Z4M spark plug replacement interval

[KevinM]

I don't drive the M coupe that much so this many years later it has just rolled over 30K miles. I did the valve adjustment and changed all the fluids. Does anyone have an opinion on when to change the spark plugs? I know it is done with the "official" Inspection II, which usually is around 60K. Mike Miller doesn't provide any S54 specific advice in his handbook. Is it a waste of money to replace them now? Car is not tracked.

Thanks in advance.

[XMetal]

I had replaced them during each of my valve adjustments simply because they're getting taking out during that time anyway. I just had my inspection II (2nd valve adjustments) done at 45K miles, so the car is on it's 3rd set of spark plugs. It's an overkill, I know; but the extra $50 spent on spark plugs gives me a tiny peace of mind and hopefully will somewhat prevent those pesky coil packs from premature failures.

[coh661]

You could always pull them out and inspect them yourselves and decide. The condition of the plugs will probably depend on a lot of factors. I'm no mechanic but did mine myself at 50k miles. Really simple and can be done with basic tools and a torque wrench.

[KevinM]

Originally Posted by XMetal

I had replaced them during each of my valve adjustments simply because they're getting taking out during that time anyway. I just had my inspection II (2nd valve adjustments) done at 45K miles, so the car is on it's 3rd set of spark plugs. It's an overkill, I know; but the extra $50 spent on spark plugs gives me a tiny peace of mind and hopefully will somewhat prevent those pesky coil packs from premature failures.

Originally Posted by milamookie

You could always pull them out and inspect them yourselves and decide. The condition of the plugs will probably depend on a lot of factors. I'm no mechanic but did mine myself at 50k miles. Really simple and can be done with basic tools and a torque wrench.

Thanks! Yes, I guess if I am thinking about it, I might as well just change them.

[StickMon]

I replace them at each valve adjustment, since I have to take them out anyways and they use crush washer seals.
I've also switch to the iridiums, which last even longer, and you can get them cheap on Amazon.

[DBZ4]

2013 Z4 e89 47,000 miles. When accelerating hard from 0mph (pedal to floor) I get a misfire around 60mph and the car goes into slow mode. Code reader shows a misfire. I'm thinking that I should start by replacing the spark plugs. If that doesn't take care of it, replace coil packs next?

First post here. Thanks for your help
dbz4

[Terraphantm]

Originally Posted by XMetal

I had replaced them during each of my valve adjustments simply because they're getting taking out during that time anyway. I just had my inspection II (2nd valve adjustments) done at 45K miles, so the car is on it's 3rd set of spark plugs. It's an overkill, I know; but the extra $50 spent on spark plugs gives me a tiny peace of mind and hopefully will somewhat prevent those pesky coil packs from premature failures.

Why are you taking out the spark plugs for valve adjustments?

[Terraphantm]

Originally Posted by StickMon

I replace them at each valve adjustment, since I have to take them out anyways and they use crush washer seals.
I've also switch to the iridiums, which last even longer, and you can get them cheap on Amazon.

They actually don't unless you're talking about racing plugs. Non-OE and non-racing Iridium plugs still have nickel grounds, so they still wear fairly quickly.

[SD ///M4]

Originally Posted by Terraphantm

Why are you taking out the spark plugs for valve adjustments?

I wondered that myself. When I bought my 2006 M Roadster in 2012 at ~32,000 miles, the Inspection I hadn't been done so I did it myself, with the help of a friend with an E46 M3 who had a shim kit. I don't recall removing any spark plugs, particularly because if I had I would have had six more holes to block with shop towels.

[XMetal]

Originally Posted by Terraphantm

Why are you taking out the spark plugs for valve adjustments?

Removing the spark plugs makes it easier to rotate the crankshaft as you move through the cylinders (no compression).

[Terraphantm]

Originally Posted by XMetal

Removing the spark plugs makes it easier to rotate the crankshaft as you move through the cylinders (no compression).

It's not particularly hard with them in though.

[johno8888]

I had my inspection one done at 30000 miles in the dealer said that I did not need a valve adjustment. I looked in the manual and could not find the requirements for the interval. I see some evidence that this is really needed until 60,000 miles.

I never track my car and rarely drive it hard.

How do I know when I need a valve adjustment?

[Shipkiller]

Your dealer is wrong about not needing a valve adjustment. He has no way to tell.

You have to go through the process of measuring each valve shim (clearance) to determine if you need to replace/substitute for a new shim.

The dealer can say no valve shims needed changed after doing the 'valve adjustment', but you have to go through the process.

[gds52]

Originally Posted by Shipkiller

Your dealer is wrong about not needing a valve adjustment. He has no way to tell.

You have to go through the process of measuring each valve shim (clearance) to determine if you need to replace/substitute for a new shim.

The dealer can say no valve shims needed changed after doing the 'valve adjustment', but you have to go through the process.

This is debatable.
My bmw mechanic friend (dealership 25+ years exp) told me by hearing the engine sound that I don't need it.
I also have a local Bmw shop with very experienced owner/mechanic...he told hearing the engine sound at 30k miles that I don't need it.
I tracked my car for few times and it's been good.
Now I will get it checked at 40k miles oil change in spring.

[Terraphantm]

Originally Posted by gds52

This is debatable.
My bmw mechanic friend (dealership 25+ years exp) told me by hearing the engine sound that I don't need it.
I also have a local Bmw shop with very experienced owner/mechanic...he told hearing the engine sound at 30k miles that I don't need it.
I tracked my car for few times and it's been good.
Now I will get it checked at 40k miles oil change in spring.

It's only audible if they're grossly out. Tracking the car a few times is meaningless.

Best is to just get a set of feeler gauges and check yourself.

[gds52]

Originally Posted by Terraphantm

It's only audible if they're grossly out. Tracking the car a few times is meaningless.

Best is to just get a set of feeler gauges and check yourself.

Is it easily doable? I mean not much to remove to check with gauges. I can try to do it myself.
Thanks

[XMetal]

Originally Posted by gds52

Is it easily doable? I mean not much to remove to check with gauges. I can try to do it myself.
Thanks

It's doable, but not necessarily easy. It's tedious. There are lots of youtube videos. Just search for "S54 valve adjustments"

[Terraphantm]

Originally Posted by gds52

Is it easily doable? I mean not much to remove to check with gauges. I can try to do it myself.
Thanks

It's a little tedious, but not technically difficult IMO. I've done the last 100k miles' worth of valve adjusments on my car and never found the job to be particularly difficult. Changing the 6th cylinder exhaust shims can be a bit annoying, but I don't think that's as bad on the Z4M vs the E46 M3.