Spark Plugs: '98 Corolla

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Howdy there...

Just replaced plugs in my '98 Corolla. What I pulled out were NGK BKR5NKB twin-ground copper core. Specified gap is .044" and these old ones are worn to .060" - .070".

The new ones I bought are NGK BKR5EGP single electrode platinums. I gapped all to spec before installing. I put on new wires and a new PCV valve as well.

Previous owner did meticulous oil changes but he says he doesnt think the plugs were ever changed. I'm surprised that the car was still running if that is true. It has about 189,000 miles now.

Just looking for feedback.. were those stock plugs (possibly?) and is there any problem with the new ones I chose?

Also I took off the oil filler cap while the car was running and there was a significant amount of air blowing out, way way more than on my '96 4Runner V6 w/ 211k. I guess this indicates blow-by. The car is very good regarding oil consumption, considering what I've heard for this model... Seems to burn just over a quart in ~3000 miles.


Thanks
 
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I would do kreen treatments to stop consumption from getting worse. Clearly the rings are not in great shape from that amount of blow by.

My 2003 one shipped with iridium plugs. You might want to check if 98 was the same thing.

EDIT: Never mind, the 98 corolla specifies:

Quote:
Spark plug type:
DENSO K16TR11
NGK BKR5EKB-11


So, you do not have factory plugs.
 
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There is a tag either on the hood or the passenger side of the head. Your 98 is Double Platinum. Just before the switch to Iridium. If it were me I'd use Iridium.

The 98-02 Corolla 1.8L I4 has a piston design flaw. Too few piston oil return holes that are too small. They clog after a while and when they do, oil scraped by the piston rings has nowhere to go but the combustion chamber. Oil consumption is a quart every 600-1500. The fix is a teardown and a few holes drilled, put the piston back. 80% of the corollas in this year experience the problem after 100k. Those that don't ran synthetic oil. Synthetic oil is a MUST! for your engine to prevent this from happening. Coolant is important too, the engines are known for hotspots.

Hope its not a 3 spd auto.
 
My bad, typo on the plugs -- BKR5EKB is what I pulled out.. so its the factory spec.

Regarding the oil consumption issue, I've read up on it, but my engine doesnt seem to be so bad.
 
Maybe I'm really old school, but a quart in 3k for an engine with 189k simply isn't worth worrying about. I'd be proud
cool.gif


I wouldn't personally treat it with anything except maybe the synthetic oil as suggested.

Just my dos centavos.
 
On a '98 with that kind of miles, I wouldn't worry about that consumption (most manufacturers won't even consider warranty work until you're at 1 QT every 1,000 to 600 miles...). I wouldn't do much to the engine either, I would just use a synthetic (as leakyseals recommends) to keep it clean and enjoy your well-kept car!
 
You can buy a lot of oil for the cost of doing the fix. Given the mileage on the car, I'm not sure it would be worth it.
 
How easy or hard did the plugs come out of the head? I want to replace the original plugs on my wife's 2002 Corolla but I don't want to open up a can of worms.
 
The common response is "just use cheap oil". That mentality is what caused the clogged oil return problem. If you notice his signature you will see why his oil claim doesn't seem so bad. The T5 15w40 HDEO is not flowing to the rings, most of it is flowing through the oil pump release valve back to the sump. He's a new owner, he will soon find its more than he thought and nothing will stop the consumption short of freeing those holes. Why we sell. Why I have 08 GP not 00 corolla in my sig now. adding oil, driving around with oil, always worrying about it drove me nuts.

Sorry for sounding so negative.
 
Originally Posted By: Bottom_Feeder
How easy or hard did the plugs come out of the head? I want to replace the original plugs on my wife's 2002 Corolla but I don't want to open up a can of worms.

So long as you don't do the work hot your fine. They come right out. The aluminum is soft, so do it cold. Use Iridium's
 
Originally Posted By: NilsonCain
Howdy there...

Just replaced plugs in my '98 Corolla. What I pulled out were NGK BKR5NKB twin-ground copper core. Specified gap is .044" and these old ones are worn to .060" - .070".

The new ones I bought are NGK BKR5EGP single electrode platinums. I gapped all to spec before installing. I put on new wires and a new PCV valve as well.


Isn't there a sticker under the hood telling you that you need to use double electrode plugs on the car. I'm pretty sure that's what my gf's daughter's Corolla said when i did her spark plugs last year.

BC.
 
@LeakySeals: Those factory double-ground plugs are just copper (I serviced a lot of these corollas and I have a few used ones on hand for show-n-tell).

@ OP: you can replace them with better quality plugs such as single ground platinum or iridium and they will do just fine.

Corolla engines are quite easy on the plugs so no worries on them whether you have to go with single or multiple ground plugs or not.

Q.
 
Originally Posted By: LeakySeals
The common response is "just use cheap oil". That mentality is what caused the clogged oil return problem. If you notice his signature you will see why his oil claim doesn't seem so bad. The T5 15w40 HDEO is not flowing to the rings, most of it is flowing through the oil pump release valve back to the sump. He's a new owner, he will soon find its more than he thought and nothing will stop the consumption short of freeing those holes. Why we sell. Why I have 08 GP not 00 corolla in my sig now. adding oil, driving around with oil, always worrying about it drove me nuts.

Sorry for sounding so negative.


The info on "clogged oil return problem" is very true and this is why I recommended Kreen treatment before it gets any worse. I was able to completely stop oil consumption in my corolla when it started circa 75000 miles. I was successful because I reacted early and did many different things before I succeeded.

I also noticed that the OP is using quality synthetic oil, which is a good thing in this car. He used some 15W40 oil only to bring viscosity up.

IMHO, even straight 15W40 would not be a problem in this car, this engine runs very hot on hwy (especially pistons). I would not recommend it for short trip city driving though.

One additional advice: keep oil level 0.5qt over the full level all the time. Later toyota revised the corolla dipstick to deal with the oil consumption. It was one of many things that worked for me.
 
Do you have the owner's manual?? I had a '98 and I'm sure the manual said to use the dual ground plugs and not to use single ground plugs.
I always got plugs from the dealer, the price was inline and they were OE plugs. I had no problem with the car for 150k miles, no oil consumption problem.
 
Hi folks...

The car is running much better with the new plugs... noticeably quicker to start and I don't have to shift gears like I'm on a 2-stroke MX bike any more.

AFAIK the only real reason some engines spec dual ground plugs is for longevity in waste-spark ignition systems. Whatever the case, I've noticed a real improvement with the new plugs and if they happen to only last 30 or 40k... I don't care. They're cheap and takes literally 10 minutes to change them.

As far as the oil consumption, I have pretty reliable information that the car doesn't have a history of using much oil, and I have not noticed any consumption worth mentioning either. The current fill is a mix of 5w20 and 15w40, which lands in the 10w30 range, so overly thick oil isn't masking anything.

I know that these engines are indeed known for burning the oil, and the reasons for that, but at 189,000mi this one doesn't seem to have a problem.

I have a 150 mile daily commute, about 80% interstate, and the rest highway. The car is 5-speed but I do drive 80-90MPH on the interstate so the RPMs are still a bit high. The car is guaranteed a bare minimum of 750 highway miles per week, so it definitely gets driven.

When it's time to change the oil I plan to use only full synthetics going forward, but nothing super expensive. I don't care for extended OCIs but the fact that the car is subject to extended high speed/high temp conditions, along with its susceptibility to oil coking in the pistons, is enough to warrant the few extra dollars.
 
Originally Posted By: NilsonCain
Hi folks...

The car is running much better with the new plugs... noticeably quicker to start and I don't have to shift gears like I'm on a 2-stroke MX bike any more.

AFAIK the only real reason some engines spec dual ground plugs is for longevity in waste-spark ignition systems. Whatever the case, I've noticed a real improvement with the new plugs and if they happen to only last 30 or 40k... I don't care. They're cheap and takes literally 10 minutes to change them.

As far as the oil consumption, I have pretty reliable information that the car doesn't have a history of using much oil, and I have not noticed any consumption worth mentioning either. The current fill is a mix of 5w20 and 15w40, which lands in the 10w30 range, so overly thick oil isn't masking anything.

I know that these engines are indeed known for burning the oil, and the reasons for that, but at 189,000mi this one doesn't seem to have a problem.

I have a 150 mile daily commute, about 80% interstate, and the rest highway. The car is 5-speed but I do drive 80-90MPH on the interstate so the RPMs are still a bit high. The car is guaranteed a bare minimum of 750 highway miles per week, so it definitely gets driven.

When it's time to change the oil I plan to use only full synthetics going forward, but nothing super expensive. I don't care for extended OCIs but the fact that the car is subject to extended high speed/high temp conditions, along with its susceptibility to oil coking in the pistons, is enough to warrant the few extra dollars.


That sounds like a good plan, what syn oil? QSUD would probably be a quality low cost synthetic for your short OCI's.
 
Most likely Pennzoil Platinum or the QS from Advance Auto... stuff is dirt cheap!

May try out some high milage stuff too, perhaps the Valvoline NextGen High Milage if I can get a good deal.

I want to change the trans oil this weekend also... I bought a couple quarts of Advance Auto synthetic 75w90 for that. I'm sure that has never been changed before either.
 
Originally Posted By: NilsonCain
I want to change the trans oil this weekend also... I bought a couple quarts of Advance Auto synthetic 75w90 for that. I'm sure that has never been changed before either.

Not sure if it's the 3-speed auto or 5-speed manual, but I distinctly remember the Chilton's manual I was looking at last weekend for my wife's Corolla said there are TWO drain plugs in the tranny. I'll look again tonight to be sure.

The 4-speed auto (what hers has) only has one.
 
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