Spark plugs - United Bimmer Community

**Dudesky** · 01-05-2006, 05:43 AM

About to change out my spark plugs for the first time (Bosch OE dual electrode). And I got to thinking which train of thought is correct: Will the new ones tax my electrical system more because they're newer, or are the old ones taxing it more right now because they're old and inefficient? I'm expecting some sort of change since my car is up there in mileage.

**c1apton** · 01-05-2006, 06:05 AM

Your old plugs are taxing your ignition system because of resistance rises as they wear. After putting in new plugs although they won't be "taxing" your ignition, the addition might amplify any (if any) existing problems. I think you'll notice faster starts, quicker response and better mileage

**Dudesky** · 01-05-2006, 08:01 AM

Makes sense. Yea, I'm expecting the dreaded 'problem amplification', or the old 'fixing one thing breaks another thing' syndrome

**c1apton** · 01-05-2006, 08:08 AM

Make sure you do the plug change when engine is cold and the plugs have a dab of anti seize compound on the threads.

**Dudesky** · 01-05-2006, 10:51 AM

Yea, when cold, I knew that part. But the anti-seize thing . . Some say don't use it as it interferes with the ignition current flow. Thoughts anyone?

**c1apton** · 01-05-2006, 12:34 PM

That's why I mentioned a "dab". Alot of plugs these days come pre coated but just a small dab just to keep threads from seizing.

**kestrel325is** · 01-05-2006, 02:53 PM

I've always put a small amount of motor oil on the threads before inserting the plug. Holdover from what my Dad taught me when I was younger.

**billycuth** · 01-05-2006, 03:37 PM

what does changing them when they are hot do?

**Dudesky** · 01-05-2006, 03:59 PM

Quote:

Originally Posted by billycuth

what does changing them when they are hot do?

The plugs are prone to gumming up when hot. More importantly, you'll have a harder time getting them off when the engine is warmer, risking cracking or cross threading.

**c1apton** · 01-05-2006, 04:42 PM

also when engine is hot & you pull plugs the actual plug holes can distort.

**billycuth** · 01-06-2006, 07:51 AM

thanks guys. good info. never heard that.

**jms** · 01-06-2006, 08:37 AM

I've heard not to use platinium, only use copper but I've also heard plats are fine. Anyone have any idea who's right?

dudesky which are you putting in, and more importantly what did you take out?

**c1apton** · 01-06-2006, 08:42 AM

I use the platinum 4s (they came with car from factory) From what I've heard coppers work fine, just don't last as long. That's the only negs I've ever heard that were credible.

**billycuth** · 01-06-2006, 09:20 AM

I did platinum +4s a little while back... caused misfire problems and I immediately cracked a couple of them within a week. BMW shop told me not to use platinums as the 328i (e36) doesnt create enough spark to warrant their use. OEM copper is the way to go, I am told.

**c1apton** · 01-06-2006, 09:25 AM

Yea again it's what the car is designed for. Mine came factory with the 4s and they work great. Friends who have tried to save a $ went with coppers only to have them last like 15k before noticing mileage drop and lags. But I've heard the similar to what you said, sometimes upgrading isn't feasible (mostly hype from plug mfgrs)