1994 4runner automatic. I slowly accelerate onto the freeway and the 4runner is scary slow. It makes a grinding noise when I floor the pedal and it goes to 4500 Rpms. It doesn't use the RPMS to its advantage meaning it will not even accelerate when at 4500 rpms. It only does this occasionally and other times it runs okay but not good.
It will not go faster than 55 mph at all and If I try to make it go faster , it bogs down and slows way down. I have pulled engine codes and there are none!

 

Grinding noise from engine? Belt or alternator pulley? Tranny? How does the tranny fluid look? Correct level?
Does the grinding noise occur at any other time? How does it sound at idle?

Just probing to see if the issue can be narrowed down a bit....

 

1st thing I'd do is tune it up... And just so you know, it aint cheap but the best parts are OEM.


2nd is figure out if it's engine or tranny related...

You can also change your tranny fluid and see if that helps...

It may not cure it but it might can separate it so you know.


If no change after that, keep an eye on your cat and see if it cherries after a drive.

 

does it have a clutch??
can u smell burning?

 

No clutch, OP said it was an automatic in 1st post:

 

sorry i didnt see that..
id lift the wheels up and hear if the ddrums are dragging or ebrake is one.

 

I would look at the fuel filter as a possible sluggish response as well. Change the fluids, TPS sensor as well. Check your timing to see where it is at as well. Then tune up as stated above.

Good luck, let us know what you find.

 

Well the tranny fluid smells burnt but I am afraid to change it because I cannot afford a new tranny? I guess another question is... Is it possible the tranny will be destroyed if that need be the problem and the fluid gets flushed?
Still It feels like the problem is Strictly in the engine as if it were overloaded and looses a ton of power occasionally. It feels like there is no torque at all. Sometimes I try to accelerate on flat ground and the pedal is to the metal, but it will decelerate and slow down instead of picking up the speed.

 

when you're hearing grinding noises and smelly tranny fluid, i doubt the motor is to blame.

 

thank you I have done everything except the TPS... and Timing. I had a full tune up, fuel filter, and I have a feeling it is EGR related, or fuel related, or the thermo vacuum valve which is disconnected from the fuel canister and the air pressure regulator. the TVV valve is located behind the engine against the firewall. Could that emmisions piece be the cause of it all?
MY engine seems to be starving for fuel, and is shutting itself down...

 

MY engine seems to be starving for fuel, and is shutting itself down...

 

thank you I have done everything except the TPS... and Timing. I had a full tune up, fuel filter, and I have a feeling it is EGR related, or fuel related, or the thermo vacuum valve which is disconnected from the fuel canister and the air pressure regulator. the TVV valve is located behind the engine against the firewall. Could that emmisions piece be the cause of it all?
MY engine seems to be starving for fuel, and is shutting itself down...

 

well now you're changing the story LOL

went from grinding noises, to a motor starvin for fuel.

if you think it could be the EGR, remove it and see how it runs?

 

do these sound like symptoms from the Throttle Position sensor?? Or fuel pressure regulator? Or are they EGR symptoms??

 

Will the engine still run 4500 rpms under a load driving? If it will, it seems more like it would be the transmisson. Have you ever driven a vehicle that had a transmission that slipped so we can rule the transmission out? Basically the motor will rev but the vehicle will not pull well. The harder you push the pedal, the motor will rev, but the vehicle doesnt go with the engine speed. Hope that makes sense.

 

yes the engine will run 4500 rpm's under a load

 

Then theres something wrong with your transmission..
Most likely got hot and burned up the clutches in the auto.
look into a 5 speed transmission swap.

 

ur transmission is shot is what it sounds like, if u change the fluid it will slip more and just give u less power, it sounds like u need to start looking for a place to rebuild it or find a good used one, or do a 5 spd swap.

 

Will the engine still run 4500 rpms under a load driving?
What do you mean by under a load?

 

Sorry but I am confused as to what you mean by under a load?