Spark plug gaps

msm15 · Post by **msm15** » 16 Nov 2008, 18:21

So I was in the process of doing a tune up on my 98 s70 glt and got stuck by the spark plugs, the screws holding down the plastic cover were stripped beyond help and the first attempt to extract them with an extractor bit failed. Which probably meant the previous owner hadn't changed them in a while and the car has 224k now.

I finally got the cover off and removed the plugs and checked the gap they were soo past there limit they measured in at .053+ GEEEEE so that would explain my sluggish cold starts in the mornings I had almost no power until the car warmed up.

I replaced them with bosch premium plus plugs but from what people said here the proper gap should be around .028 The new ones were all the same at .02 is that going to be a problem ?

thanks

Post by **MadeInJapan** » 16 Nov 2008, 18:48

When you say "premium," do you mean Platinum? If so, don't use those (many have had problems with them), get some regular Bosch copper plugs (cheap...less than $2 each)...if the gap is at .02, you'll need to get a gap tool (cheap- usually $.99 at the counter) to spread it to .028 inches (not mm). If you have a tuned car or a turbo, I recommend down to .026. The gap you speak of, at .02 is the same as .020 which is .006~.008 too little. It could make a difference. Our Volvo's are very finicky when it comes to plug gaps.

msm15 · Post by **msm15** » 16 Nov 2008, 19:06

woops yeah I meant platinum, ok I will swap them out, I just wanted to see if these make a difference. thanks MIJ

In terms of re gapping I have the tool can I just force the the metal out ?

Post by **MadeInJapan** » 16 Nov 2008, 20:42

Yes, that's how it's done...if you get the gap too far, push it against a hard surface (like concrete floor) to push it back in..do this until you get it right.

msm15 · Post by **msm15** » 16 Nov 2008, 22:41

will do, thanks for the help MIJ greatly appreciated

Mike-Halewai · Post by **Mike-Halewai** » 17 Nov 2008, 12:17

I'm running NGK Platnums and NGK plug wires, no problems at all.

Post by **MadeInJapan** » 17 Nov 2008, 15:28

That's good to know...mostly I've heard plat's (bosch) and wires (bosch) are not good in our cars- don't know much about other plugs or wires.

sony2000 · Post by **sony2000** » 19 Nov 2008, 17:21

The parts pro at my Volvo dealership said to me last week, that Volvo plugs are made to cover a wide temperature range, where as, the range on Bosch, is much narrower.

nathan chase · Post by **nathan chase** » 10 May 2010, 01:29

My gap tool only goes to .040" to I used a credit card as they are 0.030" thick. Pretty close to the 0.028" spect for these car. For those of you who don't have the right tool

Post by **polskamafia mjl** » 10 May 2010, 01:38

ehh...not sure .03 is good enough. The gapping tools are dirt cheap. Try to get one and set your gap to .028"... .026" for those with high boost on their Turbo bricks.