Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Likelihood of Honda Civic cracked engine blocks?

What percentage of 2006-8 Honda Civics develop a cracked engine block (aluminum)? I love my 2008 Honda, but reading about this possible defect worries me. Any preventive steps to take? Am I worrying needlessly? I miss the NPR Car Talk show!

Honda extended the warranty for as much as 8 years covering the coolant leak, so if you go to your local Honda dealer you could get the engine block or even the entire engine replaced free of charge (if you have a coolant leak).

There is nothing you can do, proactively to prevent it. Just keep an eye out for leaks. On Car, there were 48 cracked engine blocks of 596 complaints filed of about 400K cars sold. Pretty darn small!

I don’t think Honda even knows what PERCENTAGE have cracked engine blocks. As others point out, Hinda has been normally good at issuing extend warranties for covering manufacturing defects.

Do what you can to avoid the engine overheating experience. A single overheating experience can crack the block. Monitor the dashboard coolant temperature gauge, and if it ever behaves abnormally, even if it isn’t overheating, even if it is lower than normal, get the car to the shop. Put a mark on the gauge where the normal operating temperature is. Monitor the coolant level, and replace the coolant with Honda approved coolant every 2 years. If there’s ever any signs of coolant leaking, get that corrected right away. Make sure the engine compartment fans are turning on when they should and doing their thing. Does your car have an audio alarm if the coolant gets too hot? If so, and you hear an alarm, pull over and turn off the engine asap. If it is only a visual indicator for overheating, ask around if there’s a way to install an aftermarket audio alarm for coolant overheating. And if you get an overheating experience even after doing all this, don’t try to cool it off by pouring cold water on a hot engine. Just let it cool off by itself.

1 Like

I just bought a 2006 Civic 1.8l and was wondering the same thing. Honda sold over one million Civics in the affected years 2006 - 2008^ and there are 289 total complaints on carcomplaints, something like a .03% defect rate. Yes not every cracked block is being reported but it’s a big enough deal so that quite a few would be. But even if you said only 3% are being reported that’s still less than a 1% defect rate. And only 9 reports so far in 2018 so you get the feeling most of the weak blocks have already failed and been dealt with so your chances of getting a crack are pretty slim now over 10 years in.

At any rate after doing a little research I’m not that concerned. I still see a TON of 8th gen Civics rolling happily down the road every day so I’m guessing these cracked blocks are highly unusual and small in number. Most owners probably aren’t even aware there’s an issue. If Honda had to replace a million engine blocks they would go bankrupt and they seem to be doing just fine. Non-issue.

^Yes I know a handful of 2009 were included in the TSB. Only one complaint on carcomplaints so I left it out to keep from making the defect rate look even smaller.

my recently purchased 2008 honda civic was leaking coolant so i brought it to the dealership today. they diagnosed that the engine block is cracked and told me the warrantly expired 7 months ago. they’re gonna call honda hq and get back to me after new years but fixing it could cost several g’s. FML!!!

finally i got engine block crack on my Honda civic 2008 – with only 78k miles on it, local dealer quoted $3500 for the repair (replacing the engine)…Worked with honda over past 3 weeks, they were of no help, refused to do anything further. Given the age of the car only option for me is to scrap than spending 3500 on it,

Honda dont give any consideration of my long standing Honda loyalty (i owned 3 honda vehicles),and regular service history/oil changes etc… they just told this is outside of 10yr ext warranty…

Car was in very good running condition until this problem just popped up…Had spent almost 1200k on various recommended maintenance work in the past 1 year, hoping i could keep it for couple more years given the low mileage…no warnings, until one day coolant smell and overheating, stopped the vehicle, towed it to the dealer and just 3 weeks later I am looking for a scrap buyer… :frowning:

Anyone driving a Honda Civic out there from these defective VIN series, better get rid of your vehicle before this happens to you…while there are only a low % cars with these defects, it is not 100s but easily in many thousands… Honda conveniently will never disclose those numbers… They will not even respond to you in email or writing on these cases…

Most dealers i talked to in Houston areas have seen many cases of these, so nationwide you can guess how many could be there… I was thinking of low probability until this all happened. Don’t expect any sort of help from Honda as it is way past 10yr ext warranty…

I am pretty sure a 2008 Civic with only 78,000 miles is worth more than $3500 if the rest of the car is in decent condition. Also, I very seriously doubt you could buy a better, more reliable car for $3500 than what your Civic would be with a new/rebuilt engine. You should think carefully before sending this one to the junkyard!


Even with so few miles, I don’t expect any car company to warranty an 11 year old car.

What I wonder is why anyone would buy a used car without having it thoroughly checked by their mechanic, and doing research on known issues like this one.

If you aren’t prepared to do your homework before buying a used car, you might want to buy new. I know doing the research for known issues and getting a potential car checked by your mechanic at your cost can be a lot of work and a hassle, but you need to make the time if you’re going to continue to buy used cars.

Being a “certified used Honda” means almost nothing; it’s a marketing term. I’ve found issues with certified used cars that should have been spotted on even a cursory inspection, let alone a thorough one.

I don’t see any references in the above posts about “certified” Hondas or even that most of them were bought at Honda dealers.

People don’t get them checked out because nothing ever goes wrong with a Honda or Toyota…Right?

Bases on the statements about loyalty to the brand, I thought that might be relevant without it being mentioned.

I’ve repaired several of these engine block issues. Its a simple repair, but it does involve some minor wrenching. Since I go looking for instances that require wrenching, I dont mind this sort of thing. But I can understand other non mechanics reaction to something that sounds so ominous. The repair takes about 2 or 3 hours to perform, maybe longer because of meticulous prep, but…

Of the ones repaired in recent times (3 Honda’s 1 BMW, 2 Hyundai), none have had any issues further, its a shame this sort of thing happens, but…its more of a shame to give up on a very solid vehicle because the blocks develop hairline cracks in the water jacket on the front side of the engine (in Honda’s instance). The hairlines weep coolant, you just drain the coolant, rinse the block out with water, prep and clean the areas (important) and then choose the material you wish to use. No need for welding at all… Its the prep that matters most in these instances.

1 Like

What’s the price tag when you do that job?

Could the $3,500 cost listed above be a case of a mechanic thinking he has to replace the block or replace the engine?

It doesn’t take much overheating to warp the head on a Civic. It can happen even if the temperature gauge doesn’t go into the red.

What do you use as an alternative to welding?

i see an 08 motor w/80k miles is around $450 in my area. i found a clean 08 e250 van than that needs a trans and the trans are higher. $600-800-1000? who knew

May I assume you’ve seen the repaired blocks several times since the repairs with your own eyes and know the repairs have held up?

Have the repairs held up a few years, at least?

Compared to a generic “cracked block” label, this precise description is, could it be said, comforting. Or, are there other locations where cracks have developed on these engines - locations that are impractical to repair?

My $50 1979 Toyota 4X4 had a crack in the left side of the 20R engine. It weeped coolant. I carefully dremeled the crack’s surroundings and cleaned it meticulously, then applied JB Weld. It never leaked again in the years I drove that truck. A broken frame was its demise.

“Cracked block” sounds like it’s all over. Not always.

Which JB Weld product did you use? These days, JB Weld is a brand, not a product.

It was a 2-part epoxy/putty, gray in color when mixed. I have seen a fast-setting version since those days. I used the ordinary version. That was about 25 years ago.

Of all the blocks that I have attempted repairs, I know all have held up over 2 years and still going. One of the repairs I simply lost contact with because the fellow moved out of the area. The issues in the Civic are a relatively minor (if you can call a block crack of any type minor) hairline cracks in the area of the front of the block where it has the webbing cast into the sides. I guess the mold created thin areas here, and each Honda leaked in the same two places.

Here is a video of the same exact leaks (in the same exact places) encountered on a Civic. A thorough prep and epoxy is what has worked thus far. Of course the first one done was a Hail Mary, but it worked and I haven’t found need to go deeper than that… Yet.