I have a 1992 3.1 v6, and my spark timing will not advance as RPM increases. When I give it a little bit of throttle, the timing will even retard a couple of degrees, then jump way high when the engine gets to the higher revs. Is this a problem with my EST, or is something sticking? (I tried searching first, and I found something about old components sticking)

 

if the est wire has no power that is ur problem.
if it has power the wire that controls timing may have a break in it i have to look but ill be able to tell u exactly what pin is the timing control wire if u need

the reason ur timming jumps up all the sudden is because all ign moudles have a built in 10* adfvance at around 2500 rpms some have different rpm setpoints were they advance the timing automatically

 

Could somehow the connector that you disconnect to set the base timing be unplugged ?

If that connector wasn't plugged in , wouldn't that "fix" the timing at one certain point , negating the computer's advance signal , and making the spark module's on board advance at 2500 the only change in timing throughout the RPM range ?

And also , could the slight retarding of the timing with RPM increase be an indication of a worn timing chain ?

 

yes if that connector is disconected u will have 0* advance until around 2,500 rpms which would then jump up the timing 10*
the slight retard could be from timing chain slop and also slop in the distributor drive and cam gear, and also latency of the ignition moudle

 

@ init4fun
You were right. The plug was old, so I replaced the terminals, and that fixed the no advance issue.

@project 89
Thanks for telling me about that 2500 jump, I did not know that.

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If my timing chain was worn/wearing, what other symptoms, if any, would there be?

Plus, the distributor components are old, should I replace them to be on the safe side?

 

no problem man not many ppl know that the moudle has a built in 10* advance