Speedometer jumping

1994 ACURA INTEGRA
157,673 MILES • 1.8L • 4 CYL • 2WD • MANUAL
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MRMARKD
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My VSS is reading 9.4v on the pulse wire, 12.44v on center wire, .02v on ground.
I get the 9.4v reading at the ecu, gauge cluster, and VSS itself. No blown fuses. it is a chipped p28, 94 integra GSR B18C1
Any information would be helpful as I have read what seems like a book of threads from different forums and no one has had this issue...

I've used 2 different clusters, 2 different VSS.
Cleaned all grounds and in some cases moved to new locations. TPS reads fine.
also no check engine light.

Parts list if needed..
Header to APEXi muffler (2 1/2in)
CAI
SKUNK2 ALPHA RAD
SKUNK2 PRO SERIES 74mm tb & im
AEM high flow fuel rail
AEM fpr
Walboro 255 high pressure fuel pump
Chipped and dyno tuned obd1 ecu
Rywire b series tuck harness
Mishimoto 68°C thermostat

Almost every sensor has been replaced in the past few months.

Thanks in advance.
Sep 2, 2019 at 3:24 PM
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STRAILER
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Hello,

This sounds like the ECU is bad causing the speedometer operation you have described. Here is the location i would try a used unit or rebuilt. Check out the diagrams (below). Please let us know what happens.
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Sep 4, 2019 at 10:43 AM
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MRMARKD
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I was thinking that too, I'll see if I can find my p72-a01.
Sep 4, 2019 at 11:30 AM
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STRAILER
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Please do and let me know.
Sep 5, 2019 at 11:25 AM
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MRMARKD
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Did not work. Check engine light came on, but when I tried to check it it was gone.
Sep 5, 2019 at 12:30 PM
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STRAILER
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Not sure what you are saying here.
Sep 5, 2019 at 1:16 PM
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MRMARKD
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Tried a different ECU no change in speedometer working... it did throw a check engine light, but when I turned the car off and then to koeo no codes flashed.
Yes, I had a clip in the blue code plug passenger side.
I've also checked the harness and have continuity with all 3 wires.
Sep 5, 2019 at 2:24 PM
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MRMARKD
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I'm getting a straight 9.48v on pulse wire in koeo, with koer I'm getting 10.44v no pulse whatsoever in or out of gear...
Sep 5, 2019 at 6:16 PM
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STRAILER
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It could be an ignition feedback issue. do you have good quality (new) ignition parts? Here is a guide to help us check the wiring and the cluster wiring diagrams below:

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Please let us know what happens.
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Sep 7, 2019 at 12:12 PM
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MRMARKD
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Thanks for the diagrams and sorry I didn't write yesterday, but I have already found the problem and have corrected the situation Friday afternoon. It was in the harness itself. the plug had actually shorted even though I was getting continuity; it was shorting when energized.
Sep 7, 2019 at 6:39 PM
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STRAILER
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Glad you could get it fixed, that kind of problem can be tough. Please use 2CarPros anytime we are here to help.
Sep 9, 2019 at 10:38 AM
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GODSOL
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I recently purchased my 1994 Acura Integra LS (automatic). I tested it 20 different times with another car driving next to me, and we figured out that my car is off by around 8-10 MPH. And that's the Speedometer saying it is 8-10 MPH *faster* than what I'm actually driving at. So I was wondering how and where to go to get it fixed. Thanks in advance! ;)
Sep 9, 2019 at 10:38 AM (Merged)
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F4I_GUY
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Sometimes you can't do anything about it.

However some things to check:
Ensure you have the PROPER size rims and tires on the vehicle that come recommended from the factory. Ensure the tire pressures are set at the proper psi.

If you have factory sized wheels on, then I would personally check your VSS (vehicle speed sensor). If that's fine, you may need to replace the speedometer section of the cluster.
Sep 9, 2019 at 10:38 AM (Merged)
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MRMIKEY05
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Hi, I owned a Acura Integra GS 1990. One night I was driving my car at 65 mph and the M.P.H drop all the way to 0. Everything else work. The next day I took out the cluster to check up on the speedometer cable and I found out that it snap at the square end. What should I do to repair this? I do not know how to change this cable because I do no even know where it goes behind the dash. What should I do?
Sep 9, 2019 at 10:38 AM (Merged)
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2CARPRO JACK
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You have the instrument cluster out? Be sue th espeedo head (gauge) turns freely and didnt cause the break. If ok, then go to Acura and buy the cable without the housing and pull it out of the housing. It goes to the speedo drive on the transaxle. Slide the new cable in with a little grease on it to keep it from chirping
Sep 9, 2019 at 10:38 AM (Merged)
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MRMIKEY05
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Thank you for your reply, I will do that.
Sep 9, 2019 at 10:38 AM (Merged)