I have experienced shifting problems with my 2001 Honda Accord V6 transmission for a few years. It has difficulty shifting into higher gear. I have owned this car for over 19 years, and this was the only trouble I have with the car. I decided to fix the transmission or even replace it with a rebuilt transmission. I just love this car. I took the car to Airpark Auto Pros to have the work done. After having my car there for a few days, I called the shop and was told that the car needed all new engine mounts and replacing the transmission fluid. I didn't think that was the right diagnosis. The shop manager agreed to do more tests on my car. After a few days, I was told the car's catalytic converter and oxygen sensors were bad and need to be replaced and the transmission worked 100% fine. I picked up my car from Airpark Auto Pros and paid the $240 diagnosis fee. I took the car to another shop recommended by one of my friends. After a thorough test of my car, the mechanics told me the problem with my car was the transmission and he didn't even charge me for his time.
Steven, When a vehicle sometimes won't shift, or the shifts feel rough, it is entirely reasonable to assume it is the transmission. Most people would, and many shops doing a free diagnosis would probably make that same assumption. We did a deeper diagnosis, which is why you were charged for it, and we stand behind the results. We don't want to charge you for a transmission you don't need. If the powertrain control module (PCM) was commanding the transmission to shift, and the transmission failed to shift, then the transmission could have failed. However, your PCM is not commanding the transmission to shift at all. We know this because we watched the PCM data, specifically the shifting commands, and the PCM is not commanding a shift at all under moderate to heavy acceleration. In your case, the clogged catalytic converter is causing a severe reduction in engine power, which is causing you to need to press the accelerator harder. This causes the PCM to command a shift at a higher RPM. The reduced power is preventing the engine from ever reaching this RPM. That is why the transmission is not being commanded to shift and is not shifting under acceleration. The rough shifts are because the transmission is actually jerking on shifts due to the worn engine and transmission mounts. If you replace the transmission, the mounts are often replaced also, and that would resolve this part of the problem. However, it would not fix the acceleration and not shifting problem, and we would not want you to pay for a whole transmission if you only need mounts. I would suggest getting a third opinion from a high-end shop before spending money on a transmission.
- Airpark Auto Pros