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> TPS variations - has anyone else noticed this ?, trouble shooting and comparing 2 with same part numbers but different stop tabs etc
DRPHIL914
post Jun 8 2020, 09:52 AM
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Dr. Phil
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i will post a picture here of 2 OE TPS with part number that cross references to the 75-76 2.0 D-jet cars.

i recently pulled mine due to it bucking badly @ 2800-3400 rpm on part load or mild acceleration.
i also have one from Gatornapper to test for him and he is sorting out his D-jet parts and prepping to eventually going back from carbs to FI.
What i found was that the stop peg is located on a different place. his
essentially stops the tps from going all the way to the bottom at idle but not at the top on acceleration.
mine on the right. stops the pivot of the shaft from going all the way on the top and keeps it from being able to go off track on max, his would not.
they have the same part number. neither had been tampered with.
also i bought mine as an NOS part 7-8 years ago and now may need to be replaced.
his on the left has much more wear, actually live testing it causes same bucking but at a different lower rpm, due to wear pattern.


any thoughts? i will be putting a new board on mine as soon as it arrives
Right now i am running with it unplugged and no skip buck or hesitation now. i had been thinking it may have been an issue with my rebuilt MPS or developers valve set up or a wire shorting somewhere else, but it’s the TPS.



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bdstone914
post Jun 8 2020, 04:30 PM
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Try a pencil eraser to clean it up. If the metal is gone replace it. Shorten the pencil and put it in a cordless drill an medium speed.
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nordfisch
post Jun 11 2020, 12:10 PM
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You won't have to replace the board.

Just clean it using a fibre glass pencil. Bend the feelers just a little bit sideways so they run on fresh material. < your outer feeler seems to be misadjusted >

Don't oil or grease anything. There is so low electrical current that even WD-40 could make problems. Just clean the board and all will be fine.

---------------------------

I'm quite sure your unit is the only one that was assembled properly in the factory.
The other units will not give correct idle signal because the arm will never reach the stop-sheet. The arm turns by exactly 90° - no more. You can see the marks of the full-throttle-opening on the board - turn the arm back by 90° and the arms of both othe units will not reach the stop sheet!

Idle signal is given only when the arm reaches the stop-sheet, otherwise the signal is broken by the slide-contact located in the arm.

This misfunction (missing idle signal) will not affect any other function of the TPS.

It will only disable the function of adjusting idle CO at the ECU potentiometer and make idle adjustment more difficult.

-----------

It would be interesting to know the production code of the 3 units. The left one has the code '426' = June 1974. Nojoah's code is '329' = September 1973.

-------------------------

The production marks / numbers printed on the boards don't matter at all. They have identical design, that is what matters. Don't care about this.

Regards
Norbert
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DRPHIL914
post Jun 11 2020, 12:45 PM
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QUOTE(nordfisch @ Jun 11 2020, 02:10 PM) *

You won't have to replace the board.

Just clean it using a fibre glass pencil. Bend the feelers just a little bit sideways so they run on fresh material. < your outer feeler seems to be misadjusted >

Don't oil or grease anything. There is so low electrical current that even WD-40 could make problems. Just clean the board and all will be fine.

---------------------------

I'm quite sure your unit is the only one that was assembled properly in the factory.
The other units will not give correct idle signal because the arm will never reach the stop-sheet. The arm turns by exactly 90° - no more. You can see the marks of the full-throttle-opening on the board - turn the arm back by 90° and the arms of both othe units will not reach the stop sheet!

Idle signal is given only when the arm reaches the stop-sheet, otherwise the signal is broken by the slide-contact located in the arm.

This misfunction (missing idle signal) will not affect any other function of the TPS.

It will only disable the function of adjusting idle CO at the ECU potentiometer and make idle adjustment more difficult.

-----------

It would be interesting to know the production code of the 3 units. The left one has the code '426' = June 1974. Nojoah's code is '329' = September 1973.

-------------------------

The production marks / numbers printed on the boards don't matter at all. They have identical design, that is what matters. Don't care about this.

Regards
Norbert


231 is the number on mine, you are saying that the production date would be "72 31 week)?
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nordfisch
post Jun 11 2020, 01:23 PM
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QUOTE(DRPHIL914 @ Jun 11 2020, 07:45 PM) *


231 is the number on mine, you are saying that the production date would be "72 31 week)?

231 means November 1972

Regards
Norbert
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DRPHIL914
post Jun 11 2020, 01:30 PM
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QUOTE(nordfisch @ Jun 11 2020, 03:23 PM) *

QUOTE(DRPHIL914 @ Jun 11 2020, 07:45 PM) *


231 is the number on mine, you are saying that the production date would be "72 31 week)?

231 means November 1972

Regards
Norbert

interesting since the part number coinsides for 2.0L cars yet no 2.0's were made in 72 correct? hmmmmmm
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Posts in this topic
DRPHIL914   TPS variations - has anyone else noticed this ?   Jun 8 2020, 09:52 AM
SirAndy   The part number printed on the boards is different...   Jun 8 2020, 10:22 AM
DRPHIL914   The part number printed on the boards is differen...   Jun 8 2020, 10:26 AM
DRPHIL914   The part number printed on the boards is differen...   Jun 8 2020, 10:40 AM
Nojoah   Hmm interesting. The TPS I pulled off of my stock ...   Jun 8 2020, 10:50 AM
DRPHIL914   Hmm interesting. The TPS I pulled off of my stock...   Jun 8 2020, 12:18 PM
Nojoah   Interesting, that is really worn bad!! sa...   Jun 8 2020, 04:24 PM
bdstone914   Try a pencil eraser to clean it up. If the metal i...   Jun 8 2020, 04:30 PM
nordfisch   You won't have to replace the board. Just cle...   Jun 11 2020, 12:10 PM
DRPHIL914   You won't have to replace the board. Just cl...   Jun 11 2020, 12:45 PM
nordfisch   231 is the number on mine, you are saying that t...   Jun 11 2020, 01:23 PM
DRPHIL914   231 is the number on mine, you are saying that ...   Jun 11 2020, 01:30 PM
nordfisch   [quote name='nordfisch' post='2824128' date='Jun ...   Jun 11 2020, 02:25 PM
DRPHIL914   ok update: took advice here and i cleaned the sur...   Jun 13 2020, 02:30 PM
DRPHIL914   thought i’d post a picture after cleaning up the...   Jun 15 2020, 06:19 AM
nordfisch   Hi, the cold engine needs extra fuel AND extra air...   Jun 15 2020, 12:28 PM
DRPHIL914   Hi, the cold engine needs extra fuel AND extra ai...   Jun 16 2020, 07:23 AM
Gatornapper   Phil - "disconnecting the decel allows the r...   Jun 16 2020, 09:57 AM
JeffBowlsby   Using the decel valve is said to reduces stress on...   Jun 16 2020, 10:08 AM
DRPHIL914   Using the decel valve is said to reduces stress o...   Jun 16 2020, 10:23 AM
JeffBowlsby   "...so other than just only allowing a slig...   Jun 16 2020, 10:43 AM


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