WTF is up with my spark plugs?!?!?

TURBevO8 · Post by **TURBevO8** » September 22, 2007

Changing spark plugs. Should be as simple as changing a tire right? Maybe even easier? Well as far as physically changing them I will agree but listen to this shit. (Sorry, I am a bit frustrated here).

Swapped my plugs out for some NGK BPR7ES plugs the other night. Gapped them to 0.026" as that is recommended for 23+ psi boost. Previously I had NGK BR7ES (the "P" just stands for protruded tip). Anyway, the car ran fine at throttle but the idle is all fucked up. It dropped from 1100 RPM to 500 RPM. So I thought the gap was too tight to make a nice enough spark with my low amperage ignition so I took them out and gapped them 0.029". Still the same problem. Put the old crusty BR7ES plugs back in and the idle returned to normal. So then I went and bought new BR7ES plugs and dropped those in today. Check the gap and just like the old plugs, the gap from NGK is about 0.028". Took the car for a ride and the idle is still just as messed up as with the BPRs!!!! Now that makes sense to me as the P shouldnt matter. What does NOT make sense is my old BRs work perfect and my new BRs dont! It makes no fn sense at all!!!! They are identical plugs!!!

So what do you guys think? I DO have a custom tune but that shouldnt matter I dont think. I mean you shouldnt need a new flash every time you change plugs! lol! I am really confused here. Could my old plugs be a "magic" set of plugs??? Man am I frustrated! And I am to go back on the dyno here in like 2 hours! Ahhh!!!!

Post by **Zero** » September 22, 2007

or the car is just used to the old plugs and the new ones prvide more spark which is causeing the tune to be out of whack because it is a custom tune... from what i understand when you get your car tuned everything from fuel to spark is adjusted for the best results and if your now getting more spark then its used to then the car is going to react to that...

TURBevO8 · Post by **TURBevO8** » September 23, 2007

the only thing that is adjusted during a custom tune is AFR and ignition timing. And in my case I had them up the idle back to stock as my cams dropped the idle to like 700 RPM because of the increased vacuum.

But at any rate I drove the car down to DC yesterday for a BBQ/meet at AMS (Atlantic Motorsports) and now the car idles fine. Maybe the new plugs just needed broken in. I dont know. At any rate the car seems fine now.

munster · Post by **munster** » September 23, 2007

They might have just needed a few cycles on em. My dirt bike does that all of the time when I put a new plug in.

TURBevO8 · Post by **TURBevO8** » September 23, 2007

^^Yeah I think you are right. Never experienced that or heard of that before but seems to be my situation. Maybe the fact I run coppers?

munster · Post by **munster** » September 23, 2007

I run standard plugs in my car. It's been through a few sets, and I have a little high of an idle for a little while then it mellows out.

I think all of the other plugs are gimmicks anyhow. More $ and foul out just as fast.

boostjunkie95 · Post by **boostjunkie95** » September 23, 2007

Same thing happened to me. The new plugs just need ran a little bit to get them burnt in. You'll be fine.

tommybanzai · Post by **tommybanzai** » September 24, 2007

rub them across your nuts a few times

that always works

Post by **Nikku** » September 25, 2007

ignition timing does have something to do with spark...:X. toy with it.

T0DA · Post by **T0DA** » January 06, 2008

munster wrote: I think all of the other plugs are gimmicks anyhow. More $ and foul out just as fast.

Yes.