Robinhood150

Last weekend when I went to the mountains I went up this really steep, long grade. At one point, when I had lost my momentum, I got bogged down to 30mph and couldn't go any faster. I was already in 2nd gear (auto tranny) and 1st gear would have been too low.

So I figure I need a tune up to get back some power and mileage. Everything under the hood is stock and ORIGINAL with the exception of the scheduled maintenance items such as timing chain, sparkplugs etc. The last major maintenance was the 120k mile service that toyota did, and that was 35k miles ago. Also, they replaced the heads and re-shimmed the valves around 130k miles.

I'm already going to clean out the throttle body. What else should I do? spark plug wires? spark plugs? fuel filter? etc?

thanks,
Steve

UKMyers

Steve,
Usually when I do a tune up I'll change the plugs, wires, airfilter, oil and filter, and possibly the fuel filter if it needs it. Usually a clean air filter and new plugs will make a noticable increase in "pep". Also a good thing to check if you have the ability is the timing. I am not a Runner expert yet because I have only had mine about 9 months but I have read in other posts that the timing is very critical on the 3.0 for good power! Hope this helps

jx94148

Distributer cap and rotor. And the often forgotten spare tire chain or cable mechanism.

HALMAN

Hey Robinhood, when I do my tune ups I usually time them around my oil changes, just so everything is "like new" again.

Plugs, wires, air-filter, gas filter(only changed her once,PITA(pain in the Ass)), Rotor, dist cap, timing-which includes setting the RPMs. Thats about all you can do yourself, I suppose.

I have the same problem you have with the power going up hill on my '93' 4Runner. What I did is, I bought a compression tester and took all my plugs out and ran a compression test on all cylinders. Damn if I wasn't only running on 4 cylinders!!!:cry:

#1 cylinder 20psi. and the #4 cylinder in at 60psi. All other cylinders are at 170psi. which is within the specs. for my 3.0.

So whats do I thinks its coulds be? well, could be Head Gasket, or it could be the rings (don't thinks it's the rings due to NO oil loss, plus I squirted some oil into the cylinder and redid the comp. test and no change) or it could be stuck valves. :pat:

I hoping its the gasket, but I doubt it is. If it's the valves they'll have to be removed and sent out to a machine shop, which could take a week or more, depends on how busy the shop is. I made an appointment with the dealer (a different one than the last one) for Monday. I tried to get some local mechs, but they all said they were booked until end of August.

I'll let you know what the mechs say Monday, should be interesting.

I hope this helps you, seriously check your compression if the "tune up" doesen't help, you may be surprised as I was!

MNRUNNER

When you guys talk about changing the plugs wires and cap. Is replacing the wires and cap as easy as it looks. I mean do you simply just plug the wires in? Also where would you get new wires and cap? Just any old auto parts store or the dealer?

Yoda

Yes it is as easy as it looks. But, move them from the old cap to the new cap one at a time in the correct order.

The folks here like to use factory Toyota cap and wires. I usually go to my NAPA store. I buy the profesional wire set (lifetime guarantee). Anything happens to them, they are replaced. I know everyone at some time or another has pulled the wire off the plug and had the clip end break off. The set gets replaced free.
They are on my Landcruiser, Toyota PU, Cherokee, Taurus and MG.
I also like their caps and rotors because they have brass contacts (at least on most I have seen). Aluminum contacts oxidize and that white crap gets falls off inside the distributor.

David

Robinhood150

Hey thanks guys, that's what I needed. I'll probably add this to the 4runner FAQ when I'm done.

I hope I just need to clean the injectors and not rebuild the engine. The HG was replaced last year and they did a valve re-shim then too. A compression test might be a good idea though.

Is changing the plugs hard to do? I've heard it's a pain to get a socket in there. Haven't looked yet.

Steve

HALMAN

Steve,
Removing the plugs isn't so bad, it's getting the boots off without breaking them, is what I find a pain. I use a 3/8" drive socket set, with a couple different extension sizes.
Being we have the same year and engine, I can tell you the #5 cylinder and the #2 cylinder are the only ones I have trouble getting off, not enough room. Actually it's not getting the sockets on, it's Ratcheting the ratchet! Watch out for those knuckles!:cry:

The cylinders are numbered as follows:

Firewall.

5-------6

3-------4

1-------2

Front of engine.

What will help you with the room, is to take off the air flow ducts that connect to the air cleaner and the throttle tube. Once removed the 3 even numbered plugs are much easier to remove. This won't help you with the #5 plug, that's the tough one.

It's not hard to remove them, just a matter of loosening a few hose clamps. I also remove the dipsticks, not the tubes.

Good Luck Steve. Don't forget to gap those plugs to .031".

Hal>