'94 Camaro, 3.4L, 160k miles. My coolant is disappearing; I have to add about 1qt every 20 miles to keep from overheating. There's not a drop under the car and no milk in the oil, but I do get a lot of white smoke in the exhaust. There's a whistling noise coming from somewhere; maybe from the lower intake manifold, but really hard to tell. I *think* stops if I remove a vacuum fitting from the emissions system, but the sound may just be masked. It decreases in pitch and volume with RPM. The sound stopped completely at one point when I let the car sit for a month, but started up again a few trips later after I pushed the engine hard. The car throws a SES light, usually once a trip, always after the car has warmed up for 20 minute or so, and usually as I brake on the highway after driving several highway miles. It's done it just 2 miles from home, and has gone 30+ minutes without a warning. [This computer won't do the blink codes or take an OBDII, so I don't know what the code is.] The light went away for about 6 months after I replaced the O2 sensors, but eventually returned. In retrospect, the symptoms started about 5 years ago, but it's only gotten very bad more recently.

If I leave the radiator cap off when I first start the car, I don't get any big bubbles, but the level slowly rises (with slow oscillations) until it overflows the cap. Only takes a minute or so for this.

Sounds like either the intake manifold gasket or head gasket could be causing this. Both are obviously a real pain in the *** to replace. Is there a way I can find out for sure what the problem is before tearing the engine apart?

This is not my daily driver anymore; it's been relegated to back-up car and I mostly only drive it to/from the airport or on other errands I don't want to use my new car for and can't use my wife's SUV for whatever reason. Are there any temporary quick fixes I can do? Stop leak or something that may slow the leak and give the car another 5-10k miles?

 

Sounds like its bad enough head gasket that if you pull the plugs all your question will be answered. Also most of your problems would be head gasket not intake.

 

Have the radiator system pressure checked and if a head gasket is blown, it should show up in the test. White smoke coming from the exhaust is a real good indicator that a head gasket is gone. There are all kinds of bottles of mystery juice on the shelves of auto parts stores that claim to seal head gaskets, etc. There are a ton of links on the internet to prove and disprove almost all of them. Personally, If it is a head gasket, I would spend that money on a set of head gaskets and fix it right if you have the tools and time.

 

AMEN. There is no such thing as mechanic in a bottle. The snake oils are for quick/temporary fixes till you can get it done right.

 

Wouldn't a blown head gasket and blown intake manifold gasket both cause billows of white smoke? How would they look different in the pressure test; intake would be negative pressure, and head gasket would be positive pressure?

 

Head gasket will pressurize the rad system and they can find halocarbons in the test. Either way, if you have 160k and are taking the intake off, you might as well replace the head gaskets since you are that close. Otherwise, you might be doing them next month and have to go through all that again.

 

That is how we know its a head gasket. Intake gaskets on the 3.8's is a very common problem but most of the time when and intake gasket fails on a 3.8 it leaks to the outside of the motor not into an intake port. It is possible to leak to a intake running but this would cause a No Pressure in the coolant system. You may even see the hose start to collapse. Like I said that is a very uncommon situation.

 

Eh, nuts. How difficult is it to replace the headgasket? I've got the Chilton's guide, and it looks like a royal pain in the ***, but it's hard to tell just how hard it'll be to get some of those bolts out. Any part of it that's beyond a lazy shadetree mechanic like me, or will some PB Blast and a ratchet set make short work of it?

 

How’s your back? You’re not trying to be a hand model or anything like that? Both of those questions will make a lot of sense when you’re done

 

When I did the ones in a 96 a couple months ago, the hardest part was getting the exhaust manifolds off but PB blaster did the trick. The hardest part of putting it all back together is using the angle torque guage under the cowl to make sure you get the torque right on the NEW head bolts. Bandaids and patients go a long way! Oh wait! I forgot about having to put new plugs in it after getting the heads on, that was a royal PITA.