I am having trouble with smooth starts on a warm engine now that I changed the spark plugs and have been checking EVERYTHING I can think of. I know the car is running rich because I checked the NEW plugs and they have lots of black residue. Have changed the fuel filter, checked vaccum hoses, measured O2 sensor output, checked for codes, etc.

Anyhow, I unplugged the fuel pressure regulator valve from the suction hose and noticed that now and then a drop of fuel spits out. Is this normal, or is the regulator faulty? Is there any way to check it before I replace it?

 

if your getting liquid gas out of the port where the vacume line connects you are in need of a new regulator. I suggest getting an adjustable regulator. That way you can always keep your fuel presssure right where you want it.

 

I replaced it, it took less than 10 minutes, and the car now runs like a champ. Thank you for your advice.