It is in the corner of the left valve cover on the transmission end of the engine. So for a Transverse mount engine that is the right side of the front valve cover. If it is a longitudanal (traditional) mount it is in the back of the driver's side valve cover. (I can't remember which way a 1991 Deville is, sorry). There is a plasic cover that holds the plug wires (or did anyway if the last person to tune it up took the time to put the wires in them), it also covers the PVC valve. Remove the plastic cover and see the valve.Ralph said:I want to put in a new PCV valve, where the heck is it. Every other car I ever had, they were on the valve cover or the back of the intake manifold!
The 91 FSM has a nice little "fix", timing settings for use with 87 octane fuels for the 4.9L V8.lux hauler said:If the manufacturer recommends 92 octane, use 92 octane. If they don't recommend premium fuel, it's not going to hurt the motor to run it but you're just spending money that you don't need to spend.
There was a discussion on here about this a while back. I'll see if I can find it.