3.0 rpm up and down

[MacGyver1979]

My wife's 89 3.0 runs like a scalded dog. The idle was set way too high when we got it, and I turned it down after replacing the TPS. It starts fine, runs fine.
The problem when only applying a little gas at the peddle constant pressure the engine RPM's surge up and down like if you were tapping the gas peddle to the music. It did this before I did the idle adjustment and TPS.
Also the gas peddle is often stiff in the up position, iv lubed everything, but still stiff. Its to the point that from a stop she pushes the peddle fairly hard and it breaks free and the 4runner jumps to life.
Any ideas?

 

[lmkr67]

My wife's 89 3.0 runs like a scalded dog. The idle was set way too high when we got it, and I turned it down after replacing the TPS. It starts fine, runs fine.
The problem when only applying a little gas at the peddle constant pressure the engine RPM's surge up and down like if you were tapping the gas peddle to the music. It did this before I did the idle adjustment and TPS.
Also the gas peddle is often stiff in the up position, iv lubed everything, but still stiff. Its to the point that from a stop she pushes the peddle fairly hard and it breaks free and the 4runner jumps to life.
Any ideas?

Have you tried to manually work the throttle at the throttle body to eliminate the resistance being in the cable or pedal ? Most of the time on the 3.0 the rolling idle is a vac leak. the egr vac modulator having an internal leak is a common cause of rolling idle

 

[MacGyver1979]

Have you tried to manually work the throttle at the throttle body to eliminate the resistance being in the cable or pedal ? Most of the time on the 3.0 the rolling idle is a vac leak. the egr vac modulator having an internal leak is a common cause of rolling idle

yes, I cleaned the throttle body, worked the throttle by hand and lubed everything. where is that egr vac modulator located?

 

[nicnmike]

yes, I cleaned the throttle body, worked the throttle by hand and lubed everything. where is that egr vac modulator located?

When you cleaned the throttle body, did you remove it and clean out the coolant passage? They can get pretty junked up and that can also cause a pulsating idle.

 

[MacGyver1979]

no I removed the intake boot and used throttle body cleaner and a tooth brush.
My wife also complains about it drinking gas, dont know the MPG, no speedo.

 

[nicnmike]

no I removed the intake boot and used throttle body cleaner and a tooth brush.
My wife also complains about it drinking gas, dont know the MPG, no speedo.

If you have a smart phone, you can download a speedometer app that uses gps to calculate your speed. It's pretty accurate. My speedo recently died and I've been using it. I prop up my phone on the cup holder, or pull out the ashtray and prop it up on that. It will also monitor distance, so you can check mpg on a road trip.

 

[Bad_Vision]

I don't know about the 3.0 TPS but I know the 22 RE TPS needs to be calibrated. Maybe the 3.0 is the same?

 

[Ahlem]

Also check your timing. If you are too advanced, you will see surging.
I had exactly the same situation and things settled down quite a bit when the timing wasn't 25 degrees advanced. I did have to adjust the idle speed screw up a bit as I retarded the timing but everything is much happier now.