Car is now bucking
 

Just after a install of analog gauges this "bucking" problem started. Almost seems as if the ecm just doesn't understand the information given to it. If the voltage or wavelength from any one of the analog gauges doesn't match up with what the ecm is looking for could this be possible?


I use the ecm from dynamic efi.

I did confirm, its the analog gauge cluster causing this problem. I hooked up my LCD display temporarily and the problem went away. The only thing I can think of is the speedometer

Not sure what you have got hooked up. Would need to know exactly what was done for a more exact opinion. But gauges are generally driven by various sensors for different indications. To affect the ECM you would have to afect an input to it, or possible load an output from it to change its proper operation.

I don't know if it is possible to disconnect the spedo to support your opinion as to what might be the problem. It may be a good starting point.