So I am diving into the 3VZE. Depending on what we find will depend on how far down the rabbit hole we go.

HISTORY: I purchased a decent 95 4Runner a few months ago that now has 240,000 miles on it. The head gaskets replaced in mid 2013 and the vehicle seems to be well maintained from the original owner. I have been fixing misc issues for the past few weeks and am ready to dive in.

Issues
Valve cover gaskets leaking both sides
Oil leaking from rear of engine close to heads (PCV or valve cover?)
Rough idle some low end surging when cold
Unknown PCV condition or age
Possible vacuum leak (vacuum tested low at 12)
Seems to be under powered even with 5 speed 4.56 gears and 31s

Plan of action
Pull upper intake manifold clean and replace gaskets
Test compression on all cylinders
Verify engine does not need rebuild and meets minimal specs
Pressure test cooling system at 15lbs
Replace valve cover gasket and PCV

Any advice or help is welcome. I will update this thread with pictures and progress

here is some helpfull info for other members

 

Valve clearance and adjustment

 

I definitely have some valve noise. I will have to research it a little more and see if I can find the SST some where. I probably should brake down and do the timing belt but I have never done one on a Toyota.




So checked compression on the drivers side with the passenger side plugs in. Cylinder #2 150psi, Cylinder #4 152psi, Cylinder #6 143psi. I will re test with all the plugs and upper intake manifold off but that's not horrible with 240,000 miles IMOP




Putting 15psi of pressure on the cooling system. After a few minuets I noticed it dropped about a pound




The good news is I found a slight leak near the drivers side rear valve cover at the little T fitting. Tonight I will get it fixed and try to pressurize it again.

 

Timing is everything.... send a PM

 

PM's not working, Tried sending you this via PM:

If interested

I have the following leftover my from 95, 3.0L.
Toyota OEM:all new in box
Gasket, Oil Cooler 15785-35010
Washer,SE 90210-22001
Oring 90301-61003
Felpro - Circular Plug ES 72308

 

Few things I would recommend:

• Replace PCV valve as they are cheap
• Replace all your coolant hose clamps as the ones on from the pics look old
• if you have a probe or bore scope (dont know the proper term) take the spark plug of cylinder 6 and check to ensure there is no water in the cylinder. If there is, you have a bad head gasket
• "Oil leaking from rear of engine close to heads (PCV or valve cover?)" That is the valve cover gasket and both half moons might need to be replaced as well

 

Looks like the PCV isn't to bad but I have a new one and the rubber peace so I am replacing it.

The passenger side valve cover gasket was BAD!!! Huge leak all over the side and rear of the motor. I have new valve cover gaskets from Toyota.

Intake manifold wasn't that bad inside or was the TB. I pulled all the plugs and will check all cylinders compression shortly.



It's hard to say if this failed during the intake removal or not but the gasket was still in place on the lower and has two cracks.




Here you can see both cracks.

 

So I was able to check all 6 cylinders compression and the results are as followed.




Cylinder #6 about right for a well used 3vze




Cylinder #4 looking really good




Cylinder #2 still looking perfect




Cylinder #3 that seems really high for a 9.0 compression motor with 240k




Cylinder #1 is slacking




Cylinder #5 and the last one I checked..... Damn it!!!

 

So now what? I guess I am going to start tearing into her. I don't know if I should just remove the passenger side head or the hole motor.

 

Run a cylinder leak down test and see where your compression loss is.

 

Unfortanitly i do not have a leak down tester.

I figured I would pull both heads. Once the heads are off we should be able to figure out if the compression issue is from the heads or rings. It's kind of looking like a burnt valve on cylinder 5 and that might account for the valve train noise. I talked to a local machine shop that has done work for me in the past and they estimated about $400 to do both heads assuming they are not cracked or damaged so that doesn't sound to bad.

If I can keep the price down I may throw a set of LCE headers on but I still need to do more research.

 

Probably will replace the timing belt, water pump, and timing tensioner since I am already in there.

 

Slow progress.

 

Going to work on getting the exhaust manifolds and timing cover off today if I get some free time. I want to see what the timing belt looks like and if the timing marks are lining up or if it has jumped a tooth.

Now as far as preparation I know I am at the very minimal going to need the following
Toyota timing belt ($45 from dealer)
Toyota tensioner ($60 from dealer)
Lower intake manifold gasket (still need to source)
Injectors replaced, cleaned, or upgraded (undecided at this time)
Toyota throttle body gasket (I already have one)
Toyota valve cover gaskets (I already have a set)
Toyota thermostat (still need to source)
Head gaskets (considering OEM gaskets)
Exhaust manifold gaskets (still need to source)

Any thing else I should address?

 

Looking like somthing has been leaking under the timing cover.




Well it's safe to say that is one worn timing belt.




Good news is the cam marks look like the are lining up.

 

Regarding the stuff you still need, if the dealer doesn't have them, I would go aftermarket, RockAuto.com specifically as they have good pricing.

For the injectors, if they are original, I would replace them with a good OE or OEM set. If you get upgraded ones, you really wont see a difference with performance.

If the Head Gasket is still in good shape, I would just do a tune up and replace the other items mentioned:

"Probably will replace the timing belt, water pump, and timing tensioner since I am already in there. "

• Plugs
• Cap & Rotor - (dealer sells these for about $40 - $50)
• Wires - either Denso or NKG
• Distributor if it needs to be replaced.
• Oil change

 

Yeap on top of the tune up stuff.
New oem plugs
NGK wires
Cap
Rotor button
Toyota coolant

I was more referring to seals, gaskets, etc.

 

She is getting there

 

Every thing is out of the way. I am about to start pulling the cam sprockets and cams. Any advice is welcome

 

Cams are out, all head bolts removed but the exhaust manifolds are fighting me. I was able to get the three bolt flange off on the exhaust. Now I need to get the six bolts out of the exhaust manifolds and the heads should be out.

Good news is the cams look like they are in good shape.