Description: Fits 4Runner, Previa, T100, Tacoma PCV Valve - Repair or ReplaceIf your PCV system is malfunctioning, you may notice any of several symptoms: if your Tailpipe smokes or your Engine Idle Speed is high or erratic, the PCV valve or its associated parts may need service. You may also notice that the dipstick in your Toyota won't stay in the dipstick tube, or that your oil cap hisses as the Engine is running. Previa. Federal. T100. 4 cylinder. Tacoma. 4 cylinder. 4-runner. 4 cylinder.