2018 Mustang Ecoboost Blown Head Gasket?

[Bluelightning]

There is still pressure in the coolant when the engine is off. I shut the engine off and then opened the reservoir and you hear the pressure hiss out so it is possible that once I shut the engine off the residual pressure forces small amounts of coolant into the combustion chamber and then when I start it up the coolant gets burned up and sent through the exhaust.

Read what you just said.... If you scoped your cylinders you would have seen this coolant sitting on top of one of your pistons.... If you didn't see that then you don't have an issue.

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[ihasnostang]

Read what you just said.... If you scoped your cylinders you would have seen this coolant sitting on top of one of your pistons.... If you didn't see that then you don't have an issue.

+1 for scoping. taken with $30 scope https://www.amazon.com/dp/B077HLCLWH?ref_=ams_ad_dp_ttl

 

[BmacIL]

The coolant pressurizes due to the expansion of the fluid, which is due to the engine heating the fluid up (and therefore cooling the engine). When I shut the engine off, the pressure in the cylinders goes down, yet the pressure in the coolant fluid stays until the temperature of the coolant goes down, so how is it illogical to think that once the combustion chambers are not fully pressurized that the still-pressurized coolant will be able to seep into the chambers easier? I have no video of a warm, start but I don't think that I need one as that is not my concern. My concern is that the gasket is only a bit warped or broken allowing for that pressure in the coolant to seep through only a little over a long duration (like overnight)...

That's not how head studs work, dude. They are sized and torqued so that even during thermal expansion and contraction, there is sufficient clamping of the head gasket.

 

[Vicr]

You guys are drinking his Kool Aid. He's posted on the Eco forum also. Not as many biters there though...er drinkers.

 

[Adf020]

+1 for scoping. taken with $30 scope https://www.amazon.com/dp/B077HLCLWH?ref_=ams_ad_dp_ttl

This is not what I have, mine shoots 1080p and is much brighter

 

[Fatguy]

Yep, 5 pages and counting..

If you have a popped head gasket and coolant leaking into the cylinders, Condensation will start forming in the oil fill cap real quick and it will start looking like it's been drinking a milkshake ...

It is also possible to nick a head gasket and not leak coolant into the cylinders ,, it will pressurize the overflow tank, I had that happen once and only figured out it had happened after the pressure kept the thermostat from opening and the car ran hot.

.

A stupid, stupid f**kup at the dealer had them adding radiator fluid to my engine oil. I pull out and the engine temperatures soared. I shut it off and checked the oil and found malt. I freaked out and was heartbroken. They switched everything out and I was sure there was engine damage. That 5.0 V8 engine went 18 years and 375,000kms and was still running strong when I sold it to a Mustang restorer. This is also why I never go to a dealer for non-warranty work!


Next was a Corvette LT1 engine that always would show malt on the top of the dip stick and oil cover. It was never a problem and was like that for at least six years until I sold it to a mechanic.


This whole thread is much about nothing as far as I’m concerned. The guys with 2018 and up Coyotes have real reason to be paranoid though many live in denial. Go figure...

 

[NoVaGT]

 

[samanosuke47]

What a thread journey.

OP I don't believe you have a blown head gasket. Even a leaky head gasket, it just doesn't make sense to me, based on the evidence you've provided. Relax and have the dealer check it out.

I do think you're being very obsessive on it and possibly hoping for the negative? A bit trollish. Maybe you don't realize it.. maybe you do. Who knows. But relax.

And just to be a devils advocate, if that is 'smoke' and is a minor leak of some sort while the car is off and the engine is cold, I'm definitely quite certain it would get worse once the engine has warmed up and things are under pressure/moving about.

 

[TorqueMan]

The coolant pressurizes due to the expansion of the fluid, which is due to the engine heating the fluid up (and therefore cooling the engine). When I shut the engine off, the pressure in the cylinders goes down, yet the pressure in the coolant fluid stays until the temperature of the coolant goes down, so how is it illogical to think that once the combustion chambers are not fully pressurized that the still-pressurized coolant will be able to seep into the chambers easier? I have no video of a warm, start but I don't think that I need one as that is not my concern. My concern is that the gasket is only a bit warped or broken allowing for that pressure in the coolant to seep through only a little over a long duration (like overnight)...

The combustion chambers are much lower pressure than the cooling system during the exhaust stroke and under vacuum during the intake stroke (assuming you aren't into boost), so if you were getting coolant into your cylinders it would happen while the engine is running too. If the white stuff goes away after the exhaust system warms up then you probably don't have a blown head gasket.

Ambient temperature is a part of the reason you may see exhaust condensation at startup, the other is ambient humidity. Southern Texas can be quite soupy, but Northern Texas is generally drier, and you will often see condensation in the exhaust even when temps are up in the 60s. With higher humidity you generally need for temps to get lower before you start seeing exhaust condensation.

Here's the bottom line: If you DO have a head gasket leak it's clearly not big enough to contaminate the coolant enough to reduce its effectiveness or you would be seeing high engine temps. Same goes for your oil; if it were contaminated enough to reduce its effectiveness you would see a milky film/bubbles/froth/other contamination on the dipstick. What that means is even if you do have a blown head gasket you're not causing any engine damage at this point. If you can't drive it without obsessing until you know FOR SURE, then you'll have to take it to a technician that can diagnose it for you. It may be worth your money to take it to an independent shop (or two) BEFORE you take it to the dealer. You won't have to remove the tune or CAI if you take it to an independent shop for testing.

Personally, since you're not really hurting anything at this point, I would just keep driving it and monitor symptoms. You know what to look for, and I suspect you'll be checking obsessively. If you get more definitive symptoms then have it inspected. But for now I'd just drive and monitor.

 

[F1scamp]

I own a chemical tester like the one you used, I also run an automotive shop. The chemical tester is a great, quick test you can do to determine which direction you are going to go with further diagnosis. It is not an end all test, but a great first step. That being said, I have used it on probably close to a hundred vehicles throughout the years. Unless you are testing fresh antifreeze that hasnt been through the engine and gotten hot, there is always some sort of discoloration. Your resulting color is exactly what i would expect from a normal, run, cooling system.

 

[NoVaGT]

THEY SKY IS FALLING!!!!

 

[sZedely]

IIRC, that was because the wrong head-gaskets were installed on the wrong motors. I'm pretty certain they have that straightened out. And if there is an issue, just take it in for warranty repairs.

You area correct. This issue was addressed a while back.

Like NoVaGT stated, just remove the tune and you are good to go with warranty repair.

 

[PTM5.0]

Buddy if you popped a head gasket, you'd know it. YOU HAVEN'T. Take it from a guy who's been shoving too much nitrous/boost through high compression pump gas engines for a long time and has popped a lot of headgaskets pushing too far.
Here's how I know you haven't... 20+ psi is enough pressure that if your headgasket is leaking, you'd be pressurizing the coolant system and pushing coolant out the overflow tank vent. You would definitely smell it doing it also.

 

[ctandc72]

Buddy if you popped a head gasket, you'd know it. YOU HAVEN'T. Take it from a guy who's been shoving too much nitrous/boost through high compression pump gas engines for a long time and has popped a lot of headgaskets pushing too far.
Here's how I know you haven't... 20+ psi is enough pressure that if your headgasket is leaking, you'd be pressurizing the coolant system and pushing coolant out the overflow tank vent. You would definitely smell it doing it also.

The sweet smell of success...I remember those days. "Hey the new motor is ready, why don't we see how much nitrous the old motor will take before it blows?" I'm ashamed to admit I've done that.

 

[Bluelightning]

The sweet smell of success...I remember those days. "Hey the new motor is ready, why don't we see how much nitrous the old motor will take before it blows?" I'm ashamed to admit I've done that.

I'm not ashamed to say that I've done this..... Got to know how far you can push..

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