Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Cracked block: 2003 Toyota Corolla

My wife bought a 2003 Toyota Corolla with 70k mi one year ago. After driving it an easy 10k more miles (to and from work in Los Angeles) the check engine light came on. She took it to a mechanic, who found a crack in the engine block.

Two questions: 1) is it not crazy for a problem like this to happen, especially driving short distances in mild weather? The mechanic felt like this was the result of a factory defect in the casting, but Toyota is unwilling to do anything 2) Other than Bar’s, is there any moderate cost solution that does not entail replacing the block? Thanks for your help!

This is so highly rare on a stock engine, and so bizarre a diagnosis for a check engine light, that I’d definnitely get a second opinion.

If the engine block is cracked, a whole hell of a lot more would have happened besides the Check Engine light. There would have been horrible noises from the engine along with overheating. If none of this occured, you might want to get a second opinion as to why the Check Engine light came on.


C’mon . . .you know the answer . . . a crack in the block will eventually cause the whole engine to fail. I’d look for a used engine, putting all of the good stuff from your 80k mile engine on the used engine. Is it crazy for this to happen? No . . it’s a machine and machines break. Use Bar’s ? Don’t bother . . . you’ll be stranded somewhere on the freeway some inconvenient dark and lonely night. Replace the engine, you’ll have spare parts for the engine for years or you can part the stuff out for $$$ to other needy Corolla owners. Good luck. Rocketman

Like mountainbike, I would tend to doubt the diagnosis given by your mechanic.
Did the mechanic offer to take the car off of your hands, by any chance?

Have a second mechanic or shop look at it… Have them SHOW YOU the crack. If the block IS cracked, shop around for a used (salvage) engine. Google “used Japanese engines”.

Since the odds of a cracked block are extremely slim you should get another opinion.

What are the symptoms? Any noise, poor running, oil or coolant leaks, etc.?

There aren’t a whole lot of other symptoms. The car leaked coolant, but seems to be retaining the new coolant I put in. No horrible noises or overheating. The car runs and sounds friggen fine, despite the fact that it apparently needs a new engine…

Took it to a Toyota dealership and they confirmed the crack that my independent mechanic found.

I had a 327 Chevy with a cracked block. It was in a strange place and leaked a little coolant out of the side (probably a defect).

Usually, though, if the block is cracked, you will have a whole lot of problems. Often, you will find a bit of oil floating in the coolant (pop the cap off and see if you see beads of oil floating on top) or coolant in the oil (check the dipstick, you may find foam in it). Sometimes, enough coolant will leak into the motor that your car will burn it (or at least turn it to steam). Your car will emit white “smoke” when it warms up.

As far as a repair, look for a vehicle that was smashed in the back and totalled. A lot of times, you can pick up a junked car and get an entire drivetrain for the price you would pay to get a new block.

Sometimes you can get away with just driving it too. I drove the 327 for another 65K miles before I took it out.

I sealed a cracked block using K & W seal. The car was a 1947 Pontiac that I bought for $75. I started getting coolant in the oil and after removing the cylinder head (easy to do with a side valve engine), I found a crack around a valve seat. The car was still running and no coolant getting into the oil a year later when I bought a better car. If the block is truly cracked, you might try this repair while you search for a good used engine.

It is entirely possible that a lower mileage engine like yours develops a crack in the block.
Not all engines from the same engine line are perfect, you know.

Now, the first thing you should consider is where the location of the crack is on the block.
Is it in the cylinder head, or is it actually in the engine block?
Is it in a coolant passage that leaks internally into the engine oil pan, into the combustion chamber, or does it leak externally to the outside air?

If it is an external leak, I would recommend having the engine inspected by a shop proficient in welding engines, to see if them might be able to drill two small holes at each end of the crack (this prevents further spreading of the current crack), and then weld up the entire current crack to seal it, and prevent further cracks in the same area.

If it is an internal coolant leak in the combustion chamber, the block is hosed, and needs to be replaced.

If it is an internal leak in the coolant jacket that is outside of the combustion chamber, then you can perform the same welding process mentioned previously in.

Same applies for the cylinder head.
If the coolant leak is into the combustion chamber, then replace the head.
If it is external, weld it up.

Get this done soon, before the engine is damaged.
It is possible to get another engine for less money from a salvage yard. Research this possibility.


2nd opinion is in order.