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dakotawelch21
04-09-2018, 06:03 PM
After swapping a 1jz into my 240sx I've had issues with the motor. Compression tested fine with all cylinders around 155. Once I start it the engine will run good until it is switched over to open loop the car runs bad. When trying to rev it up there is sudden jolts of power and is not smooth at all. The idle seems a little higher and has many hiccups in it. I've already changed O2, MAP, Crank position, cam position, and throttle position sensor. None of those sensors have changed anything. Yes I did set my TPS when installing it.

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di-devol
04-10-2018, 10:08 AM
After swapping a 1jz into my 240sx I've had issues with the motor. Compression tested fine with all cylinders around 155. Once I start it the engine will run good until it is switched over to open loop the car runs bad. When trying to rev it up there is sudden jolts of power and is not smooth at all. The idle seems a little higher and has many hiccups in it. I've already changed O2, MAP, Crank position, cam position, and throttle position sensor. None of those sensors have changed anything. Yes I did set my TPS when installing it.

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Any codes? What wiring? non-vvti? ECU good?

I had a bad ecu on mine, leaky capacitors.
dakotawelch21
04-10-2018, 10:23 AM
Any codes? What wiring? non-vvti? ECU good?

I had a bad ecu on mine, leaky capacitors.No codes and I wired the motor by myself. Earley I had the car running fine so I doubt it is the wiring although it could be. It is a non-vvti. I have replaced the ecu with a buddy of mines and nothing has changed.

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coBBz
04-10-2018, 10:42 AM
Could be the igniter chip acting up, or something in your piping stopping airflow like mine was lol
dakotawelch21
04-10-2018, 11:02 AM
Could be the igniter chip acting up, or something in your piping stopping airflow like mine was lolI will check when I get home. I also have a spare ignitor that I have tried that didn't change anything.

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heywier427
04-10-2018, 11:48 AM
If you unplug the o2 sensor, does it say in open loop and run fine?

I think you meant to say, goes to closed loop.
di-devol
04-10-2018, 11:50 AM
Bad coolant sensor?

Funny you don't have any codes.
dakotawelch21
04-10-2018, 12:26 PM
If you unplug the o2 sensor, does it say in open loop and run fine?

I think you meant to say, goes to closed loop.Yes thank you I meant closed loop. I will try to unplug my O2 sensor and see what it does. Thank you guys for the input

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heywier427
04-10-2018, 01:18 PM
No codes is weird. I would think if bad coolant temp sensor, the ecu would never go into closed loop. As its not seeing that requirement set.

I know nothing about the jz. Coil / coilpacks not functioning correctly when hot?

Thats seen more on a old style coil than coil packs/plug on coil.

Does the jz ecu allow you to plug in and read realtime data?