When the engine is running and I pull the hose off of the PCV valve, the engine sputters and quickly dies. I guess it's getting too much air suddenly going into the intake while at idle. Is this expected? I ask this because I was going to do a Seafoam treatment (first time ever), but the engine immediately dies before I do anything. I aborted the effort until I make certain I know what's going on and what I'm supposed to do. I've read that others say they suck a little bit of Seafoam at a time through the hose, but they are able to never let the engine die. So I assume they pull the hose out of the liquid to prevent the engine from dying? Mine just dies immediately. Is there a problem I should look into or does this just make sense and it's supposed to work that way?

My PCV valve is newly replaced so I don't think that's the problem. It rattled before I installed it.

I need to try it again with removing the PCV valve from the engine and see if I can keep it running by putting a finger over the PCV valve end. I don't understand the direction of airflow normally through the valve - which direction should the PCV valve prevent the air from flowing under normal operating conditions?

If you remove the hose from the PCV valve - take a pair of vice grips or other lockable pliers and slightly restrict the amount of air that can get in. I also put a small funnel on the end of the hose and slowly pour in the Seafoam.

Remember to let the Seafoam "soak" in for a bit (15-20 min) with the engine off. Then restart in a well ventilated area - there will be a great deal of white smoke.

Best of Luck.
Andrew

you can also raise the rpm of the engine to 1200rpm or so to prevent it from dying when you unplug the PCV.

That's normal... since the PCV hose goes straight into the intake manifold side via the throttle body connection.. Engine suddenly goes too lean and quits.

I've never heard of anyone using the PVC line, always the brake booster line.

Jeff, I used the brake booster line when doing mine. What's nice about it is you can use your thumb to "gauge" how much vacuum is being lost. Don't stick the hose into the can or you might hydrolock your engine. The vacuum is strong enough that you can just put it up to the opening of the bottle and it'll suck the fluid out.