Probleme with tach / speedo signal
#1
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Join Date: Jul 2012
Location: Jonquiere, Quebec, Canada
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Probleme with tach / speedo signal
Hi,
I put a 2008 LY5 LSX swap in my 74 nova. Everything works, except for tachometer and speedo. I have autometer electric muscle gauge tach and speedo.
I tried what i see on this forum ; pinout 48 with 1k resistance ( and put 4 cylinder / 2 pulses)..tach dont work at all ..... Really need help (e38 ecm).
Other probleme ; where i CAN find speedo signal output for my speedometer ? This the last things i need to solve to finish my car..
Thanks for your input..
Stéphane
I put a 2008 LY5 LSX swap in my 74 nova. Everything works, except for tachometer and speedo. I have autometer electric muscle gauge tach and speedo.
I tried what i see on this forum ; pinout 48 with 1k resistance ( and put 4 cylinder / 2 pulses)..tach dont work at all ..... Really need help (e38 ecm).
Other probleme ; where i CAN find speedo signal output for my speedometer ? This the last things i need to solve to finish my car..
Thanks for your input..
Stéphane
#3
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#4
TECH Resident
I pull the speed and tach signal from Gen IV L92 / 6L80 run by e38 from OBDII port via a Dakota Digital device. It was about $110. It also has an output for cruise control computer if desired.
#5
10 Second Club
iTrader: (10)
Have you checked to make sure the tach output is turned on in the ECM. If it came from a vehicle that did not have a tach is may just need to get activated. My E38 from a van was the same way.
You can get the speed from the rear speed sensor output wire. I can't help on which wire that is but you I believe you can just T off of it to get your speedo working.
You can get the speed from the rear speed sensor output wire. I can't help on which wire that is but you I believe you can just T off of it to get your speedo working.
#6
TECH Fanatic
iTrader: (19)
For the tach, send autometer tech support an email with your model number and s/n. Let them know exactly how it is wired and what it does when wired in each configuration. They will know how to convert the signal with the E38 PCM. My Ultra-Lite always shows 500rpm low when set to 6 cylinder mode.... never figured out why it does that.
For my speedo, ended up buying the GPS module for true mph no matter what gears and tires I swap around.
For my speedo, ended up buying the GPS module for true mph no matter what gears and tires I swap around.
#7
I had the same problem finding a tach signal when swapping a 5.3 into my 63 c10. If you are using Dakota digital gauges or a gauge that reads a 5v input you can tap directly into the white and black wire that goes to the crank position sensor. set up the gauge to 5v 4cyl and bam you're in there!
Hope this helps....
Hope this helps....