transmission issues

[puck]

I started having problems with the transmission this morning and I am curious if anyone has any thoughts before I have a transmission guy take a look at it.

The problem may have actually started 6-8 months ago. I started getting the following codes in no particular order about once every 1-2 weeks

p0120 - throttle position sensorp0732 - transmission 2nd gearp0733 - transmission 3rd gear

When the code issue first presented itself, I had my mechanic check it out. He felt is was a very common problem with the sensors in the J30 and said unless it is acting up, not to worry about. So for the last several months, I'm checked the codes as they come up and clear them. No problems at all with the way the car drives.

Today, while driving before the car had completely warmed up I had the following problems. When driving and in about 2nd or 3rd gear, upon taking my foot off the gas, the tachometer dropped suddenly to about 700 rpm and the car felt like it was in neutral. Upon pushing the accelerator, the tachometer jumped up to 3000 and you could feel the transmision catch . Only occured while moving. This occurred multiple times - 3 or 4. Once the car was completely warmed up, there was no problem - car drove completely normal.

Thoughts? Am I looking at a new transmission, new sensors or something else?


Modified by puck at 5:47 PM 9/22/2009

[yodawill2000]

Have you checked the TPS setting ??Also is the Fluid fresh or Brown ?

[puck]

fluid level is good and color looks clear and new (but it is about due for a change - last was just under 30,000 miles).

not sure what the TPS setting is? how might I check that?

btw, it has driven fine the rest of the day but threw a few more 0733 and 0732 codes.

[SKW1983]

Replace the Throttle Position Sensor.

[puck]

So I've done some reading up on the TPS here and a few other places. I think I'm having a problem measuring the voltage or I have a problem I don't understand. I've tried two different meters, measured with the car fully warmed up at idle and they are both reading from .10 to .18 volts DC. The voltage doesn't seem to vary much with an adjustment of the TPS position, but it does have a noticable effect on the idle and how it shifts/drives (as you might expect) which is why I'm thinking I'm just not measuring it correctly. I tried a new TPS and it gives the same voltages (.10 to .18 volts). I am using a bare copper wire and inserting it, as best I can tell, in the wiring harness as it is in this thread (zerothread?id=409495). My harness is different, tho, probably because it is a 97 instead of a 93.

Below should be a picture of my harness, I inserted a red wire in one picture into the slot I've mostly tried, but I've tried a few other places, including the gray harness below that one, to no avail. After some trial and error adjusting the TPS, it is driving reasonably well again but it would be nice to get this all sorted out....without a trip to the dealer, but I sense that is where this is headed.

[yodawill2000]

On my 94 the connector you test is the lower one.Both Voltage and Ohm's depending on what pins you use.

[puck]

I've tried the same hole in the lower connector, too, and get a similar voltage. I just checked again just to be sure and I'm consistently getting about .14 to .15 volts and it doesn't vary as it appears you should expect it to as you adjust the position.

I was hoping to figure out the ohm part after the voltage. For the ohm, are you measuring the same lead? what number and I hoping for?

[yodawill2000]

Its in the FSM.I'll see if I can get the pic.Pretty well documented .

[alex61089]

after getting my inhibitor switch replaced my self diagnostic decided to tell me that my throttle position sensor is bad and my revolution sensor is bad ( funny i guessed that from the start lol )It's odd though that your mechanic said that about the sensors because The car seems to be driving fine. I believe the TPS i have on there now is from pepboys, and I have one from IOS in my trunk but If the one from IOS is actually on the car there's no way it could be bad, i just got that bad boy not too long ago.