Hi all,

Now i cant quite remember if these stopped after i finished the engine swap, or if they stopped sometime after, i just honestly cant recall.

i swapped from a 5.0 tpi to a 5.7 tpi, which came out of the same year car, however there were some differences in the engine harness, like for the lights which were re-wired by a friend.

The stock cluster is still present behind the knight rider dash, and ive got the dash out at the minute to try and sort this out. The cluster is connected as the seatbelt light comes on with the ignition and the voltmeter works. and the corresponding gauges on the knight rider dash all work too apart from the speedo.

Then when at my yearly test i had to look up under the knight rider dash to read the mileage and it worked out i had only done 103 miles since last year ! obviously thats stopped.

Any ideas where to start looking for the problem ? im thinking its something not right between the speed sender and the stock dash

 

I can't remember what year they switched over from Mechanical to Electronic Speedo, but if it's electronic, it's possible your VSS went out or came disconnected.

 

Mine is electronic i know that much, i think they changed to that in 85 when the TPI engine first came out ?

I will check the connector on the transmission and the other end of the plug behind the distributor somewhere, i remember that from plugging it back in when doing the engine swap, im pretty sure i connected them up tightly but worth a go.

 

It was 86 when the Firebird went to a electrical gauge, and 90 when the Camaro went to an electric gauge. If I remember correctly.

 

Was under the car last night, nothing wrong with the plug in the transmission, and its connected at the other end fine.

Im wondering if there is some difference between the 5.7 and 5.0 wiring harness somewhere ? although everything else on the dash is working, just these two things.

Got a friend coming round tomorrow night who wires my knight rider dash up and he is going to have a look.

 

Most likely you have a broken or worn out gears in the speedo.

 

hoping its not that, it was working fine then both just stopped, hopefully a bad connection somewhere instead

 

Got the speedo working again ! looks like there quite a few differences between the 5.0 engine harness and the 5.7 harness because we traced the wires all the way from the sender in the transmission to where it disappears inside the car and to the yellow speed buffer box, and the wires didnt match ! so anyway i got two new wires on there and the speedo works again.

However,

The odometer still doesnt work i was hoping that would work off the same pulse as the speedo but obviously not. Does anyone know where the odomoter gets its signal from ?