what causes an exhaust manifold to crack? would it be something thats wrong with the car internally that causes it to crack? or just the general heating and cooling over time

 

is the manifold your talking about the ones on the dx models? thats a common problem most ek's with the stock manifold have over the years of use. my manifold on my hatch was cracked when i removed the heat shield. no need to worry.

srry if this doesnt answer your question.

 

how damaging is it to the engine to drive it with a cracked manifold?

 

After a while, you may kill your O2 sensor. That will cause it to run rich, which will eventually damage your cat and kill your spark plugs, which will hurt the performance of the engine. Running rich can also eventually "wash out" your cylinder walls, causing abnormal wear on the piston rings.

I've been driving my car with a cracked manifold for over a year; no idea exactly how long because my heat shield was covering it. It's cracked right between the runners, and into the O2 sensor bung. My check engine light just came on about 4-5 months ago; so at least 6 months after I noticed the crack.

You're pretty much guaranteed to fail emissions, because of the false readings it is going to give the O2 sensor.

 

You will also burn your exhaust valves there.

My dads car did, and its manifold was cracked between 2-3 and both cylinders had burned em up.

 

get a new one or buy an aftermarket one and eliminate the catalytic convertor thats what i did with my 97 ek hatch and used a o2 simulator to fool the ecu

 

hmmm im purchasing a car that has a cracked manifold, i need to take it home its about a 30 minute drive on the freeway, would you guys say its safe to do so?

 

just keep the window open so you get fresh air

exhaust fumes . . .

 

I would say it is safe. Honda still has the extended emissions warranty, up to 150,000 miles, if I remember correctly.

 

Its normal for a car that age to crack the exhuast manifold and not an indicator of other problems. There's bigtime thermal stresses in an exhaust manifold and it's made of shitty cast iron. Over time it cracks. Depending on how big the crack is there's either no effect or like everyone else said it will crap out your HO2S and screw up A/F ratio and all kinds of crap from there. But driving just long enough to get it home to fix it is nothing to worry about.

 

would jb weld be strong enough to patch it just for now? i used jb weld once before wasnt as strong as everyone made it out to be... :/

 

I doubt jb weld would do much of anything even in the short term, especially with the heat involved.

 

If I'm not mistaken, JB Weld isn't meant to deal with nearly that much heat, so it'd probably melt off or even catch fire.

 

Call honda it was a recall, they may still cover it, my friend got one, when his broke at around 170k, it may vary by dealer though.

 

interesting.. when I had my d16y7 I also noticed that I had a crack on the header.. this should have been a recall but us Hondaphiles just swap the motor and header anyways

 

Are you sure his car had 170k? I thought the limit for Honda/replacement was 150k??

 

I 'think' I'd have to call him and find out for sure. But that is likely why I put around. I don't know for sure.

Hell, I don't even know if he still has the car lol

But why did you bump over a year old thread?

 

Well mine just came up cracked recently & I was searching for related threads. Jeez this happens quite a lot I see! Just sucks big time for us Cali folks! I wish I could just do the EX swap stuff

 

yea, it is a pretty well known issue for these cars. Fortunately mine hasn't cracked yet

Why can't you swap to the Y8 stuff?

I would still talk to the dealer, and just see what they can do for you.

 

Can't do the Y8 stuff coz the Stupid California smog bullshit! Sometimes i wish i could just move to another state! Too much bullshit in Cali! As long as it burns clean thru the tail pipe is all what should matter... I'll try to talk to some dealers

 

So, you can't do the EX header swap and add the new catalytic converter and midpipe?

I did the same to mine years ago and it still passes inspection with flying colors

 

I always thought you could do it. Of course you'd have to swap everything over to a EX.

If aftermarket headers can pass why can't a OEM for a different car?

 

Hmm...I hadn't thought about it, but this might be what's going on with my '90 Accord. The manifold has a small crack, and that cylinder's exhaust valves are screwing up.