Strange Vibration at Idle
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Strange Vibration at Idle
Hey guys, I'm hoping someone here can help me figure out what's going on with my car.
I have a 2010 G37 Sedan with 135K miles. The first thing I did when I got it was install the Tanabe Axle Back exhaust. Second thing I did was swap the resonators to the Vibrant 1790 bottle style resonators. Lastly, I installed Fast Intentions RHFCs. Now, all was good until I installed the RHFCs. As soon as I turned on my car, I noticed a strong vibration coming from the engine. Over time I'm guessing the car has learned about the new mods and has settled down a bit.
Things I've tried:
The vibration isn't constant either. Once I'm idle for more than 5 seconds, the car begins to vibrate. Sometimes it goes away after a little while sometimes it doesn't. Sometimes I see the RPMs drop to about 300~400 then quickly go back up to where it's supposed to be around 650. RPM dips don't always happen. It vibrates regardless. Vibration is worse when in reverse gear.
Is this just something that comes with having a modded car? I did call Fast Intentions and they did mention that added vibration is not a side effect of adding their cats.
I've searched the forums and other sites and wasn't able to find anyone else with an issue like mine. I hope someone here can chime in on my situation.
I have a 2010 G37 Sedan with 135K miles. The first thing I did when I got it was install the Tanabe Axle Back exhaust. Second thing I did was swap the resonators to the Vibrant 1790 bottle style resonators. Lastly, I installed Fast Intentions RHFCs. Now, all was good until I installed the RHFCs. As soon as I turned on my car, I noticed a strong vibration coming from the engine. Over time I'm guessing the car has learned about the new mods and has settled down a bit.
Things I've tried:
- Bought new O2 sensors that go on the cats.
- Reset ECU.
- Performed the Idle Air Volume Relearn procedure.
- Changed Oil. (Mobil 1 Synthetic).
- Cleaned throttle bodies.
- Replaced both engine mounts. (Helped a little but vibration is still there).
- Changed filters.
The vibration isn't constant either. Once I'm idle for more than 5 seconds, the car begins to vibrate. Sometimes it goes away after a little while sometimes it doesn't. Sometimes I see the RPMs drop to about 300~400 then quickly go back up to where it's supposed to be around 650. RPM dips don't always happen. It vibrates regardless. Vibration is worse when in reverse gear.
Is this just something that comes with having a modded car? I did call Fast Intentions and they did mention that added vibration is not a side effect of adding their cats.
I've searched the forums and other sites and wasn't able to find anyone else with an issue like mine. I hope someone here can chime in on my situation.
IIRC, for about a year, my exhaust was configured with FI RHFC's matched to the OEM catback. I had a resonance at idle too, although there was no RPM issue like you're describing. Plus, mine is a 6MT.
Anyway, the resonance went away when I removed the midpipe dampers. There are solid rubber dampers clamped to the OEM exhaust, about the size of a shotglass.
Also, FI cats don't support using the OEM cross brace which connects the original cats to the underside of the transmission. In order to use that brace with FI cats, you need to do some customization.
https://www.myg37.com/forums/g37-sed...tions-hfc.html
Anyway, the resonance went away when I removed the midpipe dampers. There are solid rubber dampers clamped to the OEM exhaust, about the size of a shotglass.
Also, FI cats don't support using the OEM cross brace which connects the original cats to the underside of the transmission. In order to use that brace with FI cats, you need to do some customization.
https://www.myg37.com/forums/g37-sed...tions-hfc.html
