Why would a 1988 Chevy Celebrity speedometer and odometer stop working and engine light blink on and off and turn off when stopped?

Answer 1

The main reason that a speedometer and odometer will stop is because the speed sensor, located on the back top area of the transmission, has gone faulty. The part can be had very easily at any auto parts store, or junkyard. The reason the check engine light is on is because the speed sensor signal goes thru the ECM (computer) for the car to run the different things. If the signal is intermitent, or interupted, the light is set, as well as the speedo and odometer not working.

Another reason is that the ECM it's self is bad, you can locate the ECM behind the glovebox and give it a few knocks while the car is running, if your engine responds by cutting out (even just a little) then replace it. they are around $110.

Since there is no speedo cable, it must be an electrical issue with a sensor.

Question

Why is there no speedometer cable? Does it have digital gauges?

The reason I ask, is, when I first got my 1986 Celebrity, the speedometer and odometer did not work. The previous owner had bought a new speed sensor, but had not had it put in yet. I installed it first thing. no luck. In checking the speedometer cable, I found it was broken, (the end of the cable at the tans-axle). After I replaced the speedometer cable, it worked fine.

Now, I cannot imaging gm did away with speedometer cables in the two years before the 1988 came out. I do have a 1990 S-15 with digital gauges, and I know it does not have a speedometer cable. But, the 1990 Sunbird I used to own, with analog gauges, did have one.