After replacing my pgm-fi relay i noticed that when the car reaches 70mph, the tachometer reads @ 2500 rpm. Prior to replacing the relay it read @ 3100 rpm. Any suggestions or I’m just reading in to much of it? Also is there a safety mechanism in the vechile if the timing belt fails?
Thank you
Automatic or manual transmission? Did you perhaps have the overdrive turned off prior to the installation of the relay?
The fuel relay should have no effect on the engine speed.
There is no safety. If the timing belt breaks the engine will suffer expensive internal damage. Don’t gamble with this.
I am not sure about the tach. There is a safety mechanism for the timing belt. The engine will cut off and you can coast to the side of the road. And enjoy the possibility that you may have also bent valves, dented a piston or 2 and maybe even damaged the cylinder head. But seriously there is no safety anything for the timing belt, the best you can do is replace on or before its scheduled time.
manual transmission
Then I can’t explain the tachometer reading.