Results 1 to 5 of 5

Thread: If Not a Throttle Position Sensor What?

  1. #1
    Join Date
    Mar 2005
    Location
    NH
    Posts
    5,614
    My Cars
    E34 540i 6sp 1995-03-28

    If Not a Throttle Position Sensor What?

    After putting in a new alternator and water pump the 540 was doing fine with no evidence of any structural damage from overheating two weeks ago. No over-pressurization of the cooling system from a breach with the cylinders, no evidence of oil in coolant or coolant in oil and a smooth idle.

    Friday it was driving fine when it suddenly began hesitating. I could keep it going and it would shake a bit and then smooth out and run ok .. whenever I would change speeds there would be a hesitation upon re-acceleration but it always got going again...

    in higher gears at lower speeds shaking was more evident. I eventually when revving out of gear over 4k rpm saw a CEL blink and eventually it came on.

    A stomp test yielded 1216 Throttle Pot.

    I swapped the TPS from the secondary to the primary and placed one harvested from the secondary on my other laid up 540 that sits in a field for five years now, cleared the codes by both jumping the battery cables and holding the pedal for 10-15 sec... which gave me 1444 (clear/no codes) but the car behaves in the same way.

    I have to consider the sensor I used is also faulty and my next step will be to try a new in box sensor but if that's not it where should I look next?

    I can of course check the connector to see its voltage is constant yet I wonder if that were the cause why would it act more like the sensor just had dead spots and be able to get running ok when holding any given speed. This MAF is within the recommended replacement mileage range but I do have others I could try and see if there's a problem there but the idle is smooth.

    Really depressing after tossing nearly $1,000 to have this mystery keep me from using it.. never had a TPS issue in any of the others I've owned but time has kept marching so I hope its just the sensor.
    Last edited by jehu; 04-21-2019 at 01:40 PM.

  2. #2
    Join Date
    Jul 2007
    Location
    Oldham UK
    Posts
    3,185
    My Cars
    '00 330i Sprt '92 525i
    From the Baum Tools BMW fault code list:
    ''Damage at the throttle potentiometer connection isthe most common cause of this fault.''
    Worth a look?

  3. #3
    Join Date
    Mar 2005
    Location
    NH
    Posts
    5,614
    My Cars
    E34 540i 6sp 1995-03-28
    Replaced with another albeit used sensor and it appears to me after driving it a little shutting it off driving again that it is kind of doing the bogging and hesitating less

    is it possible that the ECU has learned and stored bad sensor data and it is being gradually replaced with a non faulty sensor now in the primary position?

  4. #4
    Join Date
    Jun 2009
    Location
    Macon, GA
    Posts
    1,224
    My Cars
    '94 530iT/A|'95 540iT/6
    I think what whiskychaser was trying to point out is that the connector and/or wiring should be looked at. Those two plugs are kind of twisted in a tight postion and it is possible that they are finally succumbing to old age. Worth a look. Only a few minutes and no cost.

  5. #5
    Join Date
    Mar 2005
    Location
    NH
    Posts
    5,614
    My Cars
    E34 540i 6sp 1995-03-28
    There's some kind of a an issue with the mobile posting and I already replied that I've examined the wires and they look fine .

    Every time I try and edit a post for spelling or what have you it just deletes it so you know I have already gone through 3 posts that I've tried to edit containing more replies along those lines.

    My greater interest would be to know if my idea about the computer writing and storing accurate information at each shut down from the now new sensor is why I'm experiencing less and less of the malfunctioning And if I should expect that as I continue to drive and the sensor is operated through its entire range in the multiple different instances the sense of provides feedback during different driving that the a preexisting faulty data will be overwritten and replaced with Accurate data
    Last edited by jehu; 04-22-2019 at 12:37 PM.

Similar Threads

  1. Throttle Position sensor can not find it replacement part
    By djchip in forum 1999 - 2006 (E46)
    Replies: 8
    Last Post: 06-19-2016, 05:48 PM
  2. Anyone have TPS (Throttle Position Sensor) issues???
    By John in Houston in forum 1992 - 1999 M3 (E36)
    Replies: 3
    Last Post: 05-05-2003, 03:07 PM
  3. FS: Bmw Throttle Position Sensor
    By AaronM3 in forum BMW Parts For Sale
    Replies: 0
    Last Post: 01-14-2003, 07:03 PM
  4. how do i know when my throttle position sensor is bad ?
    By Dj Waffelz in forum 1991 - 1999 (E36)
    Replies: 0
    Last Post: 12-24-2002, 11:12 PM
  5. throttle position sensor
    By mazen in forum 1991 - 1999 (E36)
    Replies: 2
    Last Post: 09-02-2001, 06:43 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •