Toyota 3.4 Power Loss

[cjfj80]

I have a 96' 4Runner 3.4L 154k on it. Only thing not stock is the K&N Intake kit.
I just got it 2 weeks back and and having some power issues. I drove it over Parleys Canyon yesterday and it fights to do 50mph up those hills. It bogs out real bad if you push the gas to hard as well. The reason I am asking is my brothers is a 97 with pretty well same everything that will do 70 up and over no problem. Any suggestions? I know the 22r really well but never have had one of these 3.4s.
Already done:
Fuel Filter.
Cleaned the air filter.
Checked compression on the cylinders, 155 all the way around.
Ran the Lucas fuel system cleaner through it.

 

[Spork]

Check engine light on?
Cleaned the Mass Air Flow sensor?

Other than those simple things what about a plugged catalytic converter? The mileage is getting up there so it could be possible.

 

[SAMI]

Auto?

 

[chans]

Still on the original timing belts?

 

[cjfj80]

Check engine light is off, I did clean the mass air flow, it is an auto tranny, I know the timing belt was changed at 90k so I'll check it this weekend. I have no idea on the cat except I live in Heber so I don't have emissions so I have never thought to check it.

 

[SLC97SR5]

You've already addressed the common issues with the 3.4L.

-Fuel filter
-Cleaned the MAF, easily fouled from the K&N


Are the plug wires original? They will be printed with the manufacturing date on the wire. If they have 150k+ I'd replace them, it smoothed out my cold idle and eased starting when I did mine. Also check their routing in the clips above the timing cover.

What do the plugs look like? Again, use the factory denso or NGK.

Do you have a scanner to verify the TPS is showing WOT and does not have dead spots on it? It should read from 12% at IDLE to 76-80% at WOT.

It's possible you have a coil pack going bad but these will throw a code pretty early on.

These engines love factory parts and can be very picky towards regular parts strore stuff.

 

[NOTATOY]

Caleb I have had a couple tacos, and the cats are known for going bad. I had to
replace the one on my 4 door. Urd makes an 02 eliminator kit, where you don't have emissions I might consider cutting them out. I thought about it with my supercharged 3.4 then I decided to sell it. For sure check the plugs and wires, and fuel filter. I also ran mine with the power ext. button on the dash on, it helps with the shift points.