I am trying to get my 89 smogged and when i try and check the timing its bouncing around so i cant get a reading.

When i short out the diagnostics jumper, the engine speed does not change at all. the check engine light blinks constant, so it is in timing diag mode.

No check engine light.

Idles fine @800rpm

What should i check? what would cause this? new plugs, cap rotor, wires.

Thanks!

 

Usually means your throttle position sensor needs to be adjusted or replaced check the lce website or 4crawler webpage for great how to instructions