Nissan 370Z Forum - View Single Post

DIGItonium · 02-26-2016, 08:28 PM

Thanks for offering to help. I got rid of Skype earlier this week. I hardly use it, and somehow my account got hijacked, and some stranger wanted to talk/spam me.

I'm using UpRev Cipher to log the data. I'm sure I can make a smoke testor using a jar, some hoses, and a small pump. Do I pull the intake filters and plug one end as I feed it? I haven't checked the exhaust manifolds since I didn't have the tools or patience to remove the heat shields. The BOV was shipped to TurboSmart for service and cleaning, and it's working just fine. The lines were fully secure as tight as possible with the zip ties. It's difficult to twist the hose. For the wastegate, I'm sure I'd notice some funky spikes under boost. It's pretty steady.

I've been hearing some "hissing" noise from the PCV with one being louder than the other, so I further tightened the hose and the noise diminished. Maybe that might help a bit.

Here's the log of the engine warming up before performing the idle relearn:
https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE

This is during the relearn, and I revved it a couple of times before shutting down:
https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE

Engine restart and let it idle for awhile to observe idle RPM:
https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE

Shut off, restart, and let it idle even longer to further warm things up:
https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE

Here's a plot of engine RPM, AFR bank 1 and 2, and coolant temp of the last log. I wanted to see how warm it usually gets before it starts acting up again. I didn't have time to drive around or run the engine, so the fans never kicked in. The next plot is just a a composite image.
https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE
https://drive.google.com/open?id=0B1...Gh2UHVHcUxaM0U

So far it appears AFR hovers around 14.5-14.8 peaking around 15 while idling. I can't tell much of a difference when it is fairly stable as it warms up and when it starts to surge between 750-900 RPM. From the plots, when the coolant temps hit 86F is when idle surge becomes slightly more noticeable. I haven't driven the car to get engine "hot" to see if it acts up again. Also, from the plots, you can see the engine slightly revving up close to 1k RPM then back to idle after starting it up. It happens as it warms up or or after a warm start.

I think I can relate to this thread:
Rough idle with forced induction

See in 1st post with video Cell posted "Bouncing idle," and that's what I'm seeing.

02-26-2016, 08:28 PM	#17 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 42	Thanks for offering to help. I got rid of Skype earlier this week. I hardly use it, and somehow my account got hijacked, and some stranger wanted to talk/spam me. I'm using UpRev Cipher to log the data. I'm sure I can make a smoke testor using a jar, some hoses, and a small pump. Do I pull the intake filters and plug one end as I feed it? I haven't checked the exhaust manifolds since I didn't have the tools or patience to remove the heat shields. The BOV was shipped to TurboSmart for service and cleaning, and it's working just fine. The lines were fully secure as tight as possible with the zip ties. It's difficult to twist the hose. For the wastegate, I'm sure I'd notice some funky spikes under boost. It's pretty steady. I've been hearing some "hissing" noise from the PCV with one being louder than the other, so I further tightened the hose and the noise diminished. Maybe that might help a bit. Here's the log of the engine warming up before performing the idle relearn: https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE This is during the relearn, and I revved it a couple of times before shutting down: https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE Engine restart and let it idle for awhile to observe idle RPM: https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE Shut off, restart, and let it idle even longer to further warm things up: https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE Here's a plot of engine RPM, AFR bank 1 and 2, and coolant temp of the last log. I wanted to see how warm it usually gets before it starts acting up again. I didn't have time to drive around or run the engine, so the fans never kicked in. The next plot is just a a composite image. https://drive.google.com/open?id=0B1...jdyNTIzdW5IQkE https://drive.google.com/open?id=0B1...Gh2UHVHcUxaM0U So far it appears AFR hovers around 14.5-14.8 peaking around 15 while idling. I can't tell much of a difference when it is fairly stable as it warms up and when it starts to surge between 750-900 RPM. From the plots, when the coolant temps hit 86F is when idle surge becomes slightly more noticeable. I haven't driven the car to get engine "hot" to see if it acts up again. Also, from the plots, you can see the engine slightly revving up close to 1k RPM then back to idle after starting it up. It happens as it warms up or or after a warm start. I think I can relate to this thread: Rough idle with forced induction See in 1st post with video Cell posted "Bouncing idle," and that's what I'm seeing. __________________ Last edited by DIGItonium; 02-26-2016 at 08:30 PM.