Engine Noise after Lighting Install

Hi All,

Looking for a little feedback. Had a roof light bar (BD XL Linkable) with chase lights, and ditch lights (where they normally go at corners of the hood) installed on a prinsu rack. The wiring runs down the sides of the windshield (tucked in) and into the engine bay. The ditch lights are wired to the engine bay as well. In the engine bay there is a switch-pro, which is of course wired through the firewall into the cabin.

Since the install, I have noticed about 30% more engine noise. Louder on startup, louder on acceleration, I can even hear the intake (stock box with just a K&N filter) a little. It's almost as if there is a microphone in the engine bay and it is transmitting all sounds to the cab.

It's certainly not terribly annoying, I just want to know why it could be, so I can accept it and move on. Possibilities:

*Perhaps there is a small trim piece around the cowl that had to be removed for ditch lights? Doubt this as don't notice anything missing.

*Perhaps the wiring down the sides of the windshield are pressing on the trim a bit and adjusting noise reduction.

*Perhaps the wiring through the firewall grommet is causing additional noise. Most likely.

Any other thoughts, anyone experienced this? Haven't had time to dig into it and see if I can pinpoint it. The additional noise isn't coming from anywhere particular (ie through a vent or this side of the dash or the other etc), it's just there.

Thanks for any help!

 

Is it an electronic sound coming through your speakers...? Could be a bad or intermittent ground reaching its way through the system.

 

No, it's definitely not electronic sounding like it is coming through the speakers, I probably shouldn't have led that with the microphone analogy. It sounds simply as if there is now less overall insulation between me and the engine bay. Took it to work this morning, and I'm thinking the firewall (where the wiring comes through) is the most likely candidate. Will have to see if I can duck my big ass head up under there tonight and see if I can silicon anything.

And side note, holy gas mileage Batman with the new roof rack, roam box, and rotopax. Yikes! It was windy this morning but holy smokes, think the trip avg was about 12mpg on my mostly highway 10 mile drive Usually don't care about MPG's, but at $5.30 / gallon this could get interesting.

 

*Perhaps the wiring through the firewall grommet is causing additional noise. Most likely < Yes, most likely. Follow the wires to where they ran them through the firewall and look there first. If it was tight getting the wires through the pass-through grommet it only takes a few tugs to pull the grommet out of the hole. If it is one of the holes above the carpet you would definitely hear it.

 

You get the "ding ding ding winner". Popped my head under there earlier and that is exactly what happened. The grommet is only covering about half of the hole, which is about 3 inches diameter. A decent amount of wires running through there, so I called and they are going to happily remedy tomorrow am. Thanks for the insight, you were literally dead on!

 

I'm going to bet the hole through the firewall. I have a rack with lights and wiring running down my windshield (KC Wire Hider) through the cowl trim piece and into the engine bay. No noticeable noise whatsoever besides wind noise off the four 6" lights at highway speeds. I definitely don't have amplified engine noise. You could throw a bright ass light in the engine bay and poke around inside the cabin to see if you can see daylight.

edit: I was too late, you found it, nice!

 

Im glad somebody nailed it. Good thing too, I was about to say rubber fender liner in front wheel well lol, you know, because it’s pretty much the cause of every 4runner noise lol

 

Sir please kindly knock on some wood for me ! LOL - haven't experienced the fender liner isssue yet but surely its a matter of time. Firewall grommet seated back in place, extra engine bay noise is gone!

 

Curious- is there a problem with the bluetooth switches for lights - types where all you have to do is connect a power line but not have to run a wire thru the firewall? This seems to be a great remedy for all that wiring etc.

 

Link please!

 

https://www.autozone.com/exterior-l...azer-international-wireless-remote/181960_0_0


Also, what kind of wind noise do ditch lights put out?