Wyn
Club Member
Trying to sort out a misfire/ poor running on me 260z
Hot or cold it starts ok, ticks over reasonably well if not a little lumpy but seems acceptable
Under load in any gear it will misfire badly at approx 4.5k/5k n not rev much more
If reved at stand still it will do much the same so to me that seems more like ignition?
As the engine warms fully the misfire will happen at lower rpm. Ie 4, 3.75k, almost as if something is getting hotter and breaking down.
I changed the coil today as I had one spares but that made no odds.
Feathering the throttle at high rpm will see it rev a little more but still mis badly
Pulling the choke on seems to make no odds at all.
Turning it off when warm will result in it running on for a few secs more often then not.
Thinking its a dizzy/ ignition prob so I tried retarding and advancing the dizzy either way just to see, but it still missed just as bad at high rpm.
Had a look at the dizzy shaft n it seems the rotor arm/ spindle has excessive movement? Ie I can manually advance retard it but then it moves a little more as shown.
As far as I know its a 280zx dizzy, but are they known to break or cause like running faults if the module/ dizzy fails?
I took a short vid in the hope someone could say if it looks norm or not?
Your thoughts as I’m running out of ideas now.
Short Video Link
I don't think its fuel as surly pulling on the choke sould ease it?
Hot or cold it starts ok, ticks over reasonably well if not a little lumpy but seems acceptable
Under load in any gear it will misfire badly at approx 4.5k/5k n not rev much more
If reved at stand still it will do much the same so to me that seems more like ignition?
As the engine warms fully the misfire will happen at lower rpm. Ie 4, 3.75k, almost as if something is getting hotter and breaking down.
I changed the coil today as I had one spares but that made no odds.
Feathering the throttle at high rpm will see it rev a little more but still mis badly
Pulling the choke on seems to make no odds at all.
Turning it off when warm will result in it running on for a few secs more often then not.
Thinking its a dizzy/ ignition prob so I tried retarding and advancing the dizzy either way just to see, but it still missed just as bad at high rpm.
Had a look at the dizzy shaft n it seems the rotor arm/ spindle has excessive movement? Ie I can manually advance retard it but then it moves a little more as shown.
As far as I know its a 280zx dizzy, but are they known to break or cause like running faults if the module/ dizzy fails?
I took a short vid in the hope someone could say if it looks norm or not?
Your thoughts as I’m running out of ideas now.
Short Video Link
I don't think its fuel as surly pulling on the choke sould ease it?