I knew our coils sucked but didn't expect to run into problems with so little mods. Anyway, car ran fine on a 95 degree day but this morning it was 59 degrees and the car didn't like it.

My question is... should I just buy the 997 coils or pony up the coin for the BBi's?

 

With the 997's you should be fine. They are good up to big hp but they just crack over time. New plugs?

 

our coils don't "suck" they are just maintenance related items that along with plugs would/should be changed with any new tune as a matter of preventative maint.

according to a recent thread, the plasma coils that were once available from bbi and no longer are, are now north of a grand.. maybe even 1200?!

that would buy me 6 sets of oem 997 coils.

 

Thanks for the info. Where is the best place to buy 997 coils?

 

any of the online cheap vendors. ecs/pelican/suncoat et al. i think 40 ea for beru is about best price http://www.pelicanparts.com/catalog/..._pg1.htm#item2

says o/s but thats gotta be very temporary ( if even true )

 

i'd check and regap plugs first. Start with the basic stuff.

 

That behavior is a sign the coils are bad. My Turbo misfires once in a while when the temperature drops and humidity goes up for instance when we get some monsoonal moisture. (No rain though, but that is supposed to come later in the year. El Nino. Yeah baby! Getting ready: New top on the Boxster -- the old one leaks; New rear tires too. The ones on the car now are nearly to the wear bars.)

I just checked with the SM today and my Turbo's plugs were replaced last August about 12K miles ago so I seriously doubt the plugs are at fault. Oh stock Turbo with no track time. (Nearly 5K of those miles were put on with a trip back east last Dec. then the drive back home in early Jan.)

I'm not a big fan of removing plugs and gapping them then putting them back.

To minimize possible wear and tear on the head threads I prefer to if the plugs have to be removed to just replace them with new ones. Correctly gapped of course.

 

plugs and coils is a must on most of these cars with a tune...

 

+1, stock ignition system is quite good IMO, but need to ensure its up to date...all about basic P.M.

 

whats the difference between new threads and old threads on plugs in regards to the head threads? if installed properly and torqued properly what would the thread have to worry about on older plugs?

 

Listen, I love you guys but I have to disagree. I've been modding cars for a long time and have never needed to change coils as part of routine maintenance or after a tune. Plugs yes, coils no.If that is a reality with this car than the ignition system does suck.

 

I have a crack on one of my original coils. 105000 miles. I even see some rust on it. Still runs perfect. Seems alot of people like to buy new stuff just for the hell of it. I don't get it.

 

I don't think it's just for the hell of it. When replacing plugs at let's say 90 or 120k service interval. The amount of work required to swap out the plugs, might as well replace the coils too.

 

i would defer to your expertise, and i only really know what i know from "these" cars. since chipped 335i's dont count

but when i posted as part of "preventative maintenance" coils should be swapped? it's really just "due" diligence" esp when swapping out other parts, and i meant just that. just that is part of maintenance anyway, and even porsche suggests plugs every "major" svc which is at 30k increments so coils should be changed as a matter of course when mods occur ( esp engine mods ) so that (a) a baseline for the new parts is established and (b) commensurate with that, those parts can be ( usually/hopefully?! ) be eliminated as the cause of niggling little issues post upgrade(s), such as you're having.

plugs and coils ( at least in THESE cars and ESPECIALLY if tuned?? ) ARE part of "regular" maintenance and especially plugs as tuned turbos eat them! check out the 90k service regimen. that said, you're certainly right, plugs could easily be a 4x1 ratio against coils, but the rule for me, for a $40 part ( well, times 6 lol ) is if i dont know when they WERE last swapped? out w the old, in with the new. it's just *smart* ownership, and the more mods ya have? the smarter the practice becomes. ymmv.

 

New plugs have a dry thread coating/treatment that acts as a lube, but it is a one time thing.

Removing the used plug then re-installing it and torquing it can increase the wear and tear on the head threads.

Using some thread lube is not a suitable substitute for the new plug thread coating/treatment. Besides possibly affecting heat transfer from the plug to the head the lube can provide a gap through which combustion gases are forced which can increase the corrosion rate at the plug thread and head thread interface. And the wrong thread lube can damage O2 sensors.