As stated in the title my Accord has begun to bang into reverse pretty hard since the temps have begun to go down (first thing in morning). The colder it is the harder the bang and it goes away as the engine warms. I haven't tried it into drive yet but will in the AM. Any help would be much appreciated before I break something.

I see there are similar threads so delete this if needs be.

 

If the idle speed is too high(> 2000 rpms perhaps), then a hard shift is expected. Solve the high idle problem.

If idle is lower (< 2000 rpm), then problem may lie w/ AT.

I did not see any specific guidance in the shop manual for hard P-R or N-R shifting. There was guidance on a late or delayed shift from N-R. If you are accelerating engine before shifting, this might cause a hard shift.

Also in some cases, a fault code on AT may not set check engine light. Check for codes w/ an obd2 scanner.

good luck

 

Thanks for the feedback. This occurs with normal fast idle following start. Motor mounts were replaced some months ago so have discounted them. Once the engine and trans warm up it shifts normally, and has only just begun this symptom as the weather cooled this fall. The colder it is, the harder it shifts and I'm afraid it could lead to damage if it occurs too many times. We'll just have to plan more time into each excursion and allow the car to warm up sufficiently before driving. It bangs going from N to R also and I'm pretty sure it's Xmission related.

I'll scour the internet for any other help and contact an acquaintance who was a Honda tech for a number of years. Any info related to a fix will be posted. Again, thanks! RT

 

My first thought was this could be a motor mount issue. Even though they are fairly new, I'd still check the motor mounts. Seen where new parts fail prematurely or even right out of the box.

 

My thoughts too on both a bad/worn mount, and bad/defetive p
new parts (aftermarket). I've got a new fuel filter sitting on my wall of shame. You can't blow thru it, and it was like this right out of the box.
My wife's car makes a "thunk" sound when 1st put into reverse in the morning, but doesn't do it any other time. I've tried looking for what's causing it, but haven't found anything yet.

 

I found a bad rear motor mount by having my wife hold brake w/ hand brake also set, place trans in R, and goose the throttle slightly. I was able to observe the broken motor mount from pax side fender w/ a light. This was a 94EX, so might be different for your model but rear mount is still in same position.

good luck

 

You say it occurs with "normal" fast-idle after starting. At what RPM does it happen? As it warms up, at what RPM does it stop banging?