after carb conversion no speedo
#1
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Car: 1988 Trans Am
Engine: 5.7ltr
Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
after carb conversion no speedo
Ok so I have a 1988 Trans am with a 350ci and 700r4. I did a carb conversion and now my speedo doesnt work. I haven't confirmed that I did not accidentally cut the wire to the VSS. I am just making sure that this might be an issue with removing the ECU and wiring to the computer.
Any thoughts?
Any thoughts?
#2
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Re: after carb conversion no speedo
on mine my cable goes straight from the tran to the back of the dash.
Is yours electric/digital? (sorry, I dont know much about trans am's.)
If it worked before, you need to back track and find out what you did.
Hang tight and someone will help ya.
Like sofakingdom says, The simplest explanation that fits all the facts is probably the right one.
Is yours electric/digital? (sorry, I dont know much about trans am's.)
If it worked before, you need to back track and find out what you did.
Hang tight and someone will help ya.
Like sofakingdom says, The simplest explanation that fits all the facts is probably the right one.
#3
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Car: 1988 Trans Am
Engine: 5.7ltr
Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
Re: after carb conversion no speedo
no cable on mine its electronic
#4
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Car: 91 Camaro RS T-Top
Engine: 5.0 Tbi
Transmission: 700r4
Axle/Gears: 3.42
Re: after carb conversion no speedo
There's a smaller yellow or white box next to the computer called a vss buffer box. I'm gonna guess you prolly removed it with the computer. The signal from the vss on the trans runs to the buffer box that converts it to a use able signal for the speedo read and display.
Signal goes from the sensor to the box then the box splits it into use able signal for the speedo, cruise control, and ECM. All of which use a different signal. It's basically a diverter box.
Signal goes from the sensor to the box then the box splits it into use able signal for the speedo, cruise control, and ECM. All of which use a different signal. It's basically a diverter box.
#5
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Car: 1988 Trans Am
Engine: 5.7ltr
Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
Re: after carb conversion no speedo
well crap..... is there another way to make it work? I got rid of all the stuff. I no longer have it
#6
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Car: 1988 Trans Am
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Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
Re: after carb conversion no speedo
also will it work if I was to get it back and plug it in without the ECU?
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Car: 91 Camaro RS T-Top
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Re: after carb conversion no speedo
You'd either need to get an aftermarket speed that can use direct vss signal or put the box back in. No you do not need the ecu, just the vss on trans, wiring to the box from the sensor and the one wire to the speedo.
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#8
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Car: 1988 Trans Am
Engine: 5.7ltr
Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
Re: after carb conversion no speedo
Cool so plugging the box back in using existing dash harness should do the trick then?
#10
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Car: 1988 Trans Am
Engine: 5.7ltr
Transmission: 700r4 with shiftkit
Axle/Gears: LS 4.11
Re: after carb conversion no speedo
ok so I got the VSS box back and installed it. The speedo is still not working. Any thoughts?
#12
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Car: 1988 Trans Am
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Axle/Gears: LS 4.11
#13
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Car: '88 Formula, '94 Corvette, '95 Bird
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Re: after carb conversion no speedo
Youve got wiring to do...
#14
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Car: 1988 Trans Am
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