Oil in coolant is my head gasket blown?

Past week I've been hearing knocking when I start my truck and it immediately goes away withing a few seconds. Then yesterday I had a low oil light pop on so I checked the oil and was a bit low so I added 1 quart.

Today I started to over heat so I pulled over and saw my coolant filled with oil. There is no coolant in my oil so far as I can tell.

I'm pulling apart the engine and I see sticky almost gummy residue on the driver's bank of the intake manifold.

I had engine work done at 55k under warranty for a missfire on one of the cylinders but I'm at 100k now and they won't warranty it (even tho after they did the work my engine makes a funny vacuum noise at certain rpms).

My question is this most likely a blown head gasket or cracked? I'll attach as many pictures as I can.

Also when we compression tested it the driver's side all had significantly less compression compared to the passenger side.

Update here's what two of my pistons look like.

 

I'd try to run a borescope into the cylinders if you wanna know of the head's cracked or gasket compromised.

If that's the bank that was repaired then i'd honestly contact Toyota corporate and explain the situation see what they say, it's been a while so they could also turn you around and show you the door but it's worth a shot. Be cool, calm but know what you're saying on the phone to them

 

Thank you I have a borescope so I'll give that a go we did see the cylinder walls and they looked great but we'll get deeper in there.

Also I like the idea of contacting Toyota corporate just on the off change they will warranty the work done 45k miles ago it's definitely worth a shot thank you.

 

You'll have to pull it apart to see what's really going on. Head gasket is easy to fix, crack not at all.

 

You may also have to put a cooling system pressure tester on it to "make the leak appear"

 

I've been looking for some videos of other people doing it on a gen 3 but I haven't had any luck. I'm at the timing chain now doing more compression testing but would love some videos or forums for reference

 

Just hit YouTube & search for 2018 Tacoma engine rebuild. Should be plenty to choose from.

Good luck

 

Thanks I was searching head gasket replacement so I'll try that instead

 

Also should I pull out the oil cooler? Is it possible that that's what has failed?

 

I don't think it failed. You mentioned a rattle at startup, which is an indicator of the coolant in the cylinder.

 

It is possible but as mentioned above, rough running tends to be a sign that the combustion process is not right.

A failed oil cooler would only really allow mixing of the fluids, not so much a rough running condition except for *maybe* extreme situations. Especially seeing that you stated you have low compression on the left bank

 

Holy F.

 

I would take a look at the oil cooler. Usually oil in the coolant comes from something else. I have seen more coolant in the oil and steam from the exhaust when you blow a head gasket. Not to say that it can’t happen, just usually see it the other way around. Also you could use a combustion tester to see if you are getting combustion gases in the cooling system.

 

Your telling me lol I'm in touch with corporate and the local dealership so hopefully they'll help cover it

 

People --

The OP is at 100K miles, which is 40k miles outside any benevolent warranty window. FORTY THOUSAND MILES.

An ordinary misfire repair at 55k miles is exactly that - an ordinary misfire. Plugs are recommended to be changed at 60k miles so that could have been nothing more than a slightly prematurely worn spark plug. That does not entitle anyone to a free engine forever.

OP has also described on a public forum about hearing knocking on start-up but continuing to drive the vehicle. No, no, a thousand times no.

Toyota has zero moral and certainly zero legal obligation whatsoever to fix anything considering such absurd circumstances.

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Continue to pull it apart.
Diagnose it correctly and repair it.

I would suggest, at a minimum, you should replace both head gaskets and the timing chain set. At a minimum. You might also wish to look at your water and oil pumps and have your cylinder heads sent out.

Frankly, by this cost point, depending on your compression test results a re-manufactured engine may be more cost effective.

I disdain being a buzzkill. But I'm not sugar-coating anything either.

 

You should get some more information about the cause of the misfires on tacoma 2gr-fks engine. It is not a spark plugs.
And the cost of the repair is less then used engine.
Toyota's head is about 1k if warped.
Machine shop can do head checking, cleaning and swap valves for $200-300.
You can buy a head gasket kit from Toyota that includes every gasket and o-rings.

 

After calling Toyota for fun, I agree with pulling it apart for further inspection and diag if you don't see the issue with a borescope.

Where i'll deviate from agreeing is that if the head is cracked or warped, I would just replace it instead of machining it. Between finding a good machine shop that has experience working with this engine, the possibility of persistent timing codes due to the machining. Especially if they machine one head more than the other is a risk don't think is worth it.

Scan it for codes and see what you have. It's possible the knocking is from a vvt gear and the coolant issue is just a head gasket.

If it comes to it, I would get a scrapyard engine instead of a remanufactured engine... remanufactured engines(and most all other parts) from what i've seen are often a gamble and not the highest caliber reman job as a guy would expect from such companies

 

If the oil cooler leaks, the main symptom is oil in the coolant. This can cause many people to think that the head gasket is blown. However, a blown head gasket usually affects the engine's performance. If the oil cooler leaks, the engine will still perform normally.

 

Here's my pistons on the side that Toyota changed also I have more info on their work I'll attach that soon

 

interesting, what engine work did you have at 55k?