Speedometer Cable Function(s) & Cruise Ctrl
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QuickWrench
Don't Read This
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- Jan 28, 2002
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If you take off the cable, the ECM won't know the car's speed, since the speed sensor is built into the speedometer. So no, the Cruise won't work, and your torque converter lockup won't either, unless you have a manual switch. You'll get a trouble code, and your mileage may suffer a tad. Other than that, it really won't hurt anything.alphaenvirmgt said:
alphaenvirmgt said:
The cruise works off of the box under the hood where there's a speedo cable going in, and one coming out.
If you want to eliminate the upper cable that goes to the speedo head, then you need to install a *2* shutter, inline speedo sensor, and feed it's signal to the ecm (you'll probably have to do some more digging for the finite details about the wiring). www.jagsthatrun.com used to have the sensors.
Incorrect. The speed sensor is in the speedometer itself. The older cars had it under the hood. Casper's Electronics probably has what you need in order to eliminate it.bruce said:
I just noticed that your sig says FAST. If it is the older unit,then you don't have to worry about the TCC locking, since the FAST unit doesn't do this, and you also don't have to worry about setting a code, but your cruise still won't work.
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bruce, for the 86-87 the speedo cable is two peice but it doesnot have any pysical connection to the cruise servo as it did in earlier GMs ,
the cruise servo is electronic , if you loose the VSS signal and the servo has no reference to maintain speed
for the aftermarket speedos to work and maintain VSS they need to have a VSS sender installed in the speed cable (usually where the two cables join by the mastercylinder )
the stock VSS uses an optic sensor at the rear of the speedo , signal is generated by the optic sensor bouncing off a blade that spins inside the speedo head (two signals per revolution) and then the VSS buffer interperets the signals into something the ecm can use to determine speed for
converter lockup and on the stock chip for speed limit cutoff and to feed the cruise
the cruise servo is electronic , if you loose the VSS signal and the servo has no reference to maintain speed
for the aftermarket speedos to work and maintain VSS they need to have a VSS sender installed in the speed cable (usually where the two cables join by the mastercylinder )
the stock VSS uses an optic sensor at the rear of the speedo , signal is generated by the optic sensor bouncing off a blade that spins inside the speedo head (two signals per revolution) and then the VSS buffer interperets the signals into something the ecm can use to determine speed for
converter lockup and on the stock chip for speed limit cutoff and to feed the cruise
I called Caspers and they told me they have what I need (102046...VSS Convertor) so I ordered one. According to Dennis, it works in conjunction with the VDO speedometer sender. I will let everyone know if it works or not.
Conrad
Conrad
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- Aug 1, 2003
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what you said was that theres speedo cables connected to the cruise or a box of some sort . do you have a pic of this "BOX" or where it connects to the cruise in any way
theres nothing between the two cables in 86 or 87 ,
, but if you go with an aftermarket speedo that connection point is ideal for inserting a VSS sender.
on my cyberdyne dash (in the 87) to be certain there were no issues with the speed signal to the ecm I retained the stock VSS by removing the lower section of a GM speedometer (the part that contains the optic bar and allows the optic sensor to mount) and left it attached to the end of the upper speedo cable inside the car .
to drive the CYB digital speedo i had to install a cyberdyne VSS sender inbetween the upper and lower cable . the cyberdyne sender is required because the digital speedo uses more trips per revolution (8pulses) , the stock VSS with two pulses per revolution wouldnt work ,
my 86 has the PI gnx dash and it has the VDO sender(and cable assembly) attached to the lower cable (on top of fender liner) and uses its own upper cable to mechanically drive the speedo. to maintain ecm speed signal the sender is spliced into the stock VSS buffer (cut off the optic head)
theres nothing between the two cables in 86 or 87 ,
, but if you go with an aftermarket speedo that connection point is ideal for inserting a VSS sender.
on my cyberdyne dash (in the 87) to be certain there were no issues with the speed signal to the ecm I retained the stock VSS by removing the lower section of a GM speedometer (the part that contains the optic bar and allows the optic sensor to mount) and left it attached to the end of the upper speedo cable inside the car .
to drive the CYB digital speedo i had to install a cyberdyne VSS sender inbetween the upper and lower cable . the cyberdyne sender is required because the digital speedo uses more trips per revolution (8pulses) , the stock VSS with two pulses per revolution wouldnt work ,
my 86 has the PI gnx dash and it has the VDO sender(and cable assembly) attached to the lower cable (on top of fender liner) and uses its own upper cable to mechanically drive the speedo. to maintain ecm speed signal the sender is spliced into the stock VSS buffer (cut off the optic head)
If you need a speed sensor and don't have the stock dash, use Standard Motor Products SC82. It can be put right on the trans and eliminate the speedo cable or as a pass thru.
http://www.smpcorp.com/web_app/catalog/images/SC82.jpg
Mike
http://www.smpcorp.com/web_app/catalog/images/SC82.jpg
Mike
