Bad Head Gasket?

[NWA_Dave]

I've read a few posts on here about the 3rd gen head gaskets, and it seems pretty common that the P0300 P0306 error is often a head gasket issue on the #6 cylinder.

Mine started running rough and the engine light was at first coming on intermittently (not blinking), then it was on and stayed on. I checked the codes and it was showing P0300 & P0306. There was also a small puddle of antifreeze just below the top radiator hose, on the timing belt cover. What I assumed happened was the leaky head gasket overpressurized the cooling system, forcing out some antifreeze where the top hose connects to the block.

After reading on here, it sounded like & seemed like the head gasket was the likely culprit. I purchased a bottle of the BlueDevil Pour & Go, followed the directions and let it idle for an hour.

The pour & go apparently did not fix the issue, as it's still running rough. However, there was not any more leaked antifreeze visible anywhere. I had only driven it around the block after using the BlueDevil.

I don't want to blindly replace parts, spending $ I don't have, and I can't afford to have the head gasket replaced.

Is there any way to test/know for sure whether it's the head gasket, without doing a compression test or anything else that requires paying someone or having specialized tools?

 

[phattyduck]

A couple of non-definitive things you can do:

- Start the truck (cold) with the radiator cap off, check for bubbles
- Start the truck (cold) with the radiator cap on, check for fast building pressure in the cooling system.
- Pull the plugs and check the condition of each
- Watch coolant levels carefully

-Charlie

 

[T4topher]

A couple of non-definitive things you can do:

- Start the truck (cold) with the radiator cap off, check for bubbles
- Start the truck (cold) with the radiator cap on, check for fast building pressure in the cooling system.
- Pull the plugs and check the condition of each
- Watch coolant levels carefully

-Charlie

Another thing I’ve read is check for white smoke at the exhaust, if you know how coolant smells when it’s burning/evaporating then you might be able to faintly smell it at the exhaust pipe as well.. blue smoke would indicate burning oil.

 

[SilverRidgeRunner1]

The best thing I've use to find a exact answer to your problem is use UView Combustion Leak Tester which will indicate exhaust gas in the coolant

 

[NWA_Dave]

A couple of non-definitive things you can do:

- Start the truck (cold) with the radiator cap off, check for bubbles
- Start the truck (cold) with the radiator cap on, check for fast building pressure in the cooling system.
- Pull the plugs and check the condition of each
- Watch coolant levels carefully

-Charlie

Okay, so I started with the truck cold. Removed the radiator cap, started it, let it run a few minutes...no bubbles.

Shut it off, replaced the cap, started it up again. Let it run a few minutes. Tried squeezing the top rad hose while it was running, could barely squeeze the hose and just a little.

Notes: No smoke, just a little bit of steam until it warmed up (outside air temp was 45 degrees). After about 10 minutes, the inside of the tailpipe was also dry.

While it was sitting there idling roughly, I pulled the #6 plug wire which made no difference at all. Now, I know that means I probably have a bad plug wire or coil, but what I don't understand is that if I never had a bad head gasket then what's causing/caused the excess coolant pressure and thus the puddle of coolant on the top of the timing belt cover?

 

[Clumsy me]

I hope you guys can help me out as well as I believe I may have blown my head gasket the other day.

I have a gen 1 supercharger on the truck for roughly 5k miles 190k total.

on saturday the truck drove fine no issues. Sunday morning it was rather cold out and raining all night and when I started it there was a bunch of white smoke, didnt think too much and drove off. When I got to my buddy's house I pulled in the drive way and noticed a rough idle, no drop in RPM just a lot of vibrations and there was still some white smoke out of the tailpipe.

A few hours later I went to leave and the truck started fine and didnt have a rough idle and very faint white smoke. The truck drove totally fine all the home and didnt have rough idle when I parked back home. I checked the coolant and I had lost about a 1/2 inch in the tank. Check back a while later and it was still low.

The truck has never overheated the whole time I have had it.

Am I in store for a head gasket job and a T Belt job? is it even worth it?

 

[Mudeprived]

Okay, so I started with the truck cold. Removed the radiator cap, started it, let it run a few minutes...no bubbles.

Shut it off, replaced the cap, started it up again. Let it run a few minutes. Tried squeezing the top rad hose while it was running, could barely squeeze the hose and just a little.

Notes: No smoke, just a little bit of steam until it warmed up (outside air temp was 45 degrees). After about 10 minutes, the inside of the tailpipe was also dry.

While it was sitting there idling roughly, I pulled the #6 plug wire which made no difference at all. Now, I know that means I probably have a bad plug wire or coil, but what I don't understand is that if I never had a bad head gasket then what's causing/caused the excess coolant pressure and thus the puddle of coolant on the top of the timing belt cover?

A block tester is a nice tool to have. Might wanna pick one up.

My upper hose was leaking in the same spot. It was due to the hose being old.

Pull the plug and inspect.

 

[97t4r81]

Okay, so I started with the truck cold. Removed the radiator cap, started it, let it run a few minutes...no bubbles.

Shut it off, replaced the cap, started it up again. Let it run a few minutes. Tried squeezing the top rad hose while it was running, could barely squeeze the hose and just a little.

Notes: No smoke, just a little bit of steam until it warmed up (outside air temp was 45 degrees). After about 10 minutes, the inside of the tailpipe was also dry.

While it was sitting there idling roughly, I pulled the #6 plug wire which made no difference at all. Now, I know that means I probably have a bad plug wire or coil, but what I don't understand is that if I never had a bad head gasket then what's causing/caused the excess coolant pressure and thus the puddle of coolant on the top of the timing belt cover?

The iac/tb have coolest lines to them, check there.

 

[thegipper]

Long story short.

I suspected my 97 had a bad head gasket (slowly loosing coolant but couldn't find any leaks). I inspected the plugs, bore scoped the cylinders, used one of those dye test kits (worthless), watched for bubbles in the radiator/reservoir, smelled for fuel in the coolant, checked the oil and so on and none of these attempts gave me ANY solid answer.

Then, I did the a leak down test. Once I pressurized cylinder #3, bubbles came out of the radiator.

I 100% knew at that point, I did in fact have a blown head gasket.

The leak down test is the gold standard for diagnosing overall engine health.

 

[phattyduck]

Okay, so I started with the truck cold. Removed the radiator cap, started it, let it run a few minutes...no bubbles.

Shut it off, replaced the cap, started it up again. Let it run a few minutes. Tried squeezing the top rad hose while it was running, could barely squeeze the hose and just a little.

If the head gasket was leaking, it would be less than a minute to a full-pressure cooling system. If you let it idle for a few minutes, it would be warm enough to pressurize the system normally (12-15psi, which will make the hoses stiff).

The leak from the top hose could just be a leak! Make sure the hose and clamps are in good shape, that there isn't build-up on the water outlet neck, etc.

If the plugs and wires are old, it would be worth changing those. Also get a new OEM radiator cap.

-Charlie