Which Spark Plugs

[jsmith811]

I have learned the 4runner comes with two different plugs ? not sure why, but what is the consensus or is there one on plugs. NGK or Denso.. 2001 Limited with 94,000 miles, looking to replace the plugs and fuel filter. Anything else that I should look at replacing.

 

[JoeT4R]

I have learned the 4runner comes with two different plugs ? not sure why, but what is the consensus or is there one on plugs. NGK or Denso.. 2001 Limited with 94,000 miles, looking to replace the plugs and fuel filter. Anything else that I should look at replacing.

Make sure you replace the wires as well. Have you also checked the air filter? I just put a K&N in mine and gained a little HP, and also better MPG's

 

[kball]

Lower ball joints and the radiator.

 

[pluton]

Having recently acquired a 97 4R, I set about to change the plugs and wires. The old plugs were 100% Denso and perfectly equally worn/deposited, nice. Obviously, they had been replaced at least once in 16 years. Replaced them with Densos from a nearby online Toyota dealer. 3000 miles later, the Denso plugs are still working fine with no sign of trouble.
The wires, on the other hand, were the original 1997-dated Yazaki wires. Still working fine. Amazing.

 

[PitbullRescuer]

I've always replaced all 6 with NGK plugs and I use NGK wires. Buy you're right, from factory they're 3 NGK and 3 Denso plugs. No idea why.

Don't don't don't and don't use a K&N filter. That oil makes a mess of your MAF & TB.

 

[afg10000]

I don't see what LBJ's and rad have to do with plugs and wires. NGK or Denso is irrelevant, both are OEM, just make sure they're dual electrodes. NGK wires are perfect. Pulled the plugs and wires out of my '01 two weeks ago and whomever changed them had NGK single electrodes in there. Scanguage didn't seem to care but I know it isn't right-

 

[afg10000]

I've always replaced all 6 with NGK plugs and I use NGK wires. Buy you're right, from factory they're 3 NGK and 3 Denso plugs. No idea why.

Don't don't don't and don't use a K&N filter. That oil makes a mess of your MAF & TB.

Gasket breaks by the time it's time to "clean it" anyway. Waste of $$$ -

 

[JayRolla]

I've always replaced all 6 with NGK plugs and I use NGK wires. Buy you're right, from factory they're 3 NGK and 3 Denso plugs. No idea why.

Don't don't don't and don't use a K&N filter. That oil makes a mess of your MAF & TB.

You can use a k&n filter just have to run it dry.

 

[02SE]

You can also use a PROPERLY oiled K&N air filter, with no problems. I've had a drop-in K&N air filter in my 4Runner, since it was two weeks old. That's almost 16 years now, with no MAF or TB issues.

The problem is people that over oil a K&N air filter.

 

[PitbullRescuer]

Or you can use a dry filter and also have no issues.

 

[jsmith811]

Spark Plugs

I found records showing this 01 4runner had plug wires in 2011, I see no record of new plugs though, I can't believe someone would change the wires out and leave the plugs, but apparently they did.

 

[kball]

I don't see what LBJ's and rad have to do with plugs and wires. -

Anything else that I should look at replacing.

Do you now?

 

[rangermenace]

how often do you replace your plugs and wires?
:third:

 

[krenaud33]

You can also use a PROPERLY oiled K&N air filter, with no problems. I've had a drop-in K&N air filter in my 4Runner, since it was two weeks old. That's almost 16 years now, with no MAF or TB issues.

The problem is people that over oil a K&N air filter.

Agreed, I had my K&N filter in my 97' Tacoma for over 100K and now have it in my 2000 4Runner and it probably has 100K on in it since its been in the 4Runner. No issues.

 

[4x4mike]

I'm not a fan of K&N filters but that's for another post. For offroad use there are better choices.

I heard the different plugs are because of the coil packs. The passenger side takes a different load from the coil packs therefore they are different. What those differences are, I don't know. I just got my plugs from the dealer and used what the computer spec'd. I got my factory wires from some online dealer.

If your valve covers are leaking or show sign of leakage it would be a good time to tackle that. You can check the torque on them but make sure they aren't over tightened as they can cause leaks or crack the cover.

Other regular maintenance might be cleaning the TB and IAC, MAF, radiator fluid, PS fluid and clutch fluid if necessary.

 

[Ed_C]

I heard the different plugs are because of the coil packs. The passenger side takes a different load from the coil packs therefore they are different. What those differences are, I don't know.

Nope. You may be confusing the fact that the cylinders sharing the same coil and wire fire both spark plugs simultaneously,but only one of those cylinders are at the right stroke, TDC (Top Dead Center). The cylinder at TDC requires more voltage to the plug since it's igniting a fuel mixture,the other cylinder is at BDC (Bottom Dead Center) where there's no fuel mixture to ignite. It doesn't matter if it's a cylinder at the passenger or driver side.

Here's why they have different plugs. The heads are manufactured or assembled at different facilities. Denso supplied plugs to one facility and NGK to the other.