This weekend I fixed my non-starting truck by taking the battery out, full charging it and replacing the distributor cap and rotor. The truck has been sitting for two weeks because it wouldn't start. After taking the battery out and putting it back in the speedometer is stuck at 100 regardless of key on or off. Also, when I start the vehicle now it high idles at 1500-1800 RPM. Sometimes it will go back to normal, sometimes it won't. Is there anything I can check or fix on these two problems?

I also disconnected and reconnected the battery again to see if it would fix the speedometer. when I went to start, the fuel guage needle was upside down until I hit the dash. What is causing this?

Thanks!!!

 

Ok, update. The speedometer is fixed, but it high idles still around 2000 RPM in neutral. What can I do to fix this?

 

You need to check for vacuum leaks. Inspect all vacuum lines. Clean the throttle body, including the IAC (idle air control) valve. Clean the EGR valve. Lets see... I think that about sums it up...

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