Need help finding source of coolant leak

[Swoop]

I took the car in to have the check valve installed to solve the coolant gurgling sound.(TSB #09-01-37-001). Its been two weeks and I'm still smelling coolant when the car is hot. I've checked the checkvalve fittings for leaks and everything appears dry. I know they had to drain and refill the coolant for the install. My 4th gen V6 had a bleed screw on the top of the engine that is used to bleed air after coolant fill. I was wondering if my new car has a similar bleed screw that may be seeping but don't see anything reembling such on the top of the engine.

I'm looking for suggestions as to where it might be leaking, knowing that the dealer probably caused the leak during the install (no smell before the service). The service I got last time was disapointing and I'm trying to avoid taking it back in. I don't have a service manual yet, so I don't know what the specifics are regarding a coolant drain and fill. Any advice or ideas are welcome. thanks in advance, Chris.

[Big Brunsy]

well, it's under warranty yet, and I'm sure there are other dealers around if you don't like the one you tood it to the first time right?

[Black Friday]

Mine was doing the same thing. Took it in for the fix and smelled the fluid after, but couldn't find the source. It's on it's way to Lingenfelter, so everything will be changed when it gets back. If you find out the source, please let me know as I couldn't find it i either.

Mark

[DangerZL1]

When I changed my coolant in my Honda, I was still smelling it after a couple of weeks. I thought I may have done something wrong and had a leak, but I've done this as regular maintenace on all my cars and never had a problem before. I forgot that I usually wash the engine and radiator area with mild soap afterwards. I did this and the smell disappeared. It's worth a try if there isn't a leak vs taking it back to the dealer. The dealer probably drained the radiator to install the part.

[Dave Coyle]

I have a few questions about your "gurgling" sound, is your car running at the "normal" operating temp and is the gurgling happen only after you shut it off or is it doing it only when it is running? The reason I ask is because if it is gurgling only when it is running, I would watch for a head gasket problem. Keep your I on the oil also for any antifreeze getting into it. Also, you didn't say if your coolant is going down too. Stand behind your car and see if you smell the anifreeze smell coming from your exhaust. If you do, make sure your dealer knows this because this is a sign of a head gasket going south or cracked head. Just some things to think about.

[Swoop]

It's my fiance's, I never heard the gurgling personally, she heard it and saw the TSB on this forum, and had it fixed during a routine visit. I have rinsed down the engine and am still smelling it. No sign of coolant in the oil so far and no smell coming from the exhaust. So far the coolant level doesn't appear to be dropping. I was assuming the dealer might have spilled some, but have become more suspicious of a leak due to the persistant odor.

The dealer put 13 miles on it taking it to their paintshop which is 2 miles away. I'm trying not to jump to conclusions such as the car being thrashed by the service guy and blowing a head gasket. I know its prob not the case, but I can't help but wonder how those miles got on the car. The guy at the desk told me "road testing to make sure the problem was fixed". Hmm, and he didn't notice the reaking odor of coolant?? I hope I'm just being paranoid.

[Oldrocker]

When you start messing around with heater hoses you always risk heater core leaks due to damage caused by agressive twisting of the hoses from the core inlet/outlet nipple. A heater core leak will usually cause a sweet smell from the vents and could cause the windshield to fog up when using the defroster. You could also find coolant under the floor mat or carpet if the leak is big enough. I'd take it back and have it checked out, you shouldn't still smell coolant after that long. If the job was done right you shouldn't have smelled any at all. Also a long test drive to make sure the cooling system is working properly is a good thing.

[mtcwby]

Originally Posted by Swoop

I took the car in to have the check valve installed to solve the coolant gurgling sound.(TSB #09-01-37-001). Its been two weeks and I'm still smelling coolant when the car is hot. I've checked the checkvalve fittings for leaks and everything appears dry. I know they had to drain and refill the coolant for the install. My 4th gen V6 had a bleed screw on the top of the engine that is used to bleed air after coolant fill. I was wondering if my new car has a similar bleed screw that may be seeping but don't see anything reembling such on the top of the engine.

I'm looking for suggestions as to where it might be leaking, knowing that the dealer probably caused the leak during the install (no smell before the service). The service I got last time was disapointing and I'm trying to avoid taking it back in. I don't have a service manual yet, so I don't know what the specifics are regarding a coolant drain and fill. Any advice or ideas are welcome. thanks in advance, Chris.

The LS3 doesn't have a bleed screw. The small hose that goes from the engine to the radiator above the upper large radiator hose is a steam line that vents any air from the engine to the top of the radiator.

Wash your engine real good (even under the engine cover)with a good soapy solution and rinse well, and the smell should go away.

[BOSS]

I had the same issue. At 160 miles, my car finally overheated, and it was due to a pinhole in the main Radiator hose, near the waterpump. The dealer couldn't even find it. They told me it was fine, and I had to explain that I saw it spraying out...they pressure checked that hose and found it faulty. I would bet money that is what it is...

[Swoop]

The thing that keeps sticking in my mind is that there was no smell until after their service work. I guess its quite possible that they strained an already weak hose and caused a leak. At what point could you see the spray of coolant? I've been over this engine with a fine tooth comb both when running and stopped, cold and hot and can't find anything. It kills me to take it back in again but its looking like the only solution, thanks to everyone for all the ideas.

[ffrcobra_65]

have ya looked for splash/stain marks on parts under the engine bay? A pin hole leak may not necessarily leak all the time, only when pressurized at high temps, and it would just squirt a very tiny stream onto the hot parts, not necesarily leave a puddle under the car.

[DS1937]

Put a pressure tester on the cooling system. Pump it up to about 15 PSI. If it holds pressure there are no leaks. Start it up with the tester on it and usually if a head gasket is leaking, the pressure will rise on the gauge. Also inspect the exhaust for excess steam, a leaking head gasket indicator. Don't forget to pressure test the radiator cap too.

[yota924x4]

yeah i have noticed the same thing, i had the heatercore tsb done about 3 weeks ago and i can still smell it. granted i have 30 some inches of snow and i've only put maybe 100 miles on it since then.

[2ndgenz28]

Should get a dye test done, they pour in some dye then use speical lights to find those hidden tricky leaks.