ginahoy

I have a low-mileage 2003 Odyssey (49k) and no previous issues of any kind (save two window motors). Today as I was accelerating to reach speed on a highway, the transmission slipped and the rpm's spiked as if the gears were in neutral. Once I let up on the gas, the gears caught and I proceeded normally at my existing speed, about 50 mph. When I tried again to accelerate, again it slipped. The next time, I was able to ease up to 60 mph. Fortunately, I was just a few miles away from the house.

That's when I noticed the engine light was on. I stopped to verify the transmission fluid wasn't low, and checked the manual. It says that light indicates an issue with the emission control system. When I restarted the engine, the engine light remained on. Could this be related to the slippage or is it a bizarre coincidence?

BTW, the transmission was flushed with Honda fluid about 1,400 miles ago.

The Honda dealer is an hour away, but there's a local mechanic plus I can do some repairs myself. It would be very helpful if I could get a sense of what's likely causing the transmission slippage, and if the engine light could be related. I'd hate to have to have the car towed to the dealer.

(I previously posted this in the technical forums under the Transmission & Drivetrain but no response.)

grampswrx

That is exactly what it felt like when my tranny went out. Hopefully its something smaller like the torque converter, but its probably your transmission failing. Your local guy may be able to rebuild it, I wouldn't take it to the dealer because they will charge you through the nose. Good luck.

ginahoy

Thanks for the reply. I'll go ahead and drive it to a transmission shop. Although tranny repairs can be expensive, my immediate concern was the coinciding Malfunction Indicator Lamp (engine icon). Having read that section of the manual more carefully, it appears I overreacted to the part where it says the ECS could be damaged by driving with that light on.

ginahoy

Local transmission shop scanned for error codes. He said the Malfunction Indicator Light covers a LOT more than the emission control system, contrary to what the manual says. It scanned P0700, which is what turns on the light (A/T problem detected) and more specifically P0730 (incorrect gear ratio). He said that code means the computer module wasn't able to tell which gear is out-of-ratio. Sometimes it will provide a more specific code, such as 733. He reset the codes and suggested continuing to drive the vehicle, and if it recurs, it may provide a more specific code. The diagnostic cost $42. The service tech guessed my problem could be a bad solenoid or possibly a worn gear. Crossing my fingers.

Gearspeed-Performance

iTrader: (1)

out of ratio also means that the trans is slipping , Do you tow with your vehicle?. Worn gear will not give you an out of ratio.

ginahoy

I already knew the error was associated with slippage. He said a more specific code would have identified which gear was slipping, if I understood him correctly. I may have misunderstood regarding 'worn gear' as a possible cause. What else might cause that error? I don't have a tow hitch on the vehicle and don't carry any loads to speak of. BTW, it hasn't slipped again, although I've only driven it twice, maybe 50 miles total.

slowcivic2k

Incorrect gear ratio codes will result when the transmission speed sensors are in correct correlation, and the TCM detects slip (RPM variance) in a specific gear position. This is a mechanical problem. If it was a solenoid problem (which it almost NEVER is) you would have a shift solenoid open/short or range/performance. The TCM monitors the apply current to these devices, and if they are out of range, they will flag an electrical fault. I would ensure the fluid level after the service is correct since the driving conditions you describe would affect 2nd, 3rd, and 4th gears. This could be systemic like an oil pump failure or clogged filter.

The B7XA transmission is notorious for flaming up 2nd and 3rd gears, and ruining the reverse gear collar due to o-ring oil leakage. You unit most likely requires a rebuild. You can throw as many external parts as you want at it, and the code will still come back. Maybe not today, or tomorrow, but within 1,000 miles or so....

When DTC P0700 (GENERAL TRANS FAIL) is thrown, it is simply to illuminate the MIL.