I have been battling an issue with STRONG vibrations inside my car for quite some time. When the problem started, it would only occur while going uphill or when the car was under a decent load. I originally thought it was my motor mounts, and I replaced the three that had not been replaced recently. Now, all 5 are replaced and in good condition.

Since I can feel the vibration very strongly through the shifter, I then suspected the shifter bushings. I replaced those.

The vibrations started back in June or July, and have gotten more frequent over the past 5 months. I noticed that the symptom started presenting itself more frequently if I had just turned, or was exiting a turn and then accelerating. I suspected the CV axles, and even though there were no ripped/torn boots or signs of excessive wear, I replaced them both. None of these have fixed the problem.

When I accelerate, I can almost feel the car accelerating in small "bursts" when the vibration is most pronounced. The clutch does not slip one bit, and the gears are not hard to shift into (except occasionally I have to try a few times for first gear, when at a stop). I do not drive my car like a madman..just a normal DD. It is a stock D16Y7 with no mods, so there's no excessive strain or stress that I could attribute it to.

I've been doing some reading, particularly about flywheel "hot spots" and I was wondering if this could be attributed to that. I wanted to get some other opinions from you guys before ripping my transmission out..I feel like I've done all of the other "fixes" in vain, and don't want to throw another $250 at it with a flywheel / clutch kit if it's not going to fix anything. Does the Civic utilize a dual-mass flywheel? I read that the dual-mass flywheel is supposed to absorb some of these pulse-like vibrations so the driver does not feel them inside the cab. This could be what I am feeling.. I was trying to Google this and could only find that there were dual-mass and single-mass flywheels available for the Civic..not info about which came stock.

Thanks for any help / tips / suggestions / advice that you guys may give. I'm hoping someone has had a similar issue to this and has chased down the culprit!

Also - while I'm in there, would it be best to replace the rear main seal, or just to inspect it for leaks and if there aren't any noticeable ones - leave it alone?

 

I don't know much about the flywheel, so I can't really help you in the first, more important part of your question. However, I do know that you should ALWAYS replace the rear main seal if you are replacing the clutch. Use an OEM seal.

 

Easy quick trouble shooting first.
Checked all of your motor mounts / torsion mounts?

 

warpage/damaged PP or just other bad habits(not braking the clutch in) etc will cause hot spots.

 

purgat0ry, all of the motor mounts / torque mounts have been replaced and are good.

B_Swapped93, I've never installed a clutch on this Civic so I don't know the break-in procedure that the previous owner followed. It wasn't doing this for the first 35k that I owned it, though. I don't ride the clutch and (to my knowledge) haven't glazed the clutch disc or anything.

I am just trying to see if the vibrations that I am feeling could be attributed to a bad flywheel / hot spots and if that could be the root cause of these problems.

 

Could be a cracked disk. When you get up to speed and shift to neutral does it still vibrate? Any bearing noises?

 

When I get up to speed and shift into neutral, the vibration does not occur. When I get up to speed and am cruising, as opposed to accelerate moderately, it will also go away. No bearing noise that I'm hearing. The vibration is most pronounced when accelerating heavily, and will occur more frequently after I've made a turn - but both axles have been replaced recently.

If it is happening in one gear, then I can shift to the next gear and it will go away - leading me to believe that after shifting, the clutch disc has mated to a different section of the flywheel and making the vibrations go away. Does that make sense?

 

You could always lift your vehicle off the ground (SAFELY and SECURELY - perhaps with the tires removed) and see if you still have the vibration. If not, it might be a suspension component, or even your tires/rims? Have you checked your tires and rims for dents, balancing, or even a defective tire (flat spot, bulge, etc)? I would try to isolate the problem before you start throwing money into it... might save you a buck or two. I had an older vehicle that acted the same way as what you describe. Was getting ready to pull the tranny, until I realized that the u-joint had crapped out. Saved me time and cash...

 

^^ That's a pretty good idea. The tires are new, and this was happening with the old set of tires as well. Alignment is good, and tires were balanced when they were mounted. Suspension components are in pretty good shape - tie rods (inner + outer) were replaced, as well as all 4 struts/shocks.

I will look closer at the upper and lower ball joints, as those haven't been replaced by me. I think it will be hard to replicate the problem with the vehicle off the ground, since it usually happens under load =/ but it's worth a shot. Any other protective measures to take when driving the vehicle while it's up in the air like that? I was going to do the usual, which would be a jack stand on either side, e-brake pulled up, and rear tires chocked with pieces of wood.. and for safe measure I'll even point the car UP my driveway =p

 

Sounds like inner CV's. What were axles replaced with?

Most of these remanufactured units are garbage. Some people say that Carquest or Napa ones are OK, but I've gotten duds from both places. Cores are high mileage and heavily scored. Bearings are replaced with chinese equivalents and repacked with low quality grease.

 

They are replaced with Duralast (AutoZone) replacements..they have limited lifetime warranties, but the guy said if I bring them in to make sure they are separated inside the boot I guess to cover their asses?

I don't know how I'd test whether or not I got a bad pair of axles... and it will happen after turning both left and right, so wouldn't that indicate both rather than just one?

I lifted the car and accelerated through all gears and was not able to replicate the problem. I'm convinced it will only happen when accelerating moderately hard (not flooring it, just getting up to speed) or after a turn, like if I'm accelerating out of a turn on an on-ramp or something similar.

 

You could always resurface the flywheel. There's plenty of youtube videos on it. Then you'd only have to pay for the clutch and throw out bearing. That is if it's really the flywheel that's the problem...

 

I know you said you replaced some of the motor mounts, how about the ones you did not replace, what condition are they in?

 

Another thought, if you grab the axles do you have a lot of play? I wonder if the diff bearings may be going bad and the side load of turning the wheel is loading them up causing movement?

 

When I first got the car, the driver's side motor mount was completely broken - I replaced that first and foremost, and also replaced the lower torque mount on that side. Then when these vibrations started happening and I was suspecting the other mounts, I replaced the T-bracket mount, the transmission side mount, and the transmission side torque mount.

Are you asking me to disconnect the axles from the hub, and then try to wiggle it backwards / forwards? Or just get under it with wheels on / everything still connected, and try and shake it (back and forth or side-to-side) a bit? I could do that and post a video to see if that could be the case. Then I'd be in for a used transmission, flywheel and clutch since I'd be there already..that would be a BLAST. =p

 

Up and down, side to side movement where the cv axle goes into the tranny. Is there a lot of play?

 

Sorry it took awhile to get these videos made / uploaded.

Here's the first one, which compares the two CV axles:
(In this video, I mistakenly say that there's NOT a big difference between passenger / driver's side, which is wrong. It seems there's a good bit more play side-to-side in the passenger than the driver's side).


And the second video is shorter, but emphasizes the difference between the passenger and driver's sides.

 

Update: Replaced passenger CV axle today, and the vibrations still occur. The passenger CV axle does not have as much side-to-side play as it did in the previous video.

Differential bearings?? If this is indeed the problem, would it be more cost-effective for me to remove the transmission myself, take it to a shop to get the differential bearings replaced, and then reinstall it (unknown cost)? Or purchase a used transmission for $50-$200 and maybe run into this problem (or other unknown problems) later on down the road with that one?

 

did you check your tierods ball joints etc ?/ engine mounts

 

All 6 engine mounts have been replaced recently and are fine - tie rod ends (inner and outer) were replaced when I got the car (40k ago) and still appear very good. And I looked at the lower ball joint today while under there and it's doing good as well.

I've thought of another culprit..wheel bearing? Wouldn't that present itself as a constant grinding noise and not a harsh vibration like this?

 

you'd know a wheel bearing going bad it howls....never heard of them causing vibration my guess something's loose as in check all your suspension bolts etc. as for that driveshaft it's fine mine are like that too both my cars.

 

OKAY so big update: I might have fixed my problem. Yesterday I had an actual Honda mechanic friend drive the car and say he thought it was the engine mounts (even though I replaced them all - they were not OEM; most were from RockAuto).

We got to talking about it, and he popped the hood to take a look to see if anything obvious struck him. He noticed something that I had not noticed...a pretty big deal, but one of my bolts going from the transmission into the engine was backed out about 1/8", and the one beside that was backed out about 1/16", and the one beside that was MISSING. An empty hole (the one towards the slave cylinder).

I went to Pull-a-Part today, snagged three new transmission-to-engine bolts, and was able to just tighten down the one bolt that was sticking out about 1/16th". The other one, however, had chewed up threads on the end of it so I replaced it with one from Pull-a-Part.

The missing one, however, is another story. I poked around in the hole with a screwdriver and I'm 99% sure that the previous bolt is BROKEN off into the engine. I might try to drill / use an extractor bit, but seeing as how I can't even get my face level with the hole to confirm a broken bolt, I don't know how accurate I will be with a drill / extractor bit combo (as far as getting in the center of the broken bolt).

So long story short, I test drove it for about 10 minutes and it didn't vibrate at all. I will have to test it on a longer drive in more conditions to be sure, but cross your fingers for me. Could something as simple as that have been the culprit all along?!?! Anything like that happened to any of you?

I feel SO stupid.