it was simply an oil change. SA told me it was more than that and included changing the spark plugs.

[gimmethemuumuu]

As others have mentioned, owner's manual says every 37K miles. Most dealers do it at around 30K. Personally, I plan to do it every 25 or 30K miles, on the regular

[VCMpower]

Change them. Those plugs go through a lot with high compression and being used as combustion sensors by the coils.

Originally Posted by Mpowah

Good information sounds like I better get it done!

[Munit]

They are not "used" as combustion sensors, rather they simply sense what they normally sense and are relayed back to the coils which have the technology and sensing ability. The plugs are just like any old plugs.

The reason they are important is because if they have carbon built up or residue than the values can be off and thus cannot properly manage knock and timing targets. It ends up cutting a lot of timing with old plugs given it masks the signal