Q: P0730 99 Honda Accord

asked by on August 10, 2017

99 Honda Accord

The first signs of trouble was driving it on the highway for about 20 minutes and upon coming to a stop light and trying to accelerate the car wouldn't go. Shifted to natural and back to D4 tires spun but finally the car took off... let the car rest a few days and drove it literally around the corner to Orileys and got code "P0730" let the car rest again a few days around the block a few times. It again seemed to knock out off gear. When I got home I put the car into reverse and parked and cut the car off.. now when I put the car in ant gear the car just rolls backwards. I just purchased the car on last Friday. Not sure if it's worth stating but every light works except when it's in D4.
My car has an automatic transmission.

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Hi Mercedes. This is one of those very rare error codes, but when it appears, it’s typically due to internal damage or problems inside the transmission. P0730 is the OBD-II generic code for an incorrect gear ratio detected in an automatic transmission. The ratio of a combination of engine speed and throttle position and the speed of the transmission is used to determine what gear the transmission will use when driving. If there is a problem with any gear within the transmission, then the P0730 code will appear once this ratio is calculated from the sensor data in the transmission. The repairs can be as easy as adding or flushing the transmission fluid and changing the filter - all the way to needing to replace the transmission. Since replacing transmissions are very expensive, I would recommend having a professional mechanic come to your location to complete a transmission fluid flush. This may remove the obstruction in your transmission and resolve the problem. If this works - fantastic. If not, it is probably best to start looking for a replacement vehicle - as the cost of replacing the transmission is likely more than your 99 Accord is valued.

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