Rb20 Missing On Cylinder 4

[carl h]

heres the situation...

rb20 using a 25 pfc, drove the car up to school and it was flawless parked it over night went to go to the store and found cylinder 4 had mysteriously stopped firing.

plug was drenched in fuel and pulling the injector clip while it was running made no change in engine speed/sound.

swapped ignitor out with 2x spares as well as my known good stock coils, still nothing.

continuity tested the coil harness and it appears to be fine as well.

HELP!

Edited August 18, 2007 by carl h

[sky_2.0T]

heres the situation...

rb20 using a 25 pfc, drove the car up to school and it was flawless parked it over night went to go to the store and found cylinder 4 had mysteriously stopped firing.

plug was drenched in fuel and pulling the injector clip while it was running made no change in engine speed/sound.

swapped ignitor out with 2x spares as well as my known good stock coils, still nothing.

continuity tested the coil harness and it appears to be fine as well.

HELP!

check compression ,swap ecus

[carl h]

compression was checked not too long ago, motor was rebuilt approx 6 months ago...

starting to lean twards stuck injector.

[blind_elk]

check compression ,swap ecus

The coils would still fire with less than optimal compression.

carl, so you've tried a different coilpack in #4. And you've tried swapping that coil to another cylinder? It sounds like the circuit in the PFC has crapped its pants. Don't ask me why, though.

[paulr33]

hi carl

when you made the 25 PFC work on your 20 how did you manage the injector flip

was it hardwired? solder change? board change inside? this could be a hint, maybe a connection has come loose

[carl h]

injector driver swapping was easy as, just remove the pins from the ecu connector and swap...

gonna test for spark today and if i have spark then fingers start to point at the fuel system.

as far as the pfc being damage, i dont believe that is the problem...i opened up the pfc and inspected it and there were no signs of burnt traces or the scent of a toasty ecu.

Edited August 19, 2007 by carl h

[carl h]

still no spark and all out of ideas.

ive tested coil, ignitor, ecu harness...not sure what else to try.

any ideas?

would a bad coil harness do this?

[r33_racer]

apparently the ignition loom can go shitty from the heat, could be worth a shot if you have another lying around somewhere. Quick change over to prove or disprove that idea.

[Fixxxer]

You have tested with another spark plug right?

Fixxxer

[carl h]

new plugs all around still the same result even the good old screwdriver in the coil pack against ground didnt work.