I want to remove the Air Box from a Honda Civic EX 2014.

  1. What is the bolt type or code?
  2. What is the socket do I need?

enter image description here

  • Honda uses JIS bolt head sizes, so its a 10mm, 12mm, 14mm,17mm. My guess it is a 12mm head bolt.
    – Moab
    Commented May 4, 2020 at 21:02

2 Answers 2


Most often Metric sockets are used in the range of 8mm to 10mm for most components in the Honda small cars. I have found using 1/4-inch drive socket sets makes things a bit more accessible. Many times, a longer 8-to-10-inch extension can work into the tightest spaces. Keep in mind very tight bolts in the engine compartment are not uncommon and using 6-point sockets in these cases is better than a 12 point to avoid rounding of the heads. Flex head ratcheting wrenches can be your best friend as well on small cars and I search out fine tooth versions for those times you can't move more than an inch at a time! My own car is a Honda Fit sport and I'm no stranger to the engine compartment.

  • Welcome to Motor Vehicle Maintenance & Repair! Would you please take a look at the Help Center so as to tell what we're actually looking for concerning answers. I'm seeing a trend with your "answers" which is, they don't really answer the specific question. More so, it looks as though you're trying to provide information on questions which have been answered a long time ago with a selected answer already in the thread. Not that there is anything inherently wrong with that, however, your answers are either incorrect or of very poor quality. Commented Jan 22, 2023 at 16:18

Not sure why you'd be interested in the type of bolt ... as in, why does it matter? Sorry, I'm not trying to be flippant about it, it's just an odd question. It's a bolt with a large flange on its head. It passes through a rubber grommet, which is why it has the large flange on it. It doesn't require a special socket, if that's what you're worried about?

As for the size, I don't have direct knowledge of it, however, as Moab alluded to in the comments, it's most likely a 10mm. The old adage of Honda putting their cars together with 10mm bolts only is not far off the mark. Other Civics I've worked on have used a bolt with a 10mm head on them to hold the airbox down. I doubt anything has changed in that department. If you have a set of metric sockets on a 3/8" drive, you should have the right socket to attack this ... unless it is like most any other socket set when working on Japanese cars where the 10mm seems to always evaporate. :o)

  • Thanks for your answer. My interest in the type or code of bolt is it it is rusty. I would need to replace it, then I will need to know which one to buy. I will try the 10mm socket. Commented May 11, 2020 at 3:16
  • 10 mm is very common in Nissan trim. Don't know why one would replace a bolt because it has surface rust. Commented Jan 30, 2021 at 15:27

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .