spark plug ?'s
Grand Champion
Joined: Nov 2004
Posts: 6,099
Likes: 6
From: Colorado
Yes you need to gap them. Plugs may come pre-gapped, but that doesn't mean they are gapped correctly for your vehicle (plugs can fit more then one application). Always gap your plugs before you install. I have never bought plugs that had the correct gap for my truck.
Legend
Joined: May 2005
Posts: 8,663
Likes: 7
From: Central Oklahoma
Every fastener on a vehicle is torqued to a specific value, so even though you "never heard of torquing plugs" whenever learning vehicle repair does not mean it's unheard of.
Many years ago, I knew someone who worked part time for an auto parts store. He was assisting me in performing maintenance on one of my vehicles and he told me the plugs I bought were pre-gapped and I didn't have to gap them. I told him he was full of it but he was adamant and wouldn't back down. I checked the gap of every new plug and they were +/- 0.10-0.25 of what the vehicle specifications demanded. He wrinkled his face and then stated that the parts sales rep assured him *ALL* spark plugs came pre-gapped. I told him to tell the rep he doesn't know what he's talking about, because there are so many different applications for any one particular spark plug that it's impossible for them to be pre-gapped.
Always, always, always set the gap before installing any new spark plug.
Many years ago, I knew someone who worked part time for an auto parts store. He was assisting me in performing maintenance on one of my vehicles and he told me the plugs I bought were pre-gapped and I didn't have to gap them. I told him he was full of it but he was adamant and wouldn't back down. I checked the gap of every new plug and they were +/- 0.10-0.25 of what the vehicle specifications demanded. He wrinkled his face and then stated that the parts sales rep assured him *ALL* spark plugs came pre-gapped. I told him to tell the rep he doesn't know what he's talking about, because there are so many different applications for any one particular spark plug that it's impossible for them to be pre-gapped.
Always, always, always set the gap before installing any new spark plug.
Rookie
Joined: Apr 2011
Posts: 61
Likes: 0
From: Dallas, TX
Alright, went out today and bought some NGK g-power platinum spark plugs. 8 of them in fact. And the box for them says to torque down to 18-21 ft. lbs. for use with aluminum heads. When I bought my last set of bosch's, they said to torque them down also, which i did, but my buddy that's a mechanic, says they never torque spark plugs down. Just hand tight, plus 1/2 turn. Just wondering if I need to get my torque wrench out to do this, or is the "mechanics" method good enough. He thought I was crazy taking a torque wrench to my spark plugs, but hell, I just did what the box said to do.
Also, forgive my rookieness, but do I need to gap these spark plugs. That's another thing my mechanic friend asked me about the last set. No, I didn't gap them, or check the gap, or whatever, but why did I have to tell the parts store what kind of vehicle and engine it was, if I had to do the work to set them up properly. My bosch's seemed to do okay, but I recently fixed the plenum, and it was recommended to do a tune up, due to the rear plugs possibly fouling.
So atm, I have a new set of spark plug wires. BWD select (the more expensive ones at o'reillys 7mm) is the brand, which I would also appreciate if someone happens to know which length wires go to which cylinder would be awesome. Otherwise, guess I can just take each one off and replace with the same length wire, 1 by 1. And I have new spark plugs. I realize that dist. cap is also part of a tune-up, but the cap is only 1 year old. Should I replace it??
Also, forgive my rookieness, but do I need to gap these spark plugs. That's another thing my mechanic friend asked me about the last set. No, I didn't gap them, or check the gap, or whatever, but why did I have to tell the parts store what kind of vehicle and engine it was, if I had to do the work to set them up properly. My bosch's seemed to do okay, but I recently fixed the plenum, and it was recommended to do a tune up, due to the rear plugs possibly fouling.
So atm, I have a new set of spark plug wires. BWD select (the more expensive ones at o'reillys 7mm) is the brand, which I would also appreciate if someone happens to know which length wires go to which cylinder would be awesome. Otherwise, guess I can just take each one off and replace with the same length wire, 1 by 1. And I have new spark plugs. I realize that dist. cap is also part of a tune-up, but the cap is only 1 year old. Should I replace it??
ALWAYS CHECK THE GAP
even pregapped spark plug, you'll get atleast one every now and again thats way off
like i just installed a set of spark plugs, only 1 was off.. at about.70
when my gap is .35 according to my instructions on my engine bay
