4runner4middie

I have a 98 3.4L V6 4runner with 92K mi on it. I have been getting really bad milage lately so i swapped out the spark plugs (with bosch platnium singles, manual said double grounders but auto store said these are the ones to get <-- is that a problme?). I also changed the fuel filter but im still not getting very good milage. Any suggestions? As for the performance stuff i was reading the threads about the magnaflo stuff and was wondering if that would work with my runner. I have also been looking into new intake and am even more confused that i was to begin with so if anyone out there could steer me in the right direction there too that would be great. Thanks.

2ToyGuy

I went to the Bosch Platinum +4's and noticed an immediate performance improvement. They also last about 100k mi between requiring changing, which means they pretty much pay for themselves over time. I also put a K&N air filter in, and that really helped. When was the last time you R&R'd your dist cap and rotor? They can make a big difference in power and mileage too. How about the plug wires? They can reduce mileage and power when they start to fail. How's the oil and filter? Do you change them as often as u should?

Those are just a few ideas I came up with real quick. Let us know how things go!

firemedic

What kind of mileage are you getting?

Captain_Toyota

Bosch platinums are junk. I know of a lot of people who have not had good luck with those plugs.
Id go back to the OEM plugs or even better yet, Denso Iridiums. If you use Iridiums you will be able run them 120,000 miles.
I dont care what some dude at a parts house says, you cant go any better than Denso.
Cap'n

4runner4middie

2toyguy- what kind of K&N did you put in? "When was the last time you R&R'd your dist cap and rotor?" that would be never because i dont know what that is...fill me in plz. as for the oil its lookin just fine, id have to check my papers to see when the last time i had the oil changed, i think im going to do it my self in a week or two.

firemedic- im getting 19 mpg on highway and thats pretty low for me and about 13 around town which really sucks.

cgardner

You don't have a cap and rotor. Your 4Runner has electronic ignition. Some people have seen better mileage by swapping in a new front O2 sensor, but the part is like $100 from the stealer. Gadget at www.urdusa.com has better prices if you are willing to mail order.

cgardner

gwhayduke

Don't get a K&N or any other oiled filter for a 3.4. The oil gets into the airstream and gums up the MAF wire, providing an insulating effect. Use electrical contact cleaner to clean the MAF wire and stick with a Toyota OEM filter to keep it from happening again.

As for mileage: I've never had bad luck with Bosche, but lots of other here have. Put over 100K on a set of +4's in my '95. I may try a set of NGK's or Denso's next time to compare their performance.

Change your fuel filter. Often overlooked. It is NOT a lifetime filter like Toyota Dealers will tell you. Swap it out about every 2 years. And run a good injector cleaner through, like Chevron's Techron.

Clean your throttle body with a good, throttle body cleaner.

Swap out your diffs, tranny and transfer case gear oil (or auto tranny fluid) and go with a good synthetic. Mobil1 or Amsoil.

Get rid of the stock muffler and bolt in the longest Magnaflow they make for a nice mellow, exhaust that flows a little better.

Did all this on my '95 and got it up to 21 mpg before age started getting the best of it. Still gets about 19mpg. I've only done the plugs, throttle body and FF on the '99 and it already gets 22 mpg. I think I can get it up to 23 or 24.

midiwall

The issues I've seen people have with an oiled filter come from OVER oiling the filter. It doesn't take much to be effective, and it's easy to get too much on it.

That said, my Amsoil catridge is working really well after 3 years. I wash it as required, let it dry, give it a LIGHT oiling and put it back in.

2ToyGuy

The K&N I put in is one I ordered from the company directly. It replaces the normal one. Same size, shape, everything, except it's a K&N not a regular paper filter. And as long as you don't put too much oil in them they work great. A little bit goes a long way.

I don't why the Cap'n thinks Bosch Plats are junk. I noticed a very marked improvement In power and mileage when I put them in, and they have gone at least 100k miles in 2 different vehicles so far. To me, that aint junk. They say clean and I've never needed to regap them. I only change them out if one of the electrodes erodes too far for my comfort. That leaves 3 others they're working on. Junk? Ok, whatever you say...

I guess your engine doesn't use a ditributor cap and rotor, so don't sweat them

X-AWDriver

Platinum is a poor conductor of electricity but it's longevity is what most people buy them for and in a stock motor there's generally no issues with them but I prefer just plain 'ol reliable NGKs in my vehicles. Try using platinum in a high boost application and you'll see why they don't work. Even with only 5 more psi over stock (10.5psi was stock) going through my stock turbo in my '93 Eclipse the platinum plugs missfired like crazy so I swapped them out for a good set of NGKs and they held over 20psi with no missfires.

I might try a set of platim=nums and see if I get better mileage but we'll see.