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2JZ 280 HKS cams, 1100cc IDs Rough idle and misfires.

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Hi! I need a professional advice. I have Toyota Mark 2 with 2jz-gte NON VVTi. Not my build, man come to me to fix start problems here the specs:

ProEFI 128

ID 1100 injectors

AEM IGN-1A Colis

NGK racing plugs heat range 9

280 HKS Camshafts

Ferrea valves ans springs

Titan Motorsports Cam Gears (0 on exhaust, 2.5 retard on intake)

Hypertune plenum

Hypertune throttle body

CP pistons

Carillo rods

All ProEFI Sensors

Carbonectic 3-disk clutch

The initial problem was with faulty Crank Sensor which give very weak signal

I replaced it, car starts, but idle was very rough and oscillating, I feel misfires and O2 sensor shows me 18-24 AFR on idle.

What I already done:

1) I checked compression and it was 10 in 4 cylinders and 9.8 in last 2

2) Temporary replaced plugs with ngk bkr6e-11 instead of 9

3) Tested all coils with ignition tester: https://www.menards.com/main/tools/automotive/automotive-tools-shop-equipment/performance-tool-reg-ignition-tester/w86553/p-1444447046236.htm

4) Tested coils Primary voltage drop with scope - looks ok, but see some oscillation (attached) waveform_2 is zoomed line on waveform_1

5) Removed 2 +12v wires from OEM IACV, which wasn't removed (need only H-bridges)

Next I tried to fix idle from proefi software.

1) I almost remove IACV PID reaction and leave Igniton PID (see in xcal) - this removes oscillation, caused by slow valve.

2) I strengthened ignition PID. this helps to stabilize IDLE, but with heavy misfires.

3) And finally I enrich mixture from 14.5 to 12.5 on 20-100Kpa zone

this helps to stabilize idle, and car start to react on throttle depress without trying to stop. But i don't like how car works.. If I disable Ignition PID it will oscillate from 600 to 3000 rpm. even with fixed IACV position. Looks like misfires still present.

Also it has cam gears adjustments, but I don't know why previous builder choose this values

I don't Understand what am I missing.

If needed I post VE and Spark maps

Attached Files

What is base timing set to? if the crank sensor was faulty I assuming that it was checked after being replaced but you never know

I would step warmer to BKR-7's until you get it figured out

What is idle target? 280 cam suggests it should be 1100 rpm ish?

I am not familar with ProEFI as a platform so I can't help with specifics. A log file would be better then log screenshots though

Base timing is set to 717 deg. because rear cam sensor is used for timing, but i didn't test it with the flash lamp

I replaced BKR-9 for BKR-6 for idle testing.

idle target is set to 1000

I suppose maybe some reason is in improper cam gears setup/

Never worked on those engines, but general comments.

If there's ANY misfire, it'll skew the lambda to a lean indication, even if it's a rich misfire, because it's picking up oxygen in the exhaust.

You have my sympathy trying to diagnose some else's build, but I'd start with verifying the crankshaft/piston's actual physical TDC is correctly set in the software - if it's out you're already working under a handicap. Next I'd check the camshafts were correctly timed as that can have a drastic affect on idle - retarding the intake is sometimes done to reduce overlap and dynamic compression.

With those checked, I'd suggest carefully going over the wiring and the crankshaft, and camshaft, sensor clearances and whether they are correctly identified in the s/ware.

Once you have reliable ignition you can look elsewhere - maybe an injector imbalance?

yes I see definitely misfires as AFR sometimes instead of desired 13 is 17, 22, 27 etc

CAM and CNK Sensors are ok, i checked and replaced

As figure out current cam gear position increasing valve overlap. maybe there is the reason of misfire. Now I have car out of my hands.

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