My 94, 3.0 auto has 179k on it and today I developed a coolant leak. I've had it almost a year with little issue, so I should have known my luck was running out. I was driving home and was less than a mile from the house and I heard a grind/clunk type sound. Not too loud, but enough to be alarming. I pulled over and started checking things out. Its been really slushy here, so I chocked it up to a chunk of ice coming off the wheel well. It wasn't.

When I pulled up, I noticed steam/smoke coming up from the hood near the firewall and the smell of coolant. The leak is ending up near the back of the trans. Not tons of coolant there, but its definitely noticeable. I topped off the coolant and ran it for a bit looking for the leak. Steam is rising from just to the passenger side of the exhaust crossover. The hoses look okay, no obvious signs of leaking. I was feeling the back of the engine and couldn't find a source of wetness. There is noise. My passenger described it as a grinding, gurgle or clunk under his feet? Its the same noise I heard earlier, but I'm having a hard time deciding how to describe it.

Could this be an external HG leak?
Here are things I do know:
The idle has been surging a little, even after warm up
My oil looks good, rad was just flushed (three weeks ago) and coolant looks new still
I have no white exhaust smoke and it smells fuel rich not really what I'd call sweet
It hasn't overheated, temp. hasn't left its usual middle mark

I'm probably thinking the worst, but I've been combing posts here for the last few hours reading everything I can about HGs and various coolant leaks. I plan on having the cooling system pressurized and tested at a shop on Wednesday. Any help on trying to narrow down the source would be appreciated. Thanks!

 

1. Remove the hood. 4 bolts & it's off (don't forget to remove the windshield washer hose!).

2. Check the little upside-down U-shaped hose that's slightly underneath the back of the plenum on the passenger side (coolant bypass hose). This is responsible for 90% of coolant leaks in that area.

3. If that's the issue, you can remove with a pair of LOOOONG handle needlenose pliers. I suggest replacing with OEM as other hoses will kink. They're not cheap, but if you aren't in a hurry, you can get cheaper from the link in my signature line. NAPA might have one, but I don't recall if it's a dealer item.

---Save yourself a LOT of trouble & take that hood off! It's so d@mn easy & will make the job TONS easier. So many ppl fail to do so because they think it will be a PITA, but it's not.

 

Would a hose leak create the noises I am hearing? Just curious? Going to pull the hood before it goes to the mechanic and climb up there.