Transmission Problem
 

Over the past month my car has been slipping out of gear when driving with the transmission in drive. It just downshifts to 3rd for a second and then goes back to 4th every so often. Recently it has been goin from 4th all the way down to 2nd every a few seconds. It also does it in every gear except 1st. However, it doesnt slip out of gear at all when in manual mode. I've taken off my tps sensor thinking it was that and tested it. I took the spring off the sensor so it wouldnt give any resistance when I tested it with an ohm meter. Where ever the tps sensor is set it constantly fluctuates. I tried cleaning it out with electronic cleaner and puting it back on my car and properly adjusting it to 0.50 volts when throttle closed but it still slips out of gear every few sec without the manual mode. I was just checking with you guys to get your opinion before I go out and spend the money on one. Thanks

Jason

Gid'ay Jason, the throttle sensor is the cheaper of the two likely causes. As you say," Where ever the tps sensor is set it constantly fluctuates.", if there is wear on the track of the sensor, it can cause this to happen.

The other option is of course, the high clutch, but you say "It also does it in every gear except 1st.". So if it does it to 2nd gear also, it won't be the high clutch.

Back to you to see which of the two it is. The high clutch is only active in 3rd and 4th, if it is confined to just these two gears, it can be the clutch, but if it does it in 2nd also, it is the throttle sensor.:)

Harvey.;)

Hi jason,

I am not quite sure what you mean by " I took the spring off the sensor so it wouldnt give any resistance ". Have you referred to my write up in the how too section? If not please go there.

You say, " I tested it with an ohm meter. Where ever the tps sensor is set it constantly fluctuates." This indicates intermittent contact. The resistance element comprises conductive plastic. It is difficult to get any cleaning fluid inside to the moving contact and element. You must try and penetrate by way of what openings are available; not easy. Work the rotor at the same time.

You should get a smooth change in resistance as the mechanism rotates. If not there is a fault. What is more an ohm meter check is not absolutely reliable because the reading is not instantaneous as you wound record with an oscilloscope, but it is still worthwhile.

After a further investigation, report back if you require any further help.

Cheers, Trevor.

When I said I took the spring off the tps sensor, I meant the one on the sensor that always turns it back to the throttle closed position. When I was bench testing it, I didnt want any restrictions so I took it off. That way I could set it and it would stay at that exact position. Anyway, I have come to the conclusion that it is in fact worn out and ordered a new one. It should be here in a few days. Thanks

Jason

Good one Jason. It is apparent that you know what you are about and have come to a sound logical conclusion. Only by way of a reminder, as i am sure you have this in mind. Make sure you take a voltage measurement and set the new component correctly, when you install it. :cool:

Thanks for all the help guys. I recieved my sensor last friday and installed it over the weekend. It adjusted nicely and i've driven about 300 miles and it hasn't slipped out of gear once.

Jason

good to hear. Saved yourself a lot of money by getting a TPS and not automatically going for the tranny

Tom