Highly Pressurized Valve Cover on 2007 2.4 Toyota DVT-i?
Hi Scotty long time shade tree mechanic subscriber here. Thanks for all your helpful videos!
My brother-in-law has a 2007 Toyota 2.4 DVT-i 16 valve motor made in Japan. It uses no oil or antifreeze and the car runs fine. He lives in Florida and I am trying to help him diagnose the issue from Kentucky.
The motor was rebuilt by a Toyota dealer about 40,000 miles ago under warranty 6 or 7 years ago. The car had about 30,000 miles on it when it had a head gasket leak into the oil which wiped out the rotating assembly. My guess is that it’s the original head, new cams and valves.

He recently noticed that when he removes the oil filler cap from the valve cover while the motor is running there is a lot of air pressure escaping from the inside of the valve cover. A LOT!
I had him place his hand on the exhaust pipe to feel the pressure and rhythm of the exhaust. Then I had him compare that to the rhythm of the pressure coming from the valve cover oil filler opening. He said the pulses and frequency coming from the filler area felt the same.
I’m concerned it’s exhaust valve seals or cracked cylinder head leak. That might somehow explain no oil or antifreeze usage.
Is the highly pressurized valve cover a normal part of the EGR system on a Toyota or is this unusual?
If unusual can you point us to the most likely cause of this issue?
Thanks again from your long time subscriber, Bob in Kentucky!