good question, and the trick is , in the spec. see it says hot normal idle which is 800, and if idle is bad, the freeze fails. as does hot, and all these.
the FSM does not cover these.... (partial)
see freeze fail here
http://www.fixkick.com/IGN_timing/IGN-FREEZE.HTML
see all 10 ways.
im sure there are others,.... I think they do this to cut smog if you leave the jumper there... and cat burn out. in 1996 it throws a code, jumper left in error.
i see you are checking it close.
no freeze jumped, the timing can bounce like crazy hot 800..
this is normal, if it dont, id expect the TPS switch is not closed, does the FAN and Head lights turn on
together (nofreeze) keep the idle steady, at 800 rpm. and not slow down, (dead ISC)?
the Cel will glow if the idle switch fails , (it watches RPM and map to see if switch (idle) is incongruent or contradictory.)
eg max air flow an switch closed? or rpm 800 all the time but switch not closed. and 19inchs vacuum (idle)
it might be the ecu and closed loop is so good, it dont need to play with idle timing. possible?
I always thought the timing bounces as a result of the 02 swings. the hunting of it. lean, rich,lean rich and as it did that, the ECU made minor timing tweaks to make it even more better.
all theory that...
trouble is , the 91s we can not see closed loop directly. (no scan tool) if i saw it out of closed loop CL, id be fixing that first. at idle and light cruise.
the FSM does not cover these.... (partial)
see freeze fail here
http://www.fixkick.com/IGN_timing/IGN-FREEZE.HTML
see all 10 ways.
im sure there are others,.... I think they do this to cut smog if you leave the jumper there... and cat burn out. in 1996 it throws a code, jumper left in error.
i see you are checking it close.
no freeze jumped, the timing can bounce like crazy hot 800..
this is normal, if it dont, id expect the TPS switch is not closed, does the FAN and Head lights turn on
together (nofreeze) keep the idle steady, at 800 rpm. and not slow down, (dead ISC)?
the Cel will glow if the idle switch fails , (it watches RPM and map to see if switch (idle) is incongruent or contradictory.)
eg max air flow an switch closed? or rpm 800 all the time but switch not closed. and 19inchs vacuum (idle)
it might be the ecu and closed loop is so good, it dont need to play with idle timing. possible?
I always thought the timing bounces as a result of the 02 swings. the hunting of it. lean, rich,lean rich and as it did that, the ECU made minor timing tweaks to make it even more better.
all theory that...
trouble is , the 91s we can not see closed loop directly. (no scan tool) if i saw it out of closed loop CL, id be fixing that first. at idle and light cruise.
http://www.fixkick.com