[RedlineF30]

Originally Posted by 5w20

I’ve had a set of the NGKs give me trouble right out of the box and they showed zero signs of damage to the box or the plug themselves. Anything can happen.

Very true, the NGKs you used were the 97506? I checked the gap on mine because I wanted to aim for around .022 and noticed that 2 of them didn't seem to have the factory gap so I guess it's always a good idea to check.

[5w20]

Originally Posted by RedlineF30

Very true, the NGKs you used were the 97506? I checked the gap on mine because I wanted to aim for around .022 and noticed that 2 of them didn't seem to have the factory gap so I guess it's always a good idea to check.

Yes, NGK 97506. I bought them from a local autoparts (O'reilly) and didn't have an issue. I subsequently replaced 4 sets within the warranty period (1yr) because after about 10k miles because they tend to cause slight misfires. The first two lasted their normal mileage, while the 3rd set caused bad misfires after initial installation. I put in the previous set and it went back to the normal slight misfire under load. I always verify gap before installing, but I don't adjust it being as I haven't had any issue installing them with the preset gap. I usually try to purchase from reputable sellers to avoid the replicas. The car currently has a set from FCPEuro now.

[Orion4]

Originally Posted by LA1Z24

So the Bosch plugs were the culprit...Like I suggested and was quickly told no.

I dont believe any of us said "no". Just in our personal experiences, we had not suffered that issue with Bosch plugs. Regardless, glad it is resolved.

[Pussiwillow]

I also never said no, I removed Bosch from the car, there were no issues, I did it because I didn't know when they were changed, I replaced with updated Bosch and have been perfectly fine. I'm sure people experience issues with particular things when on large scale; maybe I'm lucky, either way, they work for me.

[kickthecan]

Originally Posted by LA1Z24

So the Bosch plugs were the culprit...Like I suggested and was quickly told no.

Again, anecdotal or else every BMW needs to be sent back in to change their plugs or the forum will be filled with threads about It

I don't see it


Same can be said about NGK.

[XutvJet]

Over 30 years of working on cars, it's been my personnel experience that Asian plugs work great in Asian and Domestic motors and German plugs work great in German motors. Much of what I've experienced seems to hold true with what I've read on the various forums I'm on. Why this is, I have not a clue, but I do know that NGK and Bosch plugs that you can get at many auto parts stores tend to have more issues than true OEM plugs.

Late last year I replaced my OEM Bosch plugs that were nearly 5 years old/45K miles with another set of OEM Bosch stock gap plugs. No issues at all to report and the car has a Dinan Stage II piggyback, catted DP, CP, MPPK airbox, Wagner EVO Comp 1 IC, and MPE (~370whp/390wtq).

[harkes]

Strange with those plugs... Ran both OE Bosch and currently NGK. All at factory gap and zero issues. Factory OE are good for maxing out the PS2 on methanol also.