I had a slipping tranny - it would slip right at 30mph, right as it shifted into third. It would shift into third and then slip back into second. Very scary and annoying.

I did some research and, long story short, the problem was entirely solved by simply replacing the Throttle Position Sensor. The part cost me $70.

I'm not saying it will work for you, but I'm saying it's worth checking out.

As I was switching the parts out I decided to do a resistance test on both the new and old parts. The resistance of the old, defective, part was only a little bit off from the new one, and (if I remember correctly) still within working specifications.

But the tranny problem was completely solved when I replaced the TPS.

 

Wow! I never would have thought of that! But it makes sense. The throttle position indicates what the driver wants to do. If that signal is wrong the shifting will feel strange to the driver, but completely logical by the computer.

 

This is just like on the older cars that had kickdown cables/rods and vacuum modulators, thats how the tranny "sees" what the driver wants, anything that messes with driver input messes with everything.

 

so yeah you guys think i should purchase a tps, ive seen one for 34.99 at my local auto part store? also where would the tps be on a 1.8 liter, i dont really know other that it's on or around the throttle body. Other than that the other day my shock absorber mount broke, so i just got that replaced today only $122

 

No.
We guys think you should take out the existing TPS and test it with a voltmeter. If it is good put it back in place and look further.
While you are there give the throttle body a good cleaning with CRC throttle body cleaner.
And get the Haynes manual, otherwise we would have to retype it here in sections.

Youtube is full with how to videos on various procedures.

 

Good throttle body cleaning video: Rough Idling Issues | MotorWeek
Clean your MAF while you're there as well.

 

i cleaned the throttle plate maybe last month and also when i replaced the intake manifold i cleaned out the sensor no change, od light still blinking so as soon as this car breaks down im going to look around for car around
$7000, where would the tps be located on a 1,8 liter

 

Mr. dblanco:

This question "where would the tps be located on a 1,8 liter " really tells me that you are not comfortable finding your way under the hood. I suggest you get the Haynes manual (about 20 USD at any parts store) and get this for any car you own.

The Throttle position sensor sits on the throttle body with electrical wires attached to it.
It looks a little like this:


And richpin on Youtube has a nice video on how to test it. Soo, it's on a Saturn.

 

How to Test Sensor: Replace TPS: I do lots of research fro an aftermarket company!

 

hey guys sorry late update, so i took to a mister transmission here in Toronto, and He took a look and suggested a rebuilt since it was throwing a p0730 code( incorrect gear ratio) but after that i had a look at this website which suggested upgrading my pcm to a newer type so it can read the right code
Protegé FAQ - TSB 05-002/00

so guys i was wondering, because i found the same number pcm for $130. I just wanted to know if like would i have to have it reprogrammed or can i just plug it in before wasting money