Questions and Answers

Mazda Transmission Problem? Q. Hi Vincent, I have a 1994 Mazda 929 (3.0 liter V-6 automatic transmission) now with 100,000 miles on it. I took my car to the dealer to have a problem with the transmission at 80,000 miles. Every time I drove the car after the engine had warmed up and been driven about 8 or 10 miles, when I would slow down to about 15 mph and want to speed up again it was as if the car was still in fourth gear.

The car would bog down and the rpms would drop and the car would labor to pull itself. It would do this when going up parking ramps also or climbing small hills at low speeds, but if I was at a complete stop and accelerate the car's transmission functions normal. Same when driving on the freeway when slow down in heavy traffic and to about 15 or 20 mph and want to speed up the rpms will bog down again and labor (like I am driving a stick shift in 4th gear at 10 or 15 mph) and I will have to step on the gas hard to make the car down shift to keep moving.

Any how the dealer changed the transmission and when I drove home it did the same thing and I took back and they drove and replace that transmission out. Still did when I drove home and took back to the dealer five time to complain about the problem and they claim they can't duplicate problem. But the car in the meantime does this everyday. So in the past 20,000 miles it has had two transmissions, ECT sensor, VSS sensor, tune ups, fuel injection cleaned, timing belt changed, O2 sensor, water pump. The dealer says that no codes come up either. (I had the sensors listed changed at my own expense to try to see if they helped but not)

I noticed now that it is summer when I drive with the A/C on the car doesn't do this it is as if there is enough load on the engine to not bog down. Do you have any advice? I have now bought a new TPS but haven't had it put on yet. do you think this might be the problem. I have read some other web pages of other cars with similar problems and this was the problem even thought the car never stored any codes. Or could a clogged catalytic converter cause this problem. (Also if it was a clogged catalytic converter wouldn't I fail a California smog test?) So any help would be greatly appreciated as this car is no longer fun and laborious to drive for an automatic and I really like this car.

Thanks much...

A. Since you have had two transmissions in the car, I think it's safe to rule out the transmission as the source of the problem.

Which leaves us with a throttle valve cable not adjusted correctly or an engine control. Now I can't remember for sure, but I think the transmission gets a signal from the TPS also. So replacing the TPS could solve your problem.

If you had a clogged catalytic converter the car would barely run, if it would run at all. It is easy enough to check with a vacuum gauge.

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