Best way to check for head gasket failure?

I've read about various methods: radiator hose disconnect, whooshing sounds under dash, coolant/oil mixed, compression test, leak-down test, etc.
I think my HG may have a leak. This is my daily driver and am looking to confirm my suspicions as quickly and cheaply as possible and start ordering parts. I think I may have just a small leak so I'm not confident the normal tests will really show anything based off what I've read on here.

 

You just listed the most common ways to check. What is making you think you have a problem?

 

Cylinder 4 misfire codes, truck is at 139k miles

 

coolant in the oil, open radiator cap or over flow bottle start truck and see if you have any bubbles in it, see of any antifreeze is leaking between block and heads.

 

haven't seen any coolant in the oil, but I'm not 100%. No bubbles that I can see. Would it bubble at every start-up or only on the times where I have a rough start? No leaks around the block I've found.

 

So which way of checking should I use? One or all? Some have posted clear results on the various tests and it still ended up being the HG.

 

compression test is the best way, sometimes head gaskets blow between cylinders or into exhaust.

 

@Gear Head have any suggestions?

 

Agreed, compression and leak down tests are the only ways. Looking for fluids mixing, bubbles, etc. are quick checks but nothing conclusive.

 

You can have the coolant checked for hydrocarbons.

Sometimes, while watching inside the overflow reservoir, bubbles won't be there, until the engine is at full operating tempurature.

Spark plug with coolant on the tip is an indicator of a leak.

 

Did you overheat? A cylinder misfire could be something super simple. Bad fuel, bad spark plugs, injector. Your head gasket usually won't go unless you ran it hot.

 

Makes sense, basically what I suspected

 

What's more conclusive for a small leak, the leak down or compression test?

 

Is that because the thermostat isn't open when cold? I checked last night, no bubbles when engine was hot. No fluid on the plug either

 

No overheating. Changed coil and spark plug on cylinder with no change. Ran fuel injector cleaner through with no change, although I could suppose I could switch injectors from cylinder to cylinder to see if problem follows

 

Thanks for all the tips so far, still getting cylinder 4 misfire and last night it had a pending code for P0430 (cat, bank 2) but that might have been just been the fuel injector cleaner running through...

 

05s had some issues with blown head gaskets. Toyota changed the head gasket design to fix the problem.

 

That's why I highly suspect that my truck has a leaky HG. I'm trying not to draw out the testing process, if I need to jump in and do the head gasket I want to start ordering parts and get to it. Compression test is next, i'm just worried the leak will be too small and since the problem is intermittent maybe it will not register on the compression test

 

If the coolant tastes like Mountain Dew there is a leak, if it has a taste like Dr. Pepper 23 flavors you're in the clear.

 

Let me ask this. Have you sprayed around your engine bay, with something flammable? Silicone, brake clean, starter fluid, etc?

What if your misfire is because you have cracked vacuum hoses? Yours is an '05. Miles and age wears down rubber hoses.

Check them. You can even listen for a hissing noise. If you spray, and your idle changes, boom. Vacuum leak.