Ka24de Intermittent misfire ANNOYING

[kyral]

Plugs are brand new, wires are new, cap and rotor are new, ignition coil is new

the big problem is its so intermittent that you could drive it for a week and it might never misfire. so when i replace anything its hard to say if that fixed the issue
Sometimes turning it on and off will buy me some time

Next move is im replacing the ignitor chip with one from the old sohc

but im starting to wonder if its my distributor itself.
I dont think its a fueling issue because my plugs looked on point ( and i have tested the fuel pressure less than 2k miles ago)
and i know its not ignition timing

[jedi03]

fuel pump or filter?

[kyral]

fuel pump or filter?

Definately not the fuel filter... those almost never cause issues and mines brand new, 2nd one since the rebuild with 2.3k miles on motor
fuel pump maybe buts its so intermittent that i cant check my fuel pressure cause it stops by the time i get home

I dont think its the igniter either, still gonna try

Im pretty sure its the distributor, it feels like its missing on just 1 cylinder when it happens, i dont know if its consistently the same one but i think it is.

[EnnEssEnnKAT]

Definately not the fuel filter... those almost never cause issues and mines brand new, 2nd one since the rebuild with 2.3k miles on motor

fuel pump maybe buts its so intermittent that i cant check my fuel pressure cause it stops by the time i get home



I dont think its the igniter either, still gonna try



Im pretty sure its the distributor, it feels like its missing on just 1 cylinder when it happens, i dont know if its consistently the same one but i think it is.

Check the ground of the coil is sufficient. That got me once

Sent from mTalk

[kyral]

Check the ground of the coil is sufficient. That got me once

Sent from mTalk
the heavily insulated black spade connector that plugs onto a male spade that bolts to the coil bracket right?

[EnnEssEnnKAT]

the heavily insulated black spade connector that plugs onto a male spade that bolts to the coil bracket right?

Yes that piece. The coil bracket must also be grounded to the chassis there i think

Sent from mTalk

[kyral]

Yes that piece. The coil bracket must also be grounded to the chassis there i think

Sent from mTalk

was your issue a very intermitent misfire? cause ive been running this setup for over 2k miles and it only recently started acting up and its very inconsistent

I ask cause i did a lot of re soldering of the harness and removing cracked and corroded wires, but before i repaired the harness i had actually used it in its poor condition and it ran the car just fine before i repaired it. so i know it can run with some heavy corrosion (injector connectors were heavily corroded and it still ran well, tho i did replace them)

that spade since its heavily insulated is quite well protected against the elements and i know mine didnt show any fatigue on the wire sheathing and there was no visible corrosion so id think that to be very unlikely but ill try and check it

[anti tyler]

You should pull off your fuel rail and see if you have a leaky injector too while you're troubleshooting.

I've experiences coil voltage drops and with good injectors you may never even notice it. BUT! with a leaky one (my situation) it will misfire as random as you're encountering.



If you have the EGR on still, that could be your issue too. As it's meant to introduce exhaust gases and produce a "controlled" misfire.

[EnnEssEnnKAT]

Leaky injector..thats a good one. Yes my issue with the coil ground caused an intermittent misfire. The ground connector that is insulated and protected there connects to that tab, which must be grounded through the coil bracket. Worth checking.

Sent from mTalk