a slow loss of coolant is never good... are you sure your actually losing coolant? and its not going in/out of the engine and the overflow res is just at diff levels. as long as your above the minimum i wouldnt worry about it. your oil isnt milky and ur car runs fine?

a sweet smelling exhaust could result in the engine running rich also, or your smelling tranny fluid burning. just 2 other options.

 

A few points about coolant in the oil:

• Just because the oil isn't milky doesn't by any stretch mean there isn't coolant in the oil.
• Ethylene Glycol based coolant is bad-bad-bad for engine bearings; concentrations of as little as 2% can start damaging the crank and cam bearings.
• There are some companies which sell Ethylene Glycol test strips; simply apply a few drops of oil to the strips and they will indicate the presence (or absence) of coolant.
• Used oil analysis (UOA) testing will also identify coolant in the oil; the big advantage of the UOA test is that, unlike the Yes/No indication of the test strips, this test can provide you with a percentage of contamination.

 

Take off the radiator cap & check the smallest disk in the middle. It should pull down pretty easy, it doesn't have a very strong spring. Make sure there's nothing obstructing that. That small disk is the "vacuum-break" for the system.

 

You can buy/rent the tools to perform a cold pressure leak test of the cooling system. This will disclose external leaks visually, and if bleed down occurs w/o any leakage, it probably going past head gasket into a cylinder.

When I had similar situation, I pulled all plugs and turned engine over w/ starter. A geyser erupted on one cylinder. New head gasket resolved problem.

good luck

 

The radiator cap is pretty much brand new, bought it last week.

I just finished taking the intake manifold out, and noticed that along with an insane amount of dirt and those "helicopter" seed things, there is also what looks to be oil on the rear head, closest to the cabin, but not the one closest to the front of the car.
Unfortunately this could be multiple things on this car. A year or so ago I replaced the valve cover gaskets, they were leaky. I did the front one, but put off doing the rear one because it was a pain to get the valve cover off with all the lines attached to it. It took me about a few months longer to get that one off. This could be oil still from that I suppose, but it's hard to tell really, and I didn't put in any of that uv dye in to my oil before doing this to check unfortunately.


Before I try and do the head gaskets (which would likely be a two day job on my car, and I'd might as well do the timing belt and water pump while I'm there) I'll see if I can find a leak-down tester to rent somewhere. I'm not sure, but I don't think autozone rents them, at least the one by me.
There is also oil or soot, hard to say really, on the intake manifold by the valve ports, and a little in to the valve ports. I'm going to clean it up and have already ordered new gaskets for it. With how dirty everything is in here, it's really hard to tell where anything is coming from. I almost need to give this thing a solid cleaning, run it for a while then pop everything out again to check it out.

 

First off, sorry for the double post.

I have the intake manifold and related parts out now and waiting for gaskets to arrive (I'm doing the two valve gaskets, and I broke the throttle body gasket taking the thing out, so that too.). While that's out, is there anything I could look for that might give me a clue if a coolant leak is occurring around here? I gave the area under the manifold a massive cleaning, there was gunk and assorted debris that I had to remove, and it's all nice and shiny now. It was relatively impossible to tell what the gunk was, or where it even came from, looked like old oil, but who knows how old or if I had fixed the problem before. So should I look for anything before I bolt it all back up, or just wait to see if it still leaks then do a leak-down test if it does?

 

Time to find a leak is before taking system apart, not after. You'll have to hope you fixed the problem.

good luck

 

Totally agree with TX.

A "block check" tests for exhaust gas in the coolant system.....a ~$35 test and your will know if the HG is blown....~25 for the tester and ~7 for the fluid. There are other tests that can confirm a bag HG but I like the block test.

 

True, I agree with both of you. Normally I'd test before changing parts, but I've been wanting to clean my IM for a while, and this was an excuse to finally do it. The gasket replacements are just an added bonus!

I think AutoZone actually rents the block tester, I'd just have to buy the blue fluid stuff. So basically, if the liquid changes color, it pretty much guarantees the HG? I've never done a test like that.

 

Pretty much it......the chemicals (test fluid) detect exhaust gas in the coolant....not too many places that can happen.