Start with replacing the o-ring for the timing chain tensioner. No need to replace the tensioner itself, but rather just the o-ring. It's cheap and easy. Here is a DIY on how to do it:

DIY 2003-2008 Corolla, Matrix, Pontiac Vibe 1ZZFE Timing...

I finally got around to doing a timing chain tensioner DIY for the 1ZZFE thanks to a leak on my 2003 Corolla LE. The leak depicted is after cleaning it about a month ago. This DIY will apply universally to all 1999-2008 Corolla, Matrix, Chevrolet Prizm, and Pontiac Vibe and should be very...

www.toyotanation.com

Fun Tip: The bore into which the timing chain tensioner inserts MUST be 100% clean of any varnish and/or debris. Use a solvent, like acetone, and a round brush, like this:

Fun Tip #2: Put some lube on the new o-ring before inserting the tensioner into the clean bore.

Fun Tip #3: Do not use any RTV/FIPG on the flange of the TC tensioner. The o-ring is what seals it, not anything else.

If you still have the leak after doing this, it might be the valve cover gasket or the timing cover gasket.

Here's a DIY for the valve cover gasket and also a DIY for the TC reseal:

https://www.toyotanation.com/forum/showthread.php?t=955337

DIY: 2003-2008 Corolla, Matrix, Pontiac Vibe 1ZZFE...

I recently purchased a 2005 Corolla for a family member. During inspection, I found the timing cover to be seeping from the cyl head-to-timing cover T-Joint. I decided to do a DIY guide to help others who are also experiencing this issue. Required Parts: Qty: 2, #90210-06013 (VC Bolt Seal)...

www.toyotanation.com

 

Start with replacing the o-ring for the timing chain tensioner. No need to replace the tensioner itself, but rather just the o-ring. It's cheap and easy. Here is a DIY on how to do it:

DIY 2003-2008 Corolla, Matrix, Pontiac Vibe 1ZZFE Timing...

I finally got around to doing a timing chain tensioner DIY for the 1ZZFE thanks to a leak on my 2003 Corolla LE. The leak depicted is after cleaning it about a month ago. This DIY will apply universally to all 1999-2008 Corolla, Matrix, Chevrolet Prizm, and Pontiac Vibe and should be very...

www.toyotanation.com

Fun Tip: The bore into which the timing chain tensioner inserts MUST be 100% clean of any varnish and/or debris. Use a solvent, like acetone, and a round brush, like this:

View attachment 462941

Fun Tip #2: Put some lube on the new o-ring before inserting the tensioner into the clean bore.

Fun Tip #3: Do not use any RTV/FIPG on the flange of the TC tensioner. The o-ring is what seals it, not anything else.

If you still have the leak after doing this, it might be the valve cover gasket or the timing cover gasket.

Here's a DIY for the valve cover gasket and also a DIY for the TC reseal:

https://www.toyotanation.com/forum/showthread.php?t=955337

DIY: 2003-2008 Corolla, Matrix, Pontiac Vibe 1ZZFE...

I recently purchased a 2005 Corolla for a family member. During inspection, I found the timing cover to be seeping from the cyl head-to-timing cover T-Joint. I decided to do a DIY guide to help others who are also experiencing this issue. Required Parts: Qty: 2, #90210-06013 (VC Bolt Seal)...

www.toyotanation.com

I read the guide for timing cover reseal. Do I have to continue to support the engine with a floor jack when the side engine mount is removed? Should FIPG also be applied to the engine side where the head meets the block?

How did you clean the cover and engine side? The guide states to spray gasket remover on the engine side, but should that be avoided to not contaminate the timing chain and other internal parts? Razor blade and then spray it down with brake cleaner? Should I avoid using metal wire brush?

Cleaned up the leak today. Here's some pictures after a few hours. Tensioner is leaking for sure. But it also looks like there's a small leak coming from the seam between the head and block.

EDIT:
Cleaned up the oil and drove the car for 10 min and inspected it. It does leak from the seam next to the tensioner.

I also noticed old oil gunk on timing cover where all the pulleys are located. Is this just a leak from the tensioner?

I can see that there's old oil build up next to the tensioner on the top left front of the timing cover. Not sure if it went down towards the crankshaft.

I can't get a good picture of it but there's a lot of old oil gunk at the area I marked with a red circle between the belt tensioner and to the left of the crank pulley. It's also slightly above so maybe oil from TC tensioner? Picture underneath the crank pulley shows no oil.

Should I be careful when removing the crank shaft pulley to not mess up the timings, if I were to attempt to reseal the timing cover? Any tool that should be used to hold the pulley in place when removing/installing the bolt? I guess I want to prevent it from rotating?