2003 Corolla oil leak

[DogLover]

My wife has a 2003 Toyota Corolla with 128,000 miles. We bought the car with 90,000 miles and I have changed the oil every 5,000 mile using conventional oil. Oil has been whatever name brand was on sale. The engine is a 1.8 litre I4, code 1ZZ-FE. For about the last six months the car has leaked oil. The leak seems to come from the top of the engine, in the back, on the passenger side. I can't tell exactly where it is coming from. My question is, are there any common places on this model engine that are prone to spring a leak? The leak is not terrible, just a few drops each time it is parked. But the engine has quite a bit on it. My guess is either the crankshaft seal or timing cover gasket but this is only a guess.
Thanks,
Terry

 

[Barkleymut]

no idea as I have never owned a Toyota. But try some Maxlife on your next oil change and see if it works. It made my wifes van go from a pretty bad leaker to no leak at all in a few hundred miles.

 

[DogLover]

Is the Maxlife high mileage oil? What weight oil did you use? The Corolla calls for 5W30.
Terry

 

[bigjl]

There is a 5w30 weight in Maxlife.

Maxlife Diesel 10w40 certainly dried up the leaks on my Taxi.

 

[FoxS]

You should go with the 5w30

Let us know if the oil goes black quickly. Another member used Valvoline High Mileage for the first time after using mainly high quality syns for high mileage and the High Mileage oil went black quicker than normal. He thinks its the seals.

What was the service history of yours before you got it? What does the engine look like down the fill hole. What is your wife's driving style / pattern?

 

[Trav]

This engine has valve cover gasket up top with no cam seals, that would be where i look first. Try tightening the bolts a little before changing the gasket.

Other than that you will need to clean the engine well and look for the leak, a dye and black light can help.

 

[Barkleymut]

Yes, try the 5-30 Maxlife. There is a very good chance it will greatly reduce or eliminate the leak.

 

[DogLover]

The guy I bought it from assured me the car had "regular maintenance". But I really have no idea how the car was cared for. My wife drives 80 miles to work Monday through Friday, at highway speeds. Not much in town driving. Down the filler hole is hard to see due to a baffle, but as near as I can tell the engine is clean. I do not need to add oil between oil changes at 5000 miles.

 

[friendly_jacek]

Originally Posted By: terry274
My guess is either the crankshaft seal or timing cover gasket but this is only a guess.
Thanks,
Terry


I've seen rare complaints about timing cover leaks in this engine on corolland.com forum. I also have 03 corolla and love it.

 

[Donald]

Cars do develop oil leaks. I would not blame prior owner. I would replace the valve cover gasket and see where it goes. You can try torquing it and see if that helps.

I would replace the easy gaskets before I used a High Mileage oil.

 

[Trav]

Originally Posted By: Trav
This engine has valve cover gasket up top with no cam seals, that would be where i look first. Try tightening the bolts a little before changing the gasket.

Other than that you will need to clean the engine well and look for the leak, a dye and black light can help.

To late to edit but if you look around the valve cover gasket and its damp or wet thats a good sigh its the valve cover leaking and you should try to tighten the bolts before changing the gasket.

Personally i stay away from seal swellers if at all possible with a cheap and easy fix.

 

[HerrStig]

Check out the Toyota Nation board, they have a forum specifically for Corolla, by year. You can search "oil leak" for DIY's.

 

[LeakySeals]

Hello,
The valve cover gasket and the Oil Control Valve for the vvt-i system are common leak points for the 1zz-fe. The OCV is located rear left passenger side.

As Trav stated, tighten both of them. Then replace the gaskets if necessary. Both are easy fixes on that engine.

 

[Astro14]

Originally Posted By: Trav
This engine has valve cover gasket up top with no cam seals, that would be where i look first. Try tightening the bolts a little before changing the gasket.

Other than that you will need to clean the engine well and look for the leak, a dye and black light can help.


This.

The mechanical answer (tighten or replace VC gasket) is far more likely to be successful than the chemical answer (High Mileage oil). There aren't too many places that this engine will leak...

 

[DogLover]

Well, it does not appear to be the valve cover gasket or the oil control valve.

I believe the leak is coming from the timing chain tensioner.
I couldn't get a picture of the chain tensioner, but it is surrounded by oil.

 

[LeakySeals]

Yep, thats another common place to leak. The timing chain tensioner is hydraulic, relies on oil pressure. So there is a fair amount of oil pressure in that area. There is a rubber o-ring gasket on the tensioner that hardens/shrinks from heat over time. Any issue with that o-ring, the oil will squeeze out under pressure. Its not that expensive, I would replace the entire tensioner. Worth it in the long run, the tensioners clog and lose function over the miles resulting in chain rattles at idle. You can get that out of the way while fixing the leak.

Or..as others have stated a High Mileage oil may swell that ring and you can forget about fixing it.

 

[DogLover]

My choices on the timing chain tensioner seem to be either Cloyes or Dorman. Any comments on these brands (from Rockauto). Would it be best to get the part from the Toyota dealer?

 

[Trav]

Originally Posted By: terry274
My choices on the timing chain tensioner seem to be either Cloyes or Dorman. Any comments on these brands (from Rockauto). Would it be best to get the part from the Toyota dealer?

Cloyes were good product but i dont know how they are today. Dorman is iffy stuff possibly of Chinese origin.

Something like this unless you know for a fact that the company made the OEM part eg NTN then go OEM.

 

[Quest]

I wouldn't go cheep on engine replacement parts (incl. water pumps, chain, chain tensioner, etc.) but to go with factory genuine parts.

Aftermarket parts are littered with garbage that will fail on you when you least expected: stranded on highway, or serious damage to your engine , etc.

Anyways, it's your money and it's your call.

Q.

 

[LeakySeals]

Yeah, for the tensioner I'd probably go OE its not that expensive. Trav, I've been using black or gray permatex at the end behind the o-ring to get a better seal. Not sure thats the right thing to do?