Misfire 172 tried lots Still There !!

[KLUNK]

is the ignition system a wasted spark system ?

if so wouldn't that mean cylinders 1+4 and 2+3 would go out simultaneously?

the fault was originally on 2+3, when it followed the injectors to 1+4 i mistakenly thought the injectors were out, but if it's the 'triggers' to the coil then could it be that both triggers are suspect and at any given time one of them is playing up, giving the impression of the fault moving?

anyone know hoe i would check for this?

there is no obvious damage to the coil wiring plug or the ecu wiring plug.

where is the engine earth strap?

 

[MicKPM]

Yep, its a DIS "waste spark" ignition system but not injection as this is sequential - The coil drivers fire in banks hence the "waste" of a spark but the injectors 1-4 & 2-3 don't fire at the same time as that wastes fuel and could cause other issues such as DET and bore-wash. It is getting to the point though where internet diagnosis is going to become difficult and it needs a keen/trained eye casting over it. Even a session on an Oscillescope will confirm/deny the ignition/injector drivers are functioning okay.

Mick

 

[jack_davey]

Sounds like a wiring fault to me, if you're intent on fixing it yourself, get a wiring diagram and check for continuity and high resistance on the ECU wiring loom.

 

[Sparko]

Plus 1 for investigating fuel system.. You could remove the pump and hook it up to a battery pack to test the motor. I know its a very basic check but you could check the filter isnt clogged too..

 

[KLUNK]

update,

i have cleaned all the sockets and pins on the ecu, injectors and coil that deal with injector and ignition signals

tested the resistance using a proper multimeter and they we all 0.1 to 0.2 ohms

cleared the ecu faults (still only showing coil fault and multiple misfire)

ran the car for 30 miles over about an hour, not a cough or slightest misfire in fact it has never run so smooth.

idle once up to temperature was buttery smooth and almost silent, it's never been like that in the two and a half years i've had the car.

i still havemnt; checked compression or fuel pressure , but in my view nothing points to that...

with the faults always being a miss on 1and 4 or 2 and 3 which coincides with the coil and trigger lines from the ecu, and the ecu fault codes being the same this could be it .

fingers crossed.

for those who have searched and found this thread with similar issues, if the thread has died then this was the issue !!

 

[dorian]

Hello mate. Did u sort it out? If not may I suggest the following
If u changed plugs, leads and coil. Do this, remove the cover of the ecm connector. Engine on wiggle the coil control wires and check if it starts to misfire . If u dont have the pin-out of the ecm give me ur email and i will send it to u. This happened to me and since I dont have much spare time I had to take it to a mechanic which gave me a quote of 400USD aprox worth of parts and labor!!!! I checked it myself when I had the chance and found that the coil control wire to cylinders 1&4 (pin 32) was loose!!! that was it!!!now I have 500km running great since the repair. Let me know if this helps. Regards