Hey guys

​​​​​​Owned my s2000 for about a year and a half, just running into a first major issue. I've been using this forum for guidance with little tasks and it's been great, but I can't seem to find a thread detailing what I'm running into.

Basically I've got a weird intermittent vibration. Pretty significant feeling, along the lines of a flat tire. That said, it's intermittent. The first several times it happened after sitting in bumper to bumper traffic but now it seems to be nearly constant. Vibration is the same magnitude whether I am on the throttle or not, and is the same even if I push in the clutch. The car also stops itself significantly faster when the problem is happening, like having a light foot on the brake, but feels more like someone pumping the brakes for a millisecond on each rotation. A couple times I've smelled something during/after that I can't place. Maybe a little like burnt clutch/plastic(?)

Each time the problem has stopped if I stop the car for a couple minutes, and it's back to smooth driving. Today it did this twice on my commute home. The first time I was getting out of traffic and it vibrated for ~3 min before smoothing itself out at speed. The second time it started up without any traffic trigger, then went away when I stopped at a light, only to reappear a few blocks later and persist until I got home.

My first thought was tires. I'm running a fairly new (3mos) set of summer tires in the cold season in the mid Atlantic. That said I can't think of why it would be intermittent if it were the tires. Saw the issues people have had with CV cups so I bought the materials to do that swap, but the issue seems different than that. Maybe a wheel hub? Defective tire that gets wonky when the tire's temperature goes down? Driveshaft? I'm thinking it's not spark plug related since the clutch off behavior is the same as clutch engaged...

Please let me know if you've run into something similar or have any ideas! Suspension is stock, brakes are hawk hp+ (5 mos old), tires are michelin pilot sport 4s (3 mos old) if any of that is relevant...

 

From what you have said I would guess first at a brake/rotor/caliper issue. I would also take a look at the parking/emergency brake to ensure it is working properly and is completely disengaged when the handle is stowed.
May need a buddy for some of the checks as you operate the controls.

 

Thank you. After re-reading my own post I had the same thought and was just looking up causes of calipers sticking. I'll pull the wheels off tomorrow morning before I head to work to inspect and clean them... And maybe that's all it is. Hadn't really occurred to me as the problem source because I've never had an issue with a caliper before and they'd been on for quite a while, but tgen it wasn't cold for those past months.

I'm thinking that smell I couldn't place is likely burnt brake pad material... Will update tomorrow! Checking the PB is a good call too if calipers look otherwise fine. Thanks again for the help!

 

You haven't changed the clutch, recently? Hope it's a simple brake or tire issue.

 

Sounds like sticking calipers to me. Easy fix and worth the check. Pull your wheels off starting at the front and loosen the caliper from it's guide pins then pull the guide pins out of their rubbery sleeves and check if there's any grease on them at all. If they're dry you need to grease them. Tighten everything up and monitor the car from then.

 

Reading it, brakes also jumped out at me. Like a pad that is getting rocked out of place, or is sticking crooked, etc. No lube on the metal surfaces the pad slides on, etc. Maybe rusted up, etc.

Also maybe the caliper slide pins. Like they're loose. Or corroded. Or maybe there is a rough spot on the pin.

Next time you smell them, pull over, and see which rotor is way hotter than the others. Then you'll know which corner it is. I would get a $20 laser thermometer from Harbor Freight. Or just a spray bottle with water. See which rotor hisses loud when you spray a little on it (only spray a very little!)

 

Sticking brake caliper also my thoughts on most likely based on info.

Is there a particular rotor that is much hotter then the others after a normal drive? Take a look at the rotors and also look for signs of high heat/blueing, or anything else that stands out different from the others.

 

Guessing front drivers side was problem. Did fronts today. Some extra wear, Paint melted from heat on one pad. Cleaned, greased, reinstalled. Testing tonight. Will update from a computer tomorrow.

One clean pin one dirty

 

Front drivers smelled worst y/d, looked bad today so I'm guessing that's the one that needed attention. I'm going to do the rears just in case this weekend. Test driving it tonight.

 

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did that to The fronts hope it did the trick. Doing rears this weekend if not. Went ahead and disassembled//greased/rebuilt the whole assemblies in front.