I recently purchased a 94 runner 3.0 V6 which accelerates on takeoff very poorly. I have heard of this engine to be sluggish, but to the point of taking 60 seconds to reach 30MPH? Will not reach a max speed of over 60 miles per hour. Averaging 8 MPG. I think I may have an air/fuel mixture issue. If this is the case, how do I attempt diagnosing and repairing this issue considering the fact that it is not giving me any trouble codes?

Repairs and test performed so far with no improved results are as follows:

O2 sensor & TPS sensor replaced, cat converter removed and inspected with no signs of any restrictions; rotor, cap and plugs replaced, fuel filter replaced, throttle body inspected and cleaned, MAF sensor tested good.

What am I lacking? I figured all that would be enough to fix the problem. Any ideas of other repairs I can try before resorting to a mechanic or the dealership for help?

 

Rebuild or replace. If you rebuld, you better love toyota and that motor because you are not going to get much more out of it, or relace it with a 3.4.

 

I had the same issue with my truck. I didnt get that poor mileage though. These are a few things I did, they seemed to make a real difference.
I had the valves adjusted, with new valve cover gaskets and intake manifold gaskets. When that was done, I also had the pcv valve replaced and the hose. Also, I picked up some fuel injector cleaner and popped it in the gas tank. Besides that, you might want to replace the plug wires and having the timing belt replaced might make a difference. I did all of the above when I got my truck, so I cant tell you exactly what did the trick. But I was told that a clogged pcv valve can rob power and performance. Good luck man.

Note: I am by no means a professional mechanic, just sharing my ideas and experiences.

 

Do a compression check. Sounds like not all cylinders are firing. What does it sound like? Sputtes?

Could be clogged fuel injectors. Been there done that.

Or take it to a TOYOTA mechanic, someone who knows how to and has worked on a 3.0. Not just any old mechanic who will throw parts at it. Someone who knows how the 3.0 works and common problems to look for.

 

Auto or manual tranny ?





Fred