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Spark Plug install??

21103 Views 35 Replies 22 Participants Last post by  GregKopp
Hi.

Been searching the forums for a while now and I can't seem to find any posts directly related to this. I'm mechanically inclined, but would like to make sure I do it right the first time.

Is there anyone out there who has done a spark plug change and documented the process? I have no clue as to how easy or difficult this process is.

Also, the recommended spark plug for the stock engine is a heat factor of 6. Is this correct?

Thanks for all your help guys.
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why are you changing it? how many miles do you have?
why are you changing it? how many miles do you have?
46k.
hmm well i cant find a guide (in celica forums) but all you do is take the coil pack off and spark plugs are down in there. For the celica its best to use Denso or NGK Iridiums.. i think its the same with the lotus since they are the same engine but im not exactly sure what your owners manual says to use... so use that.
It's very easy and will only take a few minutes. See pages IG-1 through IG-7 (pg 270-276) of the Celica Repair Manual, Vol 2. Snippets below:

Text Line Font Parallel


Next, use a 16 mm (0.63 in.) plug wrench, remove /install the spark plugs. Torque: 18 N m (184 kgf-cm, 13 ft-lbf)

The Celica Manual recommends these spark plugs:
DENSO made, SK20R11
NGK made, IFR6A11

But, you might look around both here and newcelica.org to see what people are using these days.

Have Fun
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I have nothing to add besides advising you to put some dielectric grease in the spark plug boots. It will help insulate and keep moisture out, which has sometimes been a problem.
The only thing I would add would be to direct a compressed air blast into each spark plug hole after removal of the coil packs and before removing the spark plugs. This will ensure that if any loose object has fallen into the spark plug tube it will be expelled and not fall into the cylinder when the spark plug is removed. Also plug each tube opening with a clean rag if you do not put the new plug in right away. There is nothing worse than dropping a tool like a small socket or a small nut or washer only to see it fall into a spark plug tube and into the cylinder. The only way to get someting out of the cylinder is to pull the cylinder head and that is not something you want to do.
The only thing I would add would be to direct a compressed air blast into each spark plug hole after removal of the coil packs and before removing the spark plugs. This will ensure that if any loose object has fallen into the spark plug tube it will be expelled and not fall into the cylinder when the spark plug is removed. Also plug each tube opening with a clean rag if you do not put the new plug in right away. There is nothing worse than dropping a tool like a small socket or a small nut or washer only to see it fall into a spark plug tube and into the cylinder. The only way to get someting out of the cylinder is to pull the cylinder head and that is not something you want to do.
+10000000000000 Do them one at a time and follow the above advice. Its super easy to do.
It's very easy and will only take a few minutes. See pages IG-1 through IG-7 (pg 270-276) of the Celica Repair Manual, Vol 2. Snippets below:

View attachment 129843

Next, use a 16 mm (0.63 in.) plug wrench, remove /install the spark plugs. Torque: 18 N m (184 kgf-cm, 13 ft-lbf)

The Celica Manual recommends these spark plugs:
DENSO made, SK20R11
NGK made, IFR6A11

But, you might look around both here and newcelica.org to see what people are using these days.

Have Fun
Peopl have mentioned the gaps on the spark plugs... is this a real issue? Should I be aware of any particular gap issues?
i agree with all of the above.

The spark plugs come pre gapped but i would look at them closely to make sure they havent been dropped or the gap damaged.
IIRC, we must be careful gapping iridium and platinum so as to not disturb those platings? Is this right?

Also, plugs on most cars can be indexed, so the gap faces the intake valve. You need to mark the socket and try various plugs to do this. I have no idea if it helps for real...
I replaced them on my son's Celica (same engine as the Lotus) last weekend. It was pretty easy. The hole they are in is really deep so I ended up using two extensions since I didn't have one long enough. I also used a spark plug socket with a foam insert that holds on to the plug to get them out and then I used one without the insert to put them back in.
sorry but youre not mechanically inclined if you can't replace spark plugs.. :)
a brief search turned up no warning on gapping iridium or platinum plugs, but mfgrs say there is little need, as these types of plugs will work, at almost any gap, better than a properly-gapped "normal" plug.
Also, plugs on most cars can be indexed, so the gap faces the intake valve. You need to mark the socket and try various plugs to do this. I have no idea if it helps for real...
Does it help? Yes. Will you notice any difference? No. Maybe if you were running a 1,5000 HP top fuel dragster, but for a normal (or even high performance) street car, it will be unnoticible.

I've been known to mark the plugs and swap them around so that I get the most "indexed" combination, but never to the extent that I would swap other plugs for a larger selection (i.e. I only have four plugs - I make the most out of the four, while still understanding that it isn't going to make a difference...).
Does it help? Yes. Will you notice any difference? No. Maybe if you were running a 1,5000 HP top fuel dragster, but for a normal (or even high performance) street car, it will be unnoticible.

I've been known to mark the plugs and swap them around so that I get the most "indexed" combination, but never to the extent that I would swap other plugs for a larger selection (i.e. I only have four plugs - I make the most out of the four, while still understanding that it isn't going to make a difference...).
Wait....my Elise DOESN'T have 1500HP????

I agree w/you.
Just in case anyone else comes upon this page like I did...the SK20R11 were not the right spark plug ... maybe I thought this was talking about the regular 2005 Elise and it's not... I'm not sure- the part number for the NGK's is BKR6E-11 for the copper then some derivative of that number for iridium or platinum. When I cross referenced the part number listed in the Ellise parts manual, I too came up with the SK20R11 ... unfortunately, I didn't compare the spark plugs when I pulled the others out... was surprised and lucky to only find that all the gaps on my spark plugs were closed after a fouled start. The BKR6E-11 started right up. So glad I really didn't mess things up.
Well since hoffaman also brought this back, I'll add to the other great advice which has been posted. When checking the gap on an Iridium spark plug, in the directions it says to use a rod type feeler gauge. I would recommend this, as I found with iridium plugs, you can get the wrong reading when using other types of gauges, even standard feeler gauges. Also if anyone else visits here, whats the best Iridium plug? I'd imagine the cross-referenced NGK..?

Went to NGK site and this is the plug I found:
Iridium IX BKR6EIX-11 Gap - .044
Ive found mostly with turbo cars that copper plugs gapped correctly tend to run a bit smoother in boost areas of the map. On NA cars, only reason i use them is that theyre cheaper and if i foul them when im tuning the car i dont mind cause a new set is less than $10 lol.

Also, the job is simple, so go ahead and do it! Also, the dieelectric grease is a good idea.
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