The Check engine light came on while normal driving on my 99 Toyota 4runner (4 cil-automatic) 165,000 miles. Auto Zone scanned it and I was told it was the EGR valve. I removed it and I noticed it was not too bad. I thoroughly cleaned it. I removed the EGR valve again to replace both gaskets and I noticed there was carbon on the exit side of the EGR valve, which let me to believe the EGR is working properly. I also cleaned the Mass Airflow Sensor and the EGR Temperature Sensor. While cleaning the EGR Temperature Sensor, I noticed the tip of the sensor had what appeared to be a black hard coat that was missing small chunks around it. I couldn't tell if it was carbon build up or a burned out (coating) that should be around the EGR Temp Sensor. I disconnect the vacuum hose going to the EGR and there's suction when I depress the gas pedal; however, I don't know how much suction is required to open/close the EGR valve.
The only thing I've noticed is a "very small" hesitation or "sluggish" when I start driving off, at very low speed; it's hardly noticeable. There are no other symptoms while I'm driving the vehicle besides the engine light on. I’ve also notice a small increase on gas consumption.
New wires, spark plugs, PCV valve were replaced at 125,000.
Sorry for the long thread, but I was trying to be very specific and thorough explaining the problem. ANY assistance would be greatly appreciated!
The only thing I've noticed is a "very small" hesitation or "sluggish" when I start driving off, at very low speed; it's hardly noticeable. There are no other symptoms while I'm driving the vehicle besides the engine light on. I’ve also notice a small increase on gas consumption.
New wires, spark plugs, PCV valve were replaced at 125,000.
Sorry for the long thread, but I was trying to be very specific and thorough explaining the problem. ANY assistance would be greatly appreciated!