PontiacBonnevilleClub.com

I know this has been covered a few times but it seems like no matter what the symptoms are evereyone points to LIM gaskets but before i start pulling it apart id like a few opinions. Ever since I bought my 98 ssei Ive noticed the smell of coolant under the hood, and when I brought it home the reservoir was low. So I filled it up and checked the oil to see if it was milky, it looked normal so I basically shrugged it of, but now the smell has gotten worse and theres about 2 quarter sized coolant puddles in the garage from parking overnight. I know my valve cover gaskets leak since I can see the oil around them and puddled in the intake on the back side. Or it sure does look like oil anyway. It doesn't appear to be coolant. I checked all around the elbows going to the tensioner and they appear to be dry. And just looked at the dipstick which to me looks just like oil, clean with no sweet smell. But when I pulled the oil cap off there was some milky condensation under it. The condensation under the cap seems to point straight to intake gaskets but it was my understanding that the intake gasket usually wouldn't leak externally and if it were to be leaking internally that it would look like a milkshake on the dipstick. This is where I'm kind of lost. I'll add that I checked under the cap last night after driving 2 miles and it was 30 degrees and drizzling. Idk if cold humidity makes a difference.

If anyone has this same experience please let me know how you approached it. I'd like to save the money and repair this myself but I hate just throwing parts because they could be bad. Especially on a 90k mile car. Thanks in advance

Go to your local radiator shop and have them pressure test the system, or do it yourself if you can lay your hands on a pressure tester.
A leaking water pump is one of the usual suspects, but it could be a holed radiator, bad hose or a myriad of causes.

A pressure test should reveal the source of the leak and save a lot of chasing red herrings.

A little condensation is to be expected on the oil cap if you do a lot of short journeys, particularly in cold weather. A few hours of driving at highway speeds will normally shift it, the oil and the rest of the engine will get up to its designed operating temperature and boil the condensation away, it will also shift any condensation from the exhaust and transmission at the same time.

Roger.

Check the water pump. They will sometimes leak when cooled. What area underneath the car are the puddles.

1. Beside the right wheel - look at water pump
2. Below the right side firewall - look at coolant elbows and heater core hoses/fittings
3. Under front bumper (left or right) - look at radiator and hoses
4. Below transmission on left side - look at thermostat and bleed port on top of housing

Sometimes it helps to drive it and then park it over cardboard to see the areas. After warmed up, look for little seeping points. Sometimes the coolant burns off before you get to looking for the leak.

As for the moisture in the oil cap, it can be from LIM gaskets, but sometimes it collects if the car is not driven enough to get it up to a good temperature and clear the moist air out of the pan.

Otherwise, keep an eye on the coolant and checking the oil as you have been. If the car has the plastic gaskets and they have never been changed, plan on it soon. I have one sitting in my driveway that the owner neglected the coolant issues even after I warned him. Hiss loss, my gain.

+1 on checking the coolant elbows going into the belt tensioner. When mine leaked, I could smell coolant under the hood, and I would get a puddle under the car in the morning.

It seems to be coming from the rear like towards the firewall but I checked the hoses going into the firewall and they appear to be dry. But I just checked under the cap after a 30 mile drive and it was still moist. Oil looks new still

I went ahead and wiped all the moisture out of the cap and neck that way I can check after the work commute again tomorrow. Just for my own assurance, when Dex cool mixes with oil is it pretty obvious? Ive seen the milky mix of traditional coolant in oil but mine looks nice and amber. This oil change only has about 800 miles on it. The old oil was a little dark but it was almost a quart low which seems normal since I have a slight oil leak somewhere. And I'd think that it'd be over full if I had coolant seeping in but idk I guess if its only letting a little in it may not show up. Ive gotta feeling the bearings will notice though lol

Condensation under the oil cap is common in winter because it is extended away from
the hot engine and draws moisture to it. My 96 does it every winter.