head gasket or intake gasket?

[osiris1910]

I've seen several posts about intake gaskets and wonder if my problem is an intake gasket or possibly a head gasket.
Two weeks ago I started my 93 GTP 3.4 and noticed a high (2000rpm) idle. The car would eventually idle down to around 1000 but would idle really rough. It even sounds like its missing a little. After the car warms up I see no problems. Then I noticed a mysterious lack of coolant in the overflow bottle. I then looked and saw white smoke out of the exhaust! So I think head gasket right? I pulled all of the plugs, however all of them look good except for a whiteish powder on them. I believe this is an indication of the coolant being burned off. Also, I change the oil, and it has gas in it! Then it warms up over 32F outside and the car runs great. I fill up the overflow bottle, it gets cold again, and the same symptoms as before show up (with occasional DTC 35 due to high idle). So my question is, is this an intake gasket problem? I don't see why one or more plugs on the same bank would not be steam cleaned. I also don't know why the white smoke would subside after the car is up to temperature. Any help would be appreciated, I really love this car. Thanks.

[twstice]

My guess is that it is the intake gaskets. Coolant flows through the very far two chambers on the very left and right of the intake. My car had a very rough idle and revved way up when it was cold, then died until it warmed up. i replaced the intake gaskets and it runs fine now. im not sure why it subsides when it warms up though, i guess maybe the gaskets and aluminum expand, sealing the leak... i hope this helps, and good luck

[osiris1910]

I'll definitely try replacing the intake gaskets, they only cost $20. I'll post my results after Sunday when I can do the work. Thanks for the help.

[twstice]

np, I hope that fixes ur problem. good luck

[osiris1910]

I pulled off the upper and lower intake. Found "a lot" of brown gummy stuff inside the whole intake. No apparent coolant leak however. (I don't think it could leak into a cylinder unless the intake was internally cracked). I need to replace my PCV valve and basically all of my vacuum lines (broken due to heat damage). I don't know where to look now.

[osiris1910]

Just for anyone who read this before, I think I have everything fixed. I replaced all the vacuum lines, PCV valve, upper and lower intake gaskets, fuel-injector O-rings (all 12), radiator cap, and did a thorough coolant flush. Now she runs like butter! I think the smoke may have been excess fuel or excess condensation (The mufflers need to be replaced because they each a small hole which would allow moisture to circulate through). I found no oil in coolant(that I could tell) or vice versa. So I guess I was just losing coolant through the rad cap. Thanks to everyone who looked at the post.

[kilroypr]

Well my 93 is doing a similar thing and I know that all the hoses and gaskets have to be replaced. remember all fuel injected vehicles are regulated by the air entering tnru the intake manifold. So if there is any kind of leak the car would really idle roughly