1jz constant miss

[chris davey]

Waste spark setup on 1jz. Car wasn't driven for about 3 weeks. Started it up and it is running on 5 cylinders. Pulled coil leads off until the engine tone didn't change and determined that it was cylinder 2 that was missing.

So first up checked the power and ground wire going to the coil. I don't have a scope. I checked for voltage in both and they both show 11v with the ignition on but car not running. I didn't try it with the car running.

So I swapped to a different set of coils packs. Started her up and it is still missing.

Pulled the plug out and it was very black which is to be expected if it is missing. gave it a clean and chucked it back in. Still missing like crazy.

This is from idle and at any tps up to about 3000rpm is all I have gone to.

Car is waste spark and cyl 5 is ok so it is cyl 2 not the pair of them. (as they are signalled by the same channel on the bosch igniter)

thoughts?

[oldcorollas]

swapped leads? cracked plug? faulty injector?

[1JZ~lux]

If you've checked everything on the ignition side of it, then I'd be looking at the fuel side. Maybe a blocked injector or the power/signal to the injector.

[chris davey]

the plug was covered in fuel so I think the injectors are fine.

no leads

I will try another plug and see how that goes.

[oldcorollas]

oh, i must have misread the "Pulled coil leads off until the engine" heh heh

plug covered in fuel could also be injector sticking open and drowning the spark....maybe?

[The Real Roadrunner]

new plugs should fix it, plugs dont like being fouled and generally wont completely recover.
also be sure to crank it with the CAS unplugged so it gets the leftover fuel out of the cylinder.

cheers
linden

[Pure_In_Sanity]

Chris, i had the exact same problem with my 1jz when first started. ( Had been sitting around for a LOT longer though )

No. 2 constant miss, plug wet, swapped coils etc all ok.

Turned out to be the injector sticking open & flooding the cylinder.
Fix.. was desperate, wired injector to B+ for long enough to warm it up a little. Then toggled it several times & it hasn't missed a beat ever since.

(cambelt1 put me onto this, i was amazed after it worked!)

Cheers
Phil

[chris davey]

thanks people, will try some stuff out tomorrow

[manny]

If fuel and spark are ok, look for a valve stuck open - a comp test will eliminate/confirm.

[SillyCarS]

i have heard of injectors sticking after they have been sitting for ages, i reckon its something my 1g will definately suffer from

linden. waht is the CAS? do you mean crank it with the plug out?

[Rossco]

use brand new plugs, i had the very same problem, cleaned plugs didnt do shit, brand newies fixed its up pronto

[Gavatron]

linden. waht is the CAS? do you mean crank it with the plug out?

Crank Angle Sensor. So no fuel is injected as the ECU won't know that the engine is cranking.

[SillyCarS]

neat trick

[Pure_In_Sanity]

How did you go Chris?

[chris davey]

changed to a new bkr7e and it is much better.

thinking i will swap to bkr6e's as it is only running low boost and should help burn better when engine is cold and it is running rich.