Hi,

I am having a few "minor" problems with my automatic transmission (1997 accord f22b1 vtec / 140000km ).

When i start the car in the morning (engine cold), if i shift from park (or neutral) to reverse, i can hear a loud noise under the hood and i can feel a hard shock as the transmission shifts to reverse, it feels like the engine is about to be torn from its mounts...

This happens only for shifting from N or P to reverse and only if the engine is cold. After the car warms up, everything goes back to normal... or so i think, i mean i still can feel it as the reverse engages, but nothing unusual.

The engine and transmission mounts are all ok, i drained/refilled atf-z1 about 3 times over the last month, cleaned the solenoids, but still no improvement.

Also, at low rpm, the transmission shifts kind of harsh, but i think this is normal for the 5th gen accords.

Any ideas what is going wrong, TCM problem or is my transmission dying here ?

Thank you

 

From what you are describing, the mount (rear) could be a problem. That one is harder to see and has a vacuum control on it. If you have a hand held vacuum pump, you might want to remove the hose from the rear mount and see if it can hold vacuum. You can also put the vacuum pump on the actuator and see if there is vacuum available when you rev the engine up to past 700 rpms.

You may want to have someone shift the car from park to reverse, while you watch the engine. If the engine moves significantly, then suspect a motor mount.

Here is a link with some similar info.

https://www.hondaaccordforum.com/m_3..._1/key_/tm.htm

 

Update:
PAHonda, you were right, the rear mount was completely shot ( broken in half with some oil inside).
I put a new mount yesterday night, shifting is more smooth, but now the car vibrates a lot, like never before, i can feel it in my teeth
I still have to check the mount solenoid, but i doubt that alone can get me rid of the vibrations.
I'll keep you updated.
Thanks a lot guys.

 

Does it vibrate all the time or only at idle, under trans load? Vibration at idle under trans load usually results from too low idle speed caused by lack of idle compensation by the idle air control valve. If idle vibration improves dramatically w/ tiny addition of throttle, the IACV problem is likely.

Has timing belt maintenance been performed recently or ever? Misalignment of balance shafts during timing/balance shaft belt replacement could lead to constant vibration.

good luck

 

It vibrates at idle and worsens when i put the car under trans load, however, rpm seems steady, no rpm drop under trans or A/C load.
I did some maintenance on the iacv and fitv a few months ago and they should be still clean

I also did a complete engine rebuild in september, including all belts (timing, balancing...).

Now that you mention it, i am not that sure that the balance shafts are " aligned", i mean i did the job myself with a friend mechanic, we were very careful to follow the manuals instructions regarding timing belt alignment with the piston1 at tdc, we made sure all the notches at the sprockets and water pump were aligned... but so far i remember the balance shafts were very straightforward and we didnt even have to think about aligning them. The job was done while the engine was out of the car.

Is there more than 1 position to put the balancing shafts ?

I will double check the manual and the car and i'll let you know how it goes.

Thank you again.

 

At TDC, the front balance shaft has a mark on the shaft that should line up at 12 o'clock and is easy to see.

The rear balance shaft has an access hole on the back of the engine block. You will have to remove a bolt to get at it. You will be able to insert a 1/4 inch drill bit in about 3 inches when at TDC. The bit will go in much less further if that balance shaft is out of line.

You can download a 94 shop manual in the online manuals thread in the DIY section that will cover the timing belt installation. The 94 is almost identical to your 97.

 

PAhonda,

just came back from the mechanic, we reviewed together the engine rebuild that we did in september, and as a matter of fact, we still have in the garage the old oil pump housing, and looking at it, i remember we lined up the balance shafts correctly, i remember i had a printout of the manual while we did this.

The mount soleniod tested fine and the mount actuator moves as it's supposed to.

We also tried to modify the vertical positions of the front and rear mount, but no success, the vibrations are still there.

The mechanic thinks the mount is too hard and transfers all the vibrations to the cabin instead of absorbing them. He's seen this before with other cars, not specifically with honda.
This is the mount i bought : http://cgi.ebay.com/ebaymotors/ws/eB...AQ:MOTORS:1123

I am considering 2 options now :
1- Drill holes in my brand new mount to "soften" it and drain the fluid that's inside, meaning i will lose the "enhanced" feature of this mount with the 2 separate chambers acting as one or separately depending on rpm...

2- I have a used rear mount from a 1996 honda accord with manual transmission, it's not exactly the same size and only 2 bolts can be used to attach it out of 3, but it feels more soft than the new A/T mount i have now. I am thinking i might modify it, try it and see it it will do a better job at filtering the vibrations.

I am open to all suggestions.

Thanks again

 

I will double check the balancer shafts tomorrow just to make sure before altering the mounts.
I'll take pics.
Have a nice week end everyone

 

Ok,
it took about 5 hours to get to the belts and put everything back together.
Everything checked out fine, all belts were correctly aligned including the 2 balancer shafts.
The situation is still the same : The car vibrates like a tractor since i installed that new rear mount, i think i will remove it and put back the old one that is broken in half, at least i didnt have these awful vibrations before.
It is so frustrating that i spent 2 hours to put the new mount, 5+ hours today to double check the timing/balancer belts and i am still stuck with vibrations that i didnt have before this new mount.
My friend mechanic thinks the new mount is bad quality and its rubber is too hard...
any ideas ?
Thanks

 

Others on here suggest to get honda parts. Look at tasauto.com for prices or call your dealership.