Volant vibration/resonance on V8 Sport

[PerfectAgent007]

Hey guys. To all of my fellow 4Runner brethren running a Volant intake on a V8 has anyone experienced an intense vibration when really stomping on the gas around 2400-2700 RPM? If I'm below or above there's little vibration. It sounds like it's something vibrating inside the cabin on the passenger side. There's nothing in my glove box and nothing that I could see would cause this.

I also put weather stripping on the bottom of the intake box so I know that's not causing this. No deckplate mod by the way.

Anyone go through this? Thoughts/theories?

2007 V8 Sport

 

[forwardnum1]

I installed a Volant last weekend and I also noticed a little bit of vibration on the passenger side. I haven't had any time to investigate further though. Id love to hear what you find.

 

[klennop]

That seems to be just the way it is. Mine does it at higher RPMs only when really tromping on it. Some say it is harmonic resonance which I agree, I wondered if you took the lid off the box would it be less? I think it may just be the normal intake noise amplified by the air box but that is just an assumption on my part.

 

[PerfectAgent007]

Sorry for the late reply, finals killed me and I had to be reborn. Nice to know this is normal.

I agree that it's definitely some kind of harmonic resonance as a result of the extra vibration coming from the engine compartment but I'm still trying to track down what's specifically resonating. Like I said before it wasn't anything in the glove box but I tried holding onto the plastic that makes up the overhead controls. I don't have anything conclusive so I'll have to try again but it's one more possibility.

 

[chaz]

not sure about , normal, mine doesnt do it. u sure its not the intake tube vibrating against the hole box opening? the volant comes with that POS bumper/seal thats used around the edge of the hole.u may want to find something thats firmer. also, if u offroad,where the tube connects to the TB should be checked for tightness, since it can vibrate loose & hit the fan.

 

[PerfectAgent007]

Positive. I use foam weather stripping to form a seal around the pipe and I use the included rubber tube on the other side of the box to provide a seal and vibration dampener against the wheel well. Not to mention I also have strips of weather stripping on the bottom of the box. Nothing at the box is creating the noise, unless I missed something.

 

[SkylineGTRracer]

I'm not familiar with the volant system on the 2uz but does it have bushings on the bottom like an afe?

 

[PerfectAgent007]

If you're talking about the airbox, then no. It uses two of the three factory bolts and those just have a washer that's inside the box. Even if those were rattling I doubt I could hear that inside the cabin.

 

[SkylineGTRracer]

I would say it's worth trying.

 

[Aquabear]

I would say it's worth trying.

I agree. I just put in multiple rubber washers/bushings under the AFE airbox because it was not rattling due to OEM bolts not holding the AFE box in. It is 90% better now, my front passengers dont complain about noise/vibration when I gun the gas.

Thought I had posted pics. Will try.

 

[PerfectAgent007]

I put in half-inch foam weather stripping on the underside of the box so unless the bolt itself is rattling the box isn't the issue since the foam is absorbing all vibrations. I will look into taking the box's cover off though and see what happens. It'll have to be tomorrow though.

 

[Aquabear]

I put in half-inch foam weather stripping on the underside of the box so unless the bolt itself is rattling the box isn't the issue since the foam is absorbing all vibrations. I will look into taking the box's cover off though and see what happens. It'll have to be tomorrow though.

Yours might be different but weatherstripping wouldnt have solved my problem. I had to sandwhich rubber then metal washers together. Mine was bad you could rock the box with your hand and know it wasnt secure whcih would easily cause the loudness and vibrations.

 

[PerfectAgent007]

Mine was bad you could rock the box with your hand and know it wasnt secure

Considering the Volant box uses two of the three factory bolts it's probably true of anyone who's installed it. I'll grab some rubber washers too, see what happens.

 

[Aquabear]

Pics of the AFE air box bolts with rubber/metal grommets. Took time to reduce them down to a size I could download.

I hope they help.

 

[CZ75]

not sure about , normal, mine doesnt do it. u sure its not the intake tube vibrating against the hole box opening? the volant comes with that POS bumper/seal thats used around the edge of the hole.u may want to find something thats firmer. also, if u offroad,where the tube connects to the TB should be checked for tightness, since it can vibrate loose & hit the fan.

I like how you sealed the tube to the box. Much better than what Volant provides. Can you elaborate on what you did?

 

[rockwall]

Good thread guys. I never really minded the vibration and thought it was just how it is. I will try your ideas.

 

[klennop]

I just got done with a 3500 mile road trip hauling a 4 adults, cargo area full, Yakima roof rack with roof bag full, 6.5' x 11' trailer with 3 motorcycles 3 large loaded coolers, etc. It was loaded pretty good. I went from Wisconsin to Tellico Plains Tenn to New Bern N.C. lots of running around in the mountains and then back home. I have the Volant and Magnaflow combo. I will be doing a writeup on this later but I learned a lot about the Volant from hauling up the mountains.

The resonance is NOT from touching any part in my vehicle. When driving around "normal" the heavy resonance sound happens for a short while and then goes away when you are getting on it. I really should have took video but I had a lot going on and not a real free hand when I was experimenting in the mountains. When pulling a load up a steep long incline over and over I was able to find the following out. The resonance sound is really loud but then it changes and mellows out even with the RPM's staying constant. Because of the heavy load, I could duplicate it over and over and the 4runner was staying in a lower gear working harder vs just quickly going to the next gear. I think the ECU takes initial readings and then changes the airflow which in turn changes the resonance. So I am 99.9% sure that it is the VVT-i which makes the resonance sound not any rubbing, etc. on anything.

 

[CZ75]

Tube to box mod on Volant

Finally got around to doing this. Thanks to Chaz for providing info on how he did his mod.

I went a bit different route since I found this bushing in the plumbing section at OSH today. The bushing is used when a 3" drain pipe is stepped up to a 4". $4.49.

Cut it in half with a BFK.

This bushing slips over the Volant tube perfectly. Nice and snug. I removed the rubber tubing from the originally provided seal that is made up of a u shaped channel with neoprene tube attached. My tubing was beginning to come apart from the flexable channel already. There was about a 1/16" gap between the bushing and the flexable channel when the tube was removed.

I used black RTV sealant to seal this 1/16" gap aroung the bushing from both sides. Should be able to slip the tube out of the bushing if I need to service the box for some reason... or just reseal with more RTV.

I also plugged the front hole with the 3" pipe cap as Chaz recommended.

I'll see if this reduces any resonance on my way to work tomorrow.

 

[chaz]

looks like a nice clean job.

 

[CZ75]

Capping the front port and sealing the intake tube to the box made a big difference to the amount of resonance and vibration generated when stepping on the gas (according to my calibrated ears ).

Previously I would mainly hear the intake and now I mainly hear the exhaust from the Gibson CATback.

I'll try removing the cap on the way home to see if the resonance comes back.