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Wot Causes A Cylinder To Drop?

boosted_32

By boosted_32,
in Engines & Forced Induction

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boosted_32 Proficient

boosted_32

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hi guys was driving my car 2day then then all of a sudden its lost alot of power and sounded like a wrx. I have a 32 with a rb26, I took it to a mechanic to have a look at it, Had about 10 grand spent on the motor 6 months ago so I was very worried something had happend, they guy did a compression test and everything seems to be fine 150psi across all 6 cylinders and plugs seem to look ok aswell? wot else could cause a cylinder to drop out? its cylinder 1. I have just put new splitfire coils in it aswell so I can eliminate that and It did have new plugs put it it last oil change

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QWK32 Veteran

QWK32

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could be an injector, coil, or the ignitor pack, the wiring to the ignitor pack, the wiring from the ignitor to the coil, the wiring to the injector, it even could be the cas.

start with, pulling the coil out of cylinder 1 and swapped it for say cylinder 2, if the problem moves to cylinder 2 then its the coil. if it stays on cylinder 1 then its something else.

then i'd checked the injector is getting its pulse, is it squirting fuel. if it is its probably the ignitor or cylinder 1's ignition wiring. if not then id check the cas out.

boosted_32 Proficient

boosted_32

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could be an injector, coil, or the ignitor pack, the wiring to the ignitor pack, the wiring from the ignitor to the coil, the wiring to the injector, it even could be the cas.

start with, pulling the coil out of cylinder 1 and swapped it for say cylinder 2, if the problem moves to cylinder 2 then its the coil. if it stays on cylinder 1 then its something else.

then i'd checked the injector is getting its pulse, is it squirting fuel. if it is its probably the ignitor or cylinder 1's ignition wiring. if not then id check the cas out.

hey mate found the problem but dont know where to start to fix it, we took the plug of the injector for cylinder one and put a test light on it and you can see the light flashing on and off as the injector is pulsing but then all of a sudden it stops for a bit then comes back on and keeps doing it, so every time it looses power I drop cylinder 1???

QWK32 Veteran

QWK32

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when you say your watching the injector test light flash, then stop for abit, are you just watching this while your cranking the engine, or when the engine is running?

what ecu are you running?

and did you check the condition of the wires and plug for that injector?

boosted_32 Proficient

boosted_32

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when you say your watching the injector test light flash, then stop for abit, are you just watching this while your cranking the engine, or when the engine is running?

what ecu are you running?

and did you check the condition of the wires and plug for that injector?

yeh had the engine running and took off the injector plug to test it with a test light and the light pulses as its ment to but then cuts out for say 30 sec or a couple of mins then comes back on......keeps doin this. Im running an emanage piggy back

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