[Tex Nomex]

I’m taking the night off, I ordered an NGK coil from rock auto to rotate through and see if the weak coil theory is even possible. If not, mine all have 230k so I’m sure I’ll need it soon enough anyway. I’ll order an OEM Acura rear mount after I try the coil. Chris looked at the tensioner pulley bouncing and said that normally that means something is going on with the motor, I will double check my pulleys again but I used a Gates tensioner assembly, a NAPA reman power steering pulley, an Aisin water pump, and right before I bought it the AC compressor and alternator were replaced, remans I’m sure. I want to take the belt off and run it and see how the vibration is with no accessory pulleys loaded on the motor. I’ll probably do those two lower tranny/cradle mounts since I have those too now. But to put your hand on the valve cover you feel what feels like a consistent super light miss of some kind. I know I have good compression but I’m wondering if something could be going on with the valvetrain? The valve adjustment changed nothing but it did rule that out, I hope. Oh yes and I’m learning some more about wave forms on scan tools, watching live data im seeing my long and short term fuel trim want to run at about +4% but I don’t know enough about that to know if that’s indication something is suspect or not.

Ideas:
Running lean - could be fuel pressure regulator / fuel filter / fuel pump, dirty, bad injector(s), dirty MAF
Are the belt tensioner markings within the nominal range? Yeah, remove the belt and see if that helps.
Crank Angle Sensor.

When you replace the rear and bottom mounts, make sure to completely disassemble the mount beneath the battery. It won't allow you to jack the tranny up high enough to insert the tranny mounts.

 

[JMD07ASPEC]

Hi Guys, first post here. 10 year Tsx owner (2004) and I just purchase my second (07 A-spec) and I have been doing the work on my car as long as I have owner it.

OP, I really need to clarify something: You say "rough idle" but are you actually referring to engine vibration in the cabin of the vehicle? The reason I ask is I had A LOT of "slop" in the drive train of my 04 when going from drive to coast back to drive. Through research many people pointed to the compliance bushings in the lower control arms. I replaced those with low cost aftermarket full control arms and though my steering was tighter, the slop didn't go away. Next on the list was motor mounts. Again, I ordered a low cost aftermarket set of mounts, front, side and rear. I only replaced the rear and the excessive vibration arrived - still with a medium amount of drive train slop. I'm actually planning on swapping the original rear mount back in (this is not fun) and then putting the after market front mount in.

Also, I read somewhere in this thread that the rear mount is vacuum actuated. This is not the case, at least not on the 04-05 version.

 

[Tex Nomex]

The rear mount should be the fluid-filled type, the front mount should be vacuum-actuated.
Cheap CV axles can also cause idling vibration and acceleration vibration problems.

 

[Midnight Mechanic]

The front mount is vacuum actuated, not the rear. You definitely want OEM for the front mount, that’s what I ordered to replace the aftermarket I had bought that would not hold vacuum (meaning it actually had a vacuum leak). That did improve the transfer of vibration to the car but it’s still obvious that it’s there.

update for today- I ordered an OEM TEC / NGK ignition coil and rotated it through one cylinder at a time and started the car/tested it in each cylinder and this did not change anything. I’m still waiting on the OEM rear mount to arrive from Acurapartswarehouse. It won’t arrive til next week so in the meantime I might rent the fuel injector test kit from auto zone and test the pressure. Watching An Eric the car guy video today he mentioned that pressure doesn’t necessarily reflect flow, but I’m guessing that is more relevant to high RPM flow not keeping up. All of my injectors ohm’ed at 11 ohms so I think the injectors are all fine.

Hi Guys, first post here. 10 year Tsx owner (2004) and I just purchase my second (07 A-spec) and I have been doing the work on my car as long as I have owner it.

OP, I really need to clarify something: You say "rough idle" but are you actually referring to engine vibration in the cabin of the vehicle? The reason I ask is I had A LOT of "slop" in the drive train of my 04 when going from drive to coast back to drive. Through research many people pointed to the compliance bushings in the lower control arms. I replaced those with low cost aftermarket full control arms and though my steering was tighter, the slop didn't go away. Next on the list was motor mounts. Again, I ordered a low cost aftermarket set of mounts, front, side and rear. I only replaced the rear and the excessive vibration arrived - still with a medium amount of drive train slop. I'm actually planning on swapping the original rear mount back in (this is not fun) and then putting the after market front mount in.

Also, I read somewhere in this thread that the rear mount is vacuum actuated. This is not the case, at least not on the 04-05 version.

 

[Midnight Mechanic]

Alright, the moment I have been waiting for has finally arrived, it is fixed!!! I installed the OEM Acura rear motor mount, and while I was at it I installed the lower two tranny mounts with Anchor brand, but I’m sure that was inconsequential to my positive outcome. Basically about two years ago I used the cheapest mounts I could possibly find to replace the four big ones, and ad I compared the rear mount tonight with the OEM Acura one, not only was it ROCK hard and totally solid with no give (meaning it was solid rubber and not hydraulic), it was a whole inch too short in overall height 😯😯😯
I got ahold of a mount made for another application most likely but because the bolt pattern was the same I never noticed, and the old one was fully busted out so it was immediately obvious if I did compare them, which I doubt I even did. I fired it up tonight after replacing it and it felt like a brand new car. AMAZING. I did notice a difference after replacing the front vacuum operated mount with an Acura OEM one last month too but this rear mount was the BIG one that really was shaking the whole car hard. Anyone who stumbles across this, if you’re having intense vibration issues, get OEM Acura mounts for the front and rear and try that first. They’re $150 each from Acura parts warehouse but it was 100% worth that, the difference between crappy aftermarkets and these is literally night and day. Several professional techs sat in it and all thought it MUST have a vacuum leak, clogged fuel filter, weak coil, something mechanically wrong. We were all wrong and it really was just this simple. Also, doing those lower tranny mounts is a bear and I don’t feel like it’s worth the trouble if they aren’t broken. Also, those anchor aftermarkets didn’t fit quite right so I wouldn’t recommend those either simply for the fit issue, I’m hoping that doesn’t lead to premature cracking/breaking.
I won’t know what to do with myself, almost three years of getting rattled morning day and night, now it feels like a brand new car.

 

[Midnight Mechanic]

A huge thanks to all you guys, especially Tex, for the guidance and help, I really appreciate it!!!

 

[Tex Nomex]

Awesome! So glad that was it!
You're certainly welcome for the help.
This thread needs to be pinned up top.
Having seemingly unsolvable vibration problems is its own special kind of demoralizing hell.