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Hi I have an 03 civic. Engine is the 1.7. I noticed a couple days ago that my car developed a loud exhaust leak that sounded like it was coming from under the hood so I opened the hood and saw a missing bolt to the manifold I believe. Can anyone tell me the part Number for this bolt and if it’s a hard fix? Looks like it might just screw in?
thanks
You might wanna pull the manifold and make sure it's not snapped off in there. Those don't really come out on their own, and judging by the amount of rust on that heat shield, it'd be worth a look.
As far as part number, any M8-1.25x20mm bolt you can pick up at an auto parts store will do (actual OEM size is M8-1.25x22). If you're adamant about getting a brand new OEM bolt, the part number is 90003-PLC-000. Dealership will probably charge you $4-5 each.. Or you can pick up a 3 pack of M8-1.25x20 bolts at Autozone for a few bucks. Make sure you get a grade 8 or better flanged bolt that looks like this (color doesn't matter):
A pack of 4 of these m8-1.25x20 (grade 10.9) at O'Reilly Auto is $4.29
Thanks for the quick reply. Would I be able to see it if I took it off? Would the bolt in the engine be causing a noise I could hear? Right now it just sounds loud like there’s a hole in the muffler or something. I don’t hear any rattling or anything. Thanks for the info on the bolts I’ll stop at oreillys tomorrow after work.
that is your heat shield. Exhaust is under it, so that bolt does not have any relation with open exhaust type issues.
you need to remove the shield to see the exhaust
After doing more research I noticed it was holding the heat shield. Is that all it does? Not heat shield and manifold? I had my boss look at it while I revved the engine and he said he saw exhaust coming out of that hole but for all we know it could be cracked underneath the heat shield and coming from there. I’m going to look more into it today since I got rained out from work. Is the heat shield just those two bolts? The one I’m missing and the one to the left of it?
Thanks!
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Re: Manifold bolt
Originally Posted by Silentbob6
After doing more research I noticed it was holding the heat shield. Is that all it does? Not heat shield and manifold? I had my boss look at it while I revved the engine and he said he saw exhaust coming out of that hole but for all we know it could be cracked underneath the heat shield and coming from there. I’m going to look more into it today since I got rained out from work. Is the heat shield just those two bolts? The one I’m missing and the one to the left of it?
Thanks!
There's some lower ones as well, they may not come out nicely
Got a chance to look at it today. Removed the heat shield and started the car and I don’t see any leaks anywhere. The exhaust, while rusty, doesn’t have any holes that I could see and seemed pretty sturdy while I was shaking it underneath the car. It sounds like it is coming from that manifold but I didn’t see anything wrong with it. I was gonna remove the manifold but with my luck, I wouldn’t be able to get it back on and I need the car for work tomorrow. I took a couple videos for you guys to hear the sound. Maybe it’s not even an exhaust leak
Thanks!
he has a lot more recent experience with a D17. I haven't messed with a D17 since October 2017. Haven't messed with a stock exhaust manifold since 2004
