Grim Reaper
Expedition Leader
Idle is smooth except its gone back to revving up to 2000.
NEVER disconnect the battery without reading the codes first.
You have lost any information it could have offered as to what caused the problem. Run it for a while and read the codes as the first step.
Remember a code is not necessarily where the problem is but where the ECM detects a reading out of range. Example. A EGR problem will often throw a O2 code because the actual reading is outside the expected reading. The code is where to start diagnostics for the problem. No part should be purchased till the diagnostics are done. There have been many a o2 sensor bought that didn't fix the EGR problem.
A surging rev when foot is on the brake or just steady?
Surging when applying the brake is idle set above 850rpm.
A vacuum leak will NOT cause the idle to go up it will stall at idle. Sounds like one of the following, the throttle is sticking, the Idle air bypass up under the plenum is screwed up,TPS is bad or the the AFM is hanging .
The AFM and ONLY the AFM controls the fuel. When you push the throttle the TPS is telling the computer how far you have opened the throttle. The AFM door being pulled open is what adds the fuel. No air going through the afm (vacuum leak) would cause the motor to lean out and at idle it would stall because the door in the AFM would not open enough to keep the fuel pump on. The computer then looks for the AFM to catch up with and equalize with the TPS position.
A Bad TPS (from getting carb cleaner in it) Would play hell with it. Getting a CEL? Read the code.. Read the codes regardless as some codes do not throw the light. Look for it to throw a code for Idle circuit or a code showing an out of range reading between the AFM and TPS. It may populate as a AFM code not TPS.
I am thinking you need to look at the throttle and TPS first since that is the last place you were tinkering. http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=100 has how to meter out the TPS. Supra 7MGE has the same values and that is a much easier to use online manual.
Here is a 4Runner manuals. http://www.ncttora.com/fsm/index.html
If the TPS looks bad As long as it hasn't been damaged the gasket between the throttle and the intake is reusable. You will have to take the throttle loose to change the TPS. I bought a TPS from Autozone that came in a "Wells". Wells apparently is buying these from Toyota or ND as the TPS was a ND with Toyota logo. It was $90 verses the dealers $180 quote.
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