Honda vibration at idle in gear solutions?

[dan_erickson]

I have a 2015 Accord V6 and have the famous vibration resonance at idle in gear, worse with the AC on. My car has 104,000 miles and have done quite a bit of maintenance along with a few extra and just can not figure this one out.
Engine oil and trans fluid are always changed on schedule
Timing belt, tensioner, water pump was recently done
Changed all the engine and transmission mounts with OEM Honda parts because this issue seems like that would be the solution.
checked the exhaust and nothing is touching. All hangers are sitting right.
Cleaned the MAF sensor and throttle body
I have had the car on the lift multiple times and have been under the hood looking for anything out of place that may be transferring noise
I have done all this work and the issue is not any better or worse at this point. Also it just crazy that this V6 that’s suppose to be so sliky smooth sounds like a old clapped out 4 banger at idle.

 

[AutoMechanic]

Fuel pump or filter maybe?

 

[atikovi]

Heat shields?

 

[incognito_2u]

Just throwing this out there, but truth be told, I really don’t know to much about Honda engine design.
I assume the plugs are good.....
You say you cleaned the TB.....I know with the Corollas, just spraying the TB with cleaner doesn’t cut the mustard........you have to remove the TB and thoughly clean it and the Idle Air Valve front and back. Is that how you cleaned it?
Not judging, just clarifying......I know and have first hand experience with taking the easy way out and doing it properly!

 

[oldhp]

Vacuum leak??? Power brake booster leaking or hose to it?

 

[ctechbob]

Don't see mention of a valve adjustment in there, nor sparkplugs. Both are due. The valve adjustment can effect idle quality, as can the plugs, but the J-Series is generally pretty easy on plugs.

 

[dan_erickson]

Don't see mention of a valve adjustment in there, nor sparkplugs. Both are due. The valve adjustment can effect idle quality, as can the plugs, but the J-Series is generally pretty easy on plugs.

Forgot to mention that I replaced the plugs at 100k. I always thought the valve adjustment was something that most people didn’t do. Maybe I’ll inquire about that.

 

[dan_erickson]

Vacuum leak??? Power brake booster leaking or hose to it?

Can’t find a leak and computer showed that everything is normal

 

[dan_erickson]

Just throwing this out there, but truth be told, I really don’t know to much about Honda engine design.
I assume the plugs are good.....
You say you cleaned the TB.....I know with the Corollas, just spraying the TB with cleaner doesn’t cut the mustard........you have to remove the TB and thoughly clean it and the Idle Air Valve front and back. Is that how you cleaned it?
Not judging, just clarifying......I know and have first hand experience with taking the easy way out and doing it properly!

I did take the throttle body off the car and cleaned it well, both sides of the plate and all.

 

[ctechbob]

Forgot to mention that I replaced the plugs at 100k. I always thought the valve adjustment was something that most people didn’t do. Maybe I’ll inquire about that.

Honda changed the recommendation over the years. In my 2003 it was called for around the same time as the timing belt, later on they said to only do it 'if the valves are noisy'. The big problem with that is, tight valves don't make noise. You'd much rather have a noisy valve than a silent one. Tight valves leak and burn, loose ones just make noise and maybe lose a tiny tiny % of performance.

 

[vw7674]

I imagine this V-6 has a harmonic balancer or balance shaft(s). Could be a slipped harmonic or an out-of-phase balance shaft.

 

[dan_erickson]

Honda changed the recommendation over the years. In my 2003 it was called for around the same time as the timing belt, later on they said to only do it 'if the valves are noisy'. The big problem with that is, tight valves don't make noise. You'd much rather have a noisy valve than a silent one. Tight valves leak and burn, loose ones just make noise and maybe lose a tiny tiny % of performance.

So I called the Honda dealer for a quote on a valve adjustment and when they would like to did the job. The service writer asked me how do I know the car needs valve adjustment. I said well in at just under 105K and I’d like it done. He gave me some flak about that, told me it’s $500 and that it’s not needed.

Called the Indy mechanic that did my timing belt a few months ago and said sure we can get you in next week for that. He said that they are usually all out of spec a little. But, nothing serious that would effect idle quality, unless I have one that is so far out it’s about to wipe out the cam but doubts that. Waiting on a quote for the valve adjustment plus 2 valve cover gaskets.

 

[ctechbob]

Replace the 6 tube seals while you're in there. Shouldn't add much, they're something like $2ea from the dealer. Also, insist on OEM VC gaskets, I've had bad luck out of aftermarket ones.

 

[meep]

2015 vibration at idle? Did you check the TSBs? Our Crv (2015) had this. The solution was new radiator mounts and headrests, I kid you not, and it worked - it changed the resonance of the vehicle. I wouldn’t have thought it would work but that’s what the tsb said, and they did.

other than that, I’d be all over the engine mounts, inclduing the upper mounts.