95 Camaro Z28 LT1 Auto 117k miles.

Hey dudes. I have some bad news about my baby, she's being a very bad girl. A while back (a month or so ago) I noticed my heater wasn't working, so I did the basic coolant flush on the vehicle, refill and went on my way. Heater was back, all was good.

About a month after driving I started noticing my radiator light coming on which I found was getting low. When I pressurized the system and jumped underneath I noticed the radiator drain plug was dripping a bit. No problem, got a new one with a new seal and went on my way.

Since then I noticed the vehicle has a little hesitation when first starting cold, like it's missing. Of course that night I saw a little spark from a wire which when I pushed back on the plug stopped, but the hesitation was still there.

Just yesterday I went around the block, just enough time for the motor to get to the bottom quarter on the temperature gauge. Car drove fine, yet on my last acceleration when pulling in it hesitated hard as if overheating and I shot a wall of steam out about the size of the car, then it evened out. Antifreeze is still leaving, but no leaks. No water in the oil, radiator isn't spewing or bubbling hard, the vehicle has never tried to overheat on me in the year I have had it (nor did it this time).

Is that a symptom of a headgasket going out, maybe letting the antifreeze go straight into the exhaust? I'm almost wondering if maybe that was an issue before getting the vehicle, maybe they put some pooky inside and my flush sent it all out?

Anyway, is this a common problem in older LT1 vehicles? If it is headgasket related and they did pooky it up, I may just have to do it again and risk losing my heater as a HG job is more work than I can do and more money than I can spend. If that is the case, is there a sealant or stop leak brand that is best? Or is there something of a bad design around the cooling system, motor or exhaust that goes out and can be replaced to stop this issue?

Please help! Until I get this fixed up I'm driving a 4banger Corolla and am going nuts in it!! I miss my displacement and comfy seats big time.

 

i'm not sure, but i know this: when the water temp gauge reaches 1/4 after startup, the oil is still not up to operating temp. it takes a little longer for the oil to reach operating temp, which is 212 F and will always be higher than coolant temp.

without an oil temp gauge, the best way to see if oil is up to temp is to look at the oil pressure gauge at idle (or neutral) it should be at the 1/4 mark of it's gauge around 19 or 20 psi

 

How much coolant are you losing? I had a similar prob, I replaced the cap and was good to go! But that is also a symtom of a Bad Head gasket. Any smoke in the exhaust?

 

Does your overflow tank have more coolant in it than the high level mark? I'm looking for evidence that the cooling system is being pressurized by pistons.

Regardless of the above....do the below.

You need to do a cooling system pressure test. Go to Autozone and rent this....



If you have a leak in the system it will not hold pressure....it should hold close to your system pressure(cap pressure) for at least 2 minutes(mine never leaks down). Just don't go above your cap pressure...or you could do damage.

You can also fire the engine up with this attached.....the needle should stay steady.....and as temp increases the pressure will increase....so don't have much pressure on it when firing up the engine cold(around 7 psi)...also don't let it go above your rated cap pressure. I wouldn't let it get hot with this attached. If the needle vibrates wildly, while running, then chances are you have a head gasket problem or cracked block. There are instructions that should come with the tester to tell you how to use it. If not, I can scan mine for you.

I used this when troubleshooting my brother's 1999 Camaro 3.8 V6. He had a head gasket problem. He also never bothered to try and find the reason he was losing coolant. He just kept pouring in new.

I had the oil pan off when I did the test....I pumped it to only 5 PSI and coolant started pouring out the bottom of the block. Bingo, found the problem.

Of course, there were other signs for his problem......





Here is a shot of the rockers from the 13,000 mile replacement engine we replaced it with.....




I had a situation in my Z24(1990 3.1 V6) one time.....

The car would idle funny when cold....but get okay when warmed up. I was also losing coolant out the overflow(closed system). Turned out I had a cylinder wall crack on either 1 or 3....(can't remember which....however my Dad still has the block). It was a hairline crack......when it would get hot, the crack would close up and help to seal up the cooling system. So when cold it was allowing coolant to mix with the combustion and cause it to run rough. This was also pressurizing the cooling system and causing it to overflow.