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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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nordfisch
post Jun 15 2020, 12:28 PM
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Hi,
the cold engine needs extra fuel AND extra air.
Seems the AAV doesn't open enough in cold state.

Regards
Norbert
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DRPHIL914
post Jun 16 2020, 07:23 AM
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QUOTE(nordfisch @ Jun 15 2020, 02:28 PM) *

Hi,
the cold engine needs extra fuel AND extra air.
Seems the AAV doesn't open enough in cold state.

Regards
Norbert


I appreciate the suggestion, I checked this last night, appears full open and closes up as well, other thought was the CHT resistance at cold, this seems to be off, I added an adjustable rheostat goes from 5-500ohms, to the cht line just to see if that helps, and it does bring cold start up idle up some, then once warmed up fully , idle air valve closes and the idle comes back down to a proper 900, might try a different new 012 cht from 914rubber tonight too, but the extra resistance did the trick.

the other issue was that on acceleration it was very slow to return back to idle even with me manually operating the accel cable at the throttle body, and quickly closing it, so I looked closer at the decal valve, which I recall I ddint have this issue until installing that. disconnecting the decal allows the rpms to return back quickly to normal not hang up and "lag" . not sure what the d-jet experts make of this but with out the decal hooked up all seems better.

will keep playing around with this, but I cn tell you I had it hooked up according to the pictures I had for this.

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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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