I've had my Mugen header and exhaust on for about 2 weeks as of yesterday. I did the pocono track day on Saturday and gave my car a good workout all day. As I was leaving the track, I noticed that my car seemed to be running and sounding a little rough. I did not think much of it at the time. I was exhausted and went right home and went right to sleep. I got up Sunday morning and drove around for about 20mi running some errands with the car, and it did not sound rough at all... It sounded like it was back to normal. Then last night, I was returning from my parents' house back to my home down near Philly. I drove about an hour South on the PA turnpike. When I got off my exit onto back roads, I noticed that the car was running rough again at lower RPMs and louder than ever. By this time, it was dark and I couldn't see anything, so I figured I'd just park the car and get up early to look at my car this morning.
My head was spinning with what could be wrong - Did I overrev my motor at the track and screw up the valvetrain? Did I snap the crank pulley bolt like happened in my old Prelude? Did my timing belt ship a tooth or two? Is it an exhaust leak? Is it just my heatshielding rubbing the exhaust again?
Well, this morning I got up early and went out to my car to investigate in the daylight. I noticed right away that there were only 2 out of 3 of the studs that secure the exhaust manifold to the downpipe left. 1 of the 2 looked OK. The other one was almost sheared in two, and one was gone completely. So that's what all my noise and rough running was from...
I went to Midas as soon as they opened this morning because they were closest to me. On the 1 mile drive there, I lost the stud that was nearly sheared before. Luckily the last stud held until I got to the shop. (Otherwise, I would have had my Mugen downpipe drop to the ground and get dented and then dragged down the road...) They got to work on my car right away. The studs had apparently vibrated their way out and the threads on the header flange itself were destroyed. They had to tap new threads and put three new bolts on to replace the studs. They put LocTite on the bolts which they claimed would keep them from virbating out again... So 1 1/2 hours and $128 later, I had my Mugen header fixed...
Weird... that happened with my DC.
I took a road trip from SoCal to NorCal about a week after installing my headers. I didn't notice anything, because there was a crap load of road noise.
Popped the hood to check my intake (it was falling off the tb because of a loose screw, and banging around), and I only had one bolt holding my header to the downpipe. Well, two if you count the one that had backed up partway. The other one, missing completely.
Got some hardened nuts and bolts (I think they were 8 or 9), and haven't had a problem since
Please excuse my spelling in the post title. Speling am not my strong smoot...
I actually got the header used. My friend pretty much installed it for me while I watched/helped. The threads on the header flange seemed fine when we installed it though...
I guess it could be a combination of maybe the studs being torqued improperly and the torture test at Pocono... My friend torqued the studs on the mugen header to the factory specs for the factory header... So that might be a problem, although it made sense at the time... We also did not use LocTite when we installed it initially...
The guy at Midas said he's seen header bolts vibrate out all the time on domestics if you didn't use locking nuts or LocTite...
Andrew
wow close call...it could have also been something the previous owner did...who knows but good thing you got it fixed before anything bad happened. Maybe thats why your exhaust was so loud
Ah yes, I see the problem. If you don't use locking nuts the nuts could possibly vibrate loose.
When I installed my header I got all new hardware from Honda to install it with. I replaced the locking castle nuts that were on the stock header with different locking nuts. I used different nuts because honda did not have the original ones in stock and the stock ones cost around $3.00 a piece (you need 9 of them, ouch). The ones I used are like the ones that honda uses on the rest of the exhaust system. I've never had a problem yet and I've checked the torque on them a couple of times.
Gabe
__________________
03 Black/Black S2000 #2512
04 Eternal Blue Pearl Accord EX-L w/Navi
That's BS. I mean the work- this further confirms my theory that Midas, nationwide, employs morons of the highest caliber that are trained to rip you off, not perform quality work.
Those studs should NOT have vibrated loose. I don't think they require loc-tite, either. If you ever have one of those get chewed threads, you will likely have to drill and retap them. This is also something you don't want to be doing if you can help it, as you can only do it so many times (before you run out of stud sizes.
I suggest you find somewhere else to do the work. That was extremely poor work for them to have backed out, sheared, or anything else.
Originally posted by marcucci That's BS. I mean the work- this further confirms my theory that Midas, nationwide, employs morons of the highest caliber that are trained to rip you off, not perform quality work.
Those studs should NOT have vibrated loose. I don't think they require loc-tite, either. If you ever have one of those get chewed threads, you will likely have to drill and retap them. This is also something you don't want to be doing if you can help it, as you can only do it so many times (before you run out of stud sizes.
I suggest you find somewhere else to do the work. That was extremely poor work for them to have backed out, sheared, or anything else.
umm, I think he had is friend installed it for him, NOT Midas.
I reused the same factory nuts/bolts and didn't use loc-tite for my Mugen header install, and everything has been fine for me so far.
Originally posted by marcucci That's BS. I mean the work- this further confirms my theory that Midas, nationwide, employs morons of the highest caliber that are trained to rip you off, not perform quality work.
Those studs should NOT have vibrated loose. I don't think they require loc-tite, either. If you ever have one of those get chewed threads, you will likely have to drill and retap them. This is also something you don't want to be doing if you can help it, as you can only do it so many times (before you run out of stud sizes.
I suggest you find somewhere else to do the work. That was extremely poor work for them to have backed out, sheared, or anything else.
No. Midas did not install it initially. As I said before, my friend and I actually installed the header... I just went to Midas this morning because they open early and they are close to where I live. Midas was not exactly my first choice, but I had to get it fixed quick this morning and get to work. I thought I just needed them to put two replacement bolts on when I went there. But then they tapped the new threads and put new bolts on without asking me first... If they HAD asked me first, I'm pretty sure I would have just had them do that anyway... I needed to get to work today somehow...
If/when it comes apart again, I will go back to Midas to have them fix it and/or buy me a new Mugen header...
Andrew, you shouldn't have any further problems with the bolts retorqued. I still gotta hammer/bend the heatshield sometime on my car...I hear the rattle from the exhaust going against it from time to time .
__________________
James--'99 Ficus Green Pearl Type SH, 03' Starlight Silver Metallic Pilot EX-L, 02' silver Mitsubishi Galant ES
The value of life can be measured by how many times your soul has been deeply stirred...--Soichiro Honda www.hacstl.com...RIP 1999--2011
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.
By this time, it was dark and I couldn't see anything, so I figured I'd just park the car and get up early to look at my car this morning. 
Linear Mode
