tpastorok

So when I drive i do get a reading from the digital speedometer, but its completely wrong. If I'm going maybe 5 mph or more it will read 85.

Some facts about the car:
-Engine swapped to a v8 by previous owner
-Computer is gone
-Previous owner didnt bother to completely rewire the car, but I was able to reconnect the speed sensor
-So the wiring is kind of a mess but from what i can tell the speed sensor is hooked up right

Any information would be great!
Thanks

John in RI

iTrader: (167)

With no ECM or ECM harness in the car the digital Speedo readout should still be fully operational.

First thing I'd do is to verify what the rear end gears are. Change the rear end gear oil and look on the ring gear for the tooth count/gear ratio. Cheap maintenance and there's no guessing about the gear ratio. (If your 84 was a V8 then it should have 3.08, if it was a V6 than it should have 3.42, if stick or 3.23 if auto. )

Then I'd pull the VSS sensor from the tranny tailshaft and check to be sure the plastic Speedo DRIVE and DRIVEN gear are OK. I think your problem is here. Possible that the tranny is not original and/or the original VSS was just stuck back in without regard for the Speedo gears compatibility. ( electric VSS Speedo gears and cable Speedo gears are not the same. )

There is also a yellow plastic box under the drivers side of the dash ( could be behind the kick panel ) that's called the VSS "buffer". The Speedo signals get passed from the VSS to the buffer, then it's split out to the Cruise. Speedo and ECM. Just worth looking it over to ensure that it appears to be normal.

tpastorok

Oh that's right I forgot to mention that. The tranny is not original, so i guess that's the problem? If so where should i go from there?

John in RI

iTrader: (167)

Your probably going to need to replace the speedo gears,..... SO;

tpastorok

Okay great thank you!

dlittlefield02

I was driving and went over a bump and then both the turn signals and speedometer went out, everything else on the digital dash works though the speedometer stays at 0 and the turning signals do not activate when you flip the switch, all the fuses look good and im not quite sure what to do to fix this.

John in RI

iTrader: (167)

When a Berlinetta digital speedo shows a '0' speed when the car is driving, the problem usually isn't the cluster itself but a related item. First thing I'd check is the 2 wires plugged into the transmission tail-shaft ( to the electric VSS ) . If those 2 wires and the sensor appear to be OK than there might be a problem with the VSS Buffer at one end ( plastic yellow case under the dash ) or possibly damaged speedometer gears inside the transmission at the other end.

Ever have your tranny swapped ??