I recently ran over part of a tire on the freeway that slapped the underside of my car (2001 Accord). The check engine light is now on, and the transmission is reacting funny, so I’m pretty sure the two are connected. I’d probably best describe the transmission response as jumpy. The car runs well enough, but the shifting points are off. I’m mostly just trying to see what could be causing the problem that could have been the result of a hit to the underside of the car.
Have a mechanic put your car up on a lift and inspect it for damage…This is not rocket science…
Caddyman’s suggestion is a good one.
However, before you drive to the mechanic–have you at least checked the transmission dipstick in order to verify whether they might be a leak? If you don’t do that first, the drive to the mechanic might kill the transmission.
I say this because of personal experience. Many years ago, while driving my '86 Taurus, I ran over some rebar rods that had must have fallen off of a truck. Because of traffic conditions, I could not stop or swerve and had to drive right over them. I did not think too much about the incident until about 10 miles further, when exiting the highway. As I slowed on the exit ramp, the transmission downshifted with great force–unlike the way that it usually worked.
I pulled over, checked the dipstick, and found that the level of fluid was very low. Since I was only about 3 blocks from my house, I drove there and called for a tow. As it turned out, one of the rebar rods had made a small puncture hole in the trans pan.
I had the pan, pan gasket and fluid replaced, and kept my fingers crossed about the future of the trans. Since I had not run it dry or driven it very far on low fluid, that transmission continued to work perfectly for the remaining 3 years that I owned the car. I lucked out, but you might not as lucky if you don’t immediately check the fluid level.
Incidentally, as luck would have it, that punctured tranny pan took place only about 2 months after I had changed the trans fluid. Talk about wasted money! However, I continued to follow the 3 yr/30k mile maintenance schedule for the trans, following the accident. That probably helped to preserve the life of the transmission.
Is it possible? Sure, but I wouldn’t say it was likely unless you had visible damage (holes, leaks, dents) in the transmission.
It might be far more of a coincidence - your generation of Accord was prone to VERY high failure rates in its transmission, particularly if you had a V6. Many of the owners with those problems complained of jerking or rough shifting…
So while it could have been the result of an impact, without other evidence, I wouldn’t rule out it just being a lousy transmission.