Diagnose my spark plugs - Page 2

blee · 02-21-2005, 10:59 PM

Quote:

Originally Posted by lip277

Those look pretty good (in the normal wear-and-tear mode) from what I've taken out of my cars... Non plats that is.

Not sure about the M20 engine, but IIRC plats are specifically not recommended fore the S14. Something about fouling them very quickly, but I can't remember the reasoning. The common advice was to use copper plugs, possibly a set colder if you're running something out of the ordinary.

rumatt · 02-21-2005, 11:02 PM

Yeah, I read a lot of folks saying the cheapies actually work the best.

lip277 · 02-22-2005, 12:23 AM

Quote:

Originally Posted by rumatt

Yeah, I read a lot of folks saying the cheapies actually work the best.

I don't know about 'cheapies'..... But I've always had great luck with NGK's as opposed to Bosch. Personal preference I suppose. In 1986 or so when I rebuilt the M10 in the 2002, my mechanic/friend turned me onto NGK. Nothing against Bosch. Just a fan of NGK.

It's kind of funny actually..... I used the same plug in the 420SEL, 2002 and my John Deere mower for a while.

Makes it simple to go shopping. Cheaper by the dozen as well... OK - Maybe not.

I've actually gone to a cooler heat range on the 2002 but the Mercedes and the Kawasaki (in the Deere) still are plug-mates with the 2002 a close cousin.

Jason C · 02-22-2005, 03:55 AM

I heard that the rule is Bosch for Euro cars and NGK for anything from Asia. But I suppose it's not a hard and fast rule.

blee · 02-22-2005, 10:44 AM

My M3 ran great on the Bosch plugs, but I've heard different people recommend NGKs or Bosches over the other for various reasons. I think it ends up being personal preference or some random characteristic of one particular engine that makes it more suitable for a certain plug. Probably not a ton of difference either way.

Eric Giles · 02-22-2005, 07:53 PM

Run ONLY the Bosch Supers that are for the M20B25 engine. Others have been tried over the years, but this engine was designed for these plugs and they work the best. And it is true, do not use Platinum plugs on these engines either-it will eventually run like crap!

Just buy the Bosch and change them at the recommended 15k miles you will have no problems.

02-22-2005, 07:53 PM	#16
Eric Giles Suffering from BMWitis... Join Date: Oct 2003 Carmudgeonly Ride: '00 M5,'88 M3,'87 325 Location: Waynesboro, MS Posts: 41	Run ONLY the Bosch Supers that are for the M20B25 engine. Others have been tried over the years, but this engine was designed for these plugs and they work the best. And it is true, do not use Platinum plugs on these engines either-it will eventually run like crap! Just buy the Bosch and change them at the recommended 15k miles you will have no problems. __________________ Eric Giles '88 M3 Diamantschwarz/Black '00 M5 Lemans Blue/Black '87 325is Delphin/Black

02-21-2005, 11:02 PM	#12
rumatt Mugwump Join Date: Oct 2003 Carmudgeonly Ride: E46 330i, Chevy Colorado, Tesla Model 3 Location: NY Posts: 17,475	Yeah, I read a lot of folks saying the cheapies actually work the best.

02-22-2005, 03:55 AM	#14
Jason C Carmudgeon Join Date: Jul 2004 Carmudgeonly Ride: Invalid Carriage Location: Bay Area, CA Posts: 1,932	I heard that the rule is Bosch for Euro cars and NGK for anything from Asia. But I suppose it's not a hard and fast rule.

02-22-2005, 10:44 AM	#15
blee Doctor Mudgeon Join Date: Oct 2003 Posts: 6,433	My M3 ran great on the Bosch plugs, but I've heard different people recommend NGKs or Bosches over the other for various reasons. I think it ends up being personal preference or some random characteristic of one particular engine that makes it more suitable for a certain plug. Probably not a ton of difference either way.