5VZFE Issues

Hey Everyone!
I recently purchased my 2003 tundra at the start of 2020, and many things have been done and repaired on it. Things like a starter, new windshield, timing belt and tensioners, radiator, valve cover gaskets and VHT wrinkle paint (Much, much, much more but I digress)
The only recurring issue i cannot seem to figure out has to do with the exhaust.
Around 2-3 minutes after a cold start, the juncture between the end of header and the exhaust manifold begins to bubble and smoke. I learned later that it was oil, SUPPOSEDLY coming from the valve cover gaskets. After I changed virtually every gasket on the top of the motor (using Fel-Pro gaskets), the issue still remains. I thought it would disappear over time, but it still smokes and absolutely reeks of oil. I have also attached a picture with the trouble area circled.
Any ideas of what this could be, or what might need to be replaced?

 

I have a 5VZ-FE engine also. I haven't torn that far into the engine enough to be able to help you. I do know some people who may be able to help, or at least give advice.

@empty_lord

I've only replaced my injectors. Sorry that I'm not anymore help.

Regarding your gaskets, all the V8 folks swear by OEM. I'm not sure what Fel-pro is or if thats the OEM gasket people.

Edit: is possible its just the gasket for that exhaust union?

 

Did you replace the head plugs at the back of the engine? Can’t say I’ve ever seen a leak onto the exhaust like that

 

I would look again at the valve cover gaskets. My old T4R had the 5VZFE and on the 4runner forums I only saw problems when people changed them with anything other than OEM. The most likely culprit is probably the half moon plugs on the back. Did you replace those, did you clean the area well of old FIPG, and did you apply new FIPG correctly?

Keep us posted.

 

I know the V8 has two half moons on the back of each Valve Cover. I would have never known to break them off, clean, and re-seal them with the Toyota FIPG 103 Sealant. Not sure about the V6, though.

OEM Gaskets are best for the next go around if needed.

 

V6 has half moons and full moon seals. Since the v6 uses the same head on each side, the hole needs to be plugged where the cam comes out

 

I replaced the cam plugs when I did the valve cover gaskets about a week ago. This problem was there before and was thinking it was the rock-hard valve cover gaskets. The only thing is, nothing is leaking onto the manifold, it is leaking OUT of that juncture. (Strange.) I am going to look into the "half moon" plugs mentioned above (Thanks ), but I am considering the Doug Thorley Header/Manifold system. It's just strange having this engine in a Tundra, they're kinda rare.
UPDATE: Here's a video, I got youtube to work. https://youtu.be/9Eej7lqjTsI

 

Hey my 1st post to help - These engines aren't rare at all. I fixed my Toyota T100 with $388k miles a few months back... Never had this issue but I checked on the 4runner/Tacoma forums a lot to get my issue with this 5vz-fe engine fixed. So if in doubt with this engine check those forums. Btw by the looks of it I would also say its the half moons that may be leaking. Also there is a circular black plug back there as well that can be an issue as well.

I did my valve cover gaskets and although time consuming. It was not a hard job.

 

If I had to guess, I'd say the oil is leaking on the manifold when you shut the engine off, then seeping into the joint. Then when you start the engine, the oil that seeped in is being driven out by the pressure of the exhaust.

If you grab a clean paper towel and run it around the edge of the valve cover -- including the back, I bet you'll find your oil leak.

 

Thanks Everyone! I'm going to try some of these suggestions then check back.