somebody probably used prestone or some other green coolant, instead of dexcool
if in doubt, replace the pcv valve. It’s cheap. Some of them are marked, which side goes into the valve cover
Open the bleed valves. Fill the radiator with a 50/50 mixture of coolant/water and watch the stream coming out of the bleed valve.
as for that block drain, is something in the way, such as a motor mount or the starter?
To clarify, I’m talking about something like this: http://www.1aauto.com/vapor-canister-purge-solenoid/i/1aemx00137
There’s a tube going from the a valve on the valve cover to the throttle body to that. And another tube labeled as some sort of evaporative line, going to… somewhere.
I’ll have to look at the drain again in the light, I don’t remember what was crowding it.
Rather, that tube has some sort of valve on it that says “evap service point”.
I finally found this helpful diagram:
It looks like I have everything routed correctly, although whether something was attached to the rear nipple remains a mystery. And the transaxle port had a cover on it, so I’m assuming it should remain unused.
I’m pretty confident by 1999, GM was no longer using a vacuum modulator valve on their transaxles. Possibly the engine design is older, from a time when such things were still being used. Yeah, keep it plugged
I’m assuming the mystery port is the “accessory” . . . I’d keep that one plugged as well
The idle seems mostly smooth now, probably about where it was when I first got it.
I replaced some of the vacuum lines, though I don’t know if that’s related. I did get a code for a stuck open EGR valve. I cleaned it out the best I could (though it didn’t seem that dirty to me). So I guess I’ll just wait and see if it comes back.
The oil still looks clean, although I haven’t driven it that much. How long until I can consider this a success?