I have a 87 K5 4x4 with 350 fuel injection and 700R4.Ever since i restored my blazer about a year ago my check engine light has been coming on now for awhile and my speedometer has not worked either. I just figured the light was coming on cause my speedometer was not working. So after months of putting it off i scanned for codes and code 24 comes up, VEHICLE SPEED SENSOR.I also checked out my speedometer cable and the cable was broke at the transfer case when i took it off, so i replaced the cable and now the speedometer WORKS..but after a few minutes of driving the engine light comes back on. So i disconnected the battery for awhile (reset computer), drove it again and engine light again came back on, so i scanned for codes and still code 24 (vehicle speed sensor) comes up... does anyone know where this sensor is at?? I have checked my chiltons and haynes manual and they don't tell me anything.I called the GM dealers and one said it is on the tranny and one said it's behind the speedometer. Speedometer is cable driven so i doubt that. Any help would greatly be appreciated. thank you.