what can couse unstable timing ? i have truble reading my timing since it keeps bouncing from 15, 13, 11, and in a blue moon 17 could a falty ACC vale be the culprit i know mine isnt work properly what else should i look at ?
btw, i have replace my dributer cap and rotor in the last 2 years, and wires and plugs

Did you unplug the TPS sensor when you were checking it? If not, you aren't going to get an accurate reading.

Curt B. Shumaker

make sure to lock the ecu in timing mode too.

My timing does the exact same thing. Starts at 15 and then jumps down to 13,11,9,7 and then back up. I was told it could be the TPS but my voltage readings are fine.

Is your idle stable?

This is common when you don't have the EGR and AIV solenoids hocked up correctly.

i think NismoSER is right. need to set the car in timing mode before setting timing. otherwise the marks will bounce around a bit.

Another vote for "you gotta put the ECU in timing mode"!

The timing will bounce all over the place otherwise and is completely normal. Don't mess with anything!