Rough idle with forced induction

Mitco39 · 07-22-2014, 09:00 AM

Totally forgot to check this out for you jwick, ill do it tonight if I can remember. I am dropping my car off to get detailed this week so ill be without it most of the week.

I can tell you guys that the bad start has been fixed and it was never related to the tune, it was just a coincidence that it started to happen right around the same time. One of the wires from the fuel pump relay was coming loose from where it connects to the relay block. Got that all fixed and she starts right up just fine every time. I started 3 times back to back to back and it will good to go.

Also even driving like a toolbag at times my mileage has gone way way up after I dialed my tune in. It no longer idles or cruises rich. The hunting has almost all but stopped (still a slight hunt which I would attribute to the rerouting of the crankcase emissions system and removing it from the intake. Unfortunately there is no way to tweak the settings responsible for this. It could be the vvel doing its best to control the idle. Its minimal though compared to what it once was.

jwick · 07-25-2014, 10:28 PM

Quote:

Originally Posted by Mitco39

Totally forgot to check this out for you jwick, ill do it tonight if I can remember. I am dropping my car off to get detailed this week so ill be without it most of the week.

I can tell you guys that the bad start has been fixed and it was never related to the tune, it was just a coincidence that it started to happen right around the same time. One of the wires from the fuel pump relay was coming loose from where it connects to the relay block. Got that all fixed and she starts right up just fine every time. I started 3 times back to back to back and it will good to go.

Also even driving like a toolbag at times my mileage has gone way way up after I dialed my tune in. It no longer idles or cruises rich. The hunting has almost all but stopped (still a slight hunt which I would attribute to the rerouting of the crankcase emissions system and removing it from the intake. Unfortunately there is no way to tweak the settings responsible for this. It could be the vvel doing its best to control the idle. Its minimal though compared to what it once was.

awesome mitch. I can't wait to discuss this with tuner.

I've been thinking the crank case being directly vented instead of rerouted into the system might be causing issues too. wonder if there is any way we could find a way to rig them back in. I know the GTM kit routes them back in. I believe its pre-turbo. that would be impossible for us since the filter is directly on the turbo.

Mitco39 · 07-26-2014, 11:20 AM

Quote:

Originally Posted by jwick

awesome mitch. I can't wait to discuss this with tuner.

I've been thinking the crank case being directly vented instead of rerouted into the system might be causing issues too. wonder if there is any way we could find a way to rig them back in. I know the GTM kit routes them back in. I believe its pre-turbo. that would be impossible for us since the filter is directly on the turbo.

My car has been at a detailers all week and my cable is in the car so I havent had uprev infront of me for a bit.

But if you were going to route that vent back it would have to be under a vac only condition so you dont pressurize the crankcase more than necessary.

You could do this via a PCV valve so that when your under boost it keeps the boost out of the crankcase, but under vac it sucks in the crankcase emissions. I had it all figured out in my head last year and there is a thread that I believe I started on it. I will dig through it and see what I can come up with when I get time.

Although I personally think if we had access to the IAC tables we could tune for the idle. I also believe the VVEL does not help us. Does anyone have any experience with say sashas kit on the 350Z where the crankcase ventilation is also routed in a similar fashion?

Mitch

elperuano · 08-03-2014, 06:51 PM

Sorry if I'm asking a repeated question but is this problem only related to BP kits? Minor problem which I hope tuner could fix soon.

jwick · 08-22-2014, 07:58 AM

Mitch - Figured I would bring this thread back to life and see how things are working since it's been over a month since you made the changes to O2 sensor removal and 'cold' settings.

How's the car running? Still have any symptoms?

Ever find a fix for the hiccup or is the going theory still that the missing PCV system is causing it?

Quote:

Originally Posted by theDreamer

Check fuel & MAF readings like I mentioned in the other thread, another idea to help is if all of those with the problem could data log via Uprev the same paramters and post them. This will allow for some comparison and narrow what potential problems are causing it.

Still think it would be helpful if several of the BP guys could post log files of identical conditions (i.e. same parameters and idling conditions)

Quote:

Originally Posted by Mitco39

I think I may have found the fix today. I believe the car switches to the "cold" fuelling tables. I copied my main table into the cold (or what uprev calls cold) and it seems like its just fine now. I will have to get more seat time on it to make sure that was indeed the issue and its not just some fluke it has not came back.

Quote:

Originally Posted by Mitco39

So far so good, the lean idle has more or less stopped. But a new quirk has started which I think may be related to my changes. I been around these tuning programs long enough to realize that table names dont always mean what they suggest they should mean.

For example this car switches to that "COLD" fueling table at idle under some conditions (causing the lean spikes while idling). I would assume that that fueling table might actually not so much be a cold table as it is some sort of emissions modified table on the car. Either way changing the cold table with the main table values fixed pretty much everything. However now on hot starts it will take a second or more to crank up which also means that this car may be using this as a fueling table for starting.

My solution to this is take the cranking region of the table and return it to where it was before and see if that gives me the best of two worlds.

Either way this engine is still running strong and happy at 12-13PSI of boost.

Did the modifications to the cranking table end up fixing your hot start issues?

Quote:

Originally Posted by Mitco39

To just grab a quick log all you have to do is this (this is by memory so hopefully its a 100% correct, I dont have the cable with me currently to check it)

-Open Osiris Rom Editor
-Check for updates
-It will connect to the car and say ECU Ready after the updates are complete
-click logging and tracing
-On the right hand side of that window you will see all parameters you can select, if you happen to select to many it just wont log and you will be left scratching your head lol.
-I would like you to log the following;
-Short Term Fuel Trim Bank 1
-Short Term Fuel Trim Bank 2
-Long Term Fuel Trim Bank 1
-Long Term Fuel Trim Bank 2
-MAF flow (g/sec)
-Target AFR

Hit the red circle to record and then stop recording and save the log under file.

It will be the same ones that show up in those videos I posted last week.

The more I look at the log request list above the more I think the tuner cable provides a few more options.

Without typing them all out, pg 8 of the Cipher manual recommends the following parameters to get an eTune directly from UpRev. There are obviously some not needed (speed, coolant, speed, throttle position, etc.) but would this list provide the stuff you originally asked for?

http://uprev.com/UpdateFiles/softwar...er%20Guide.pdf

I brought this back to life because for two reasons. First, I'd really like the feedback and hopefully know if this is a good fix I should add to my next retune. Second, I kind of believe that all this still ties into my having the P2A00 code for the O2 sensor.

Mitco39 · 08-22-2014, 09:07 AM

Quote:

Originally Posted by jwick

Mitch - Figured I would bring this thread back to life and see how things are working since it's been over a month since you made the changes to O2 sensor removal and 'cold' settings.

How's the car running? Still have any symptoms?

Ever find a fix for the hiccup or is the going theory still that the missing PCV system is causing it?

The idle is much much better, it still does a bit of the hunt but its 75% better I would say. It no longer sounds like its working its a$$ off just to stay running. 0 other issues related to deleting those O2s to date.

Still think it would be helpful if several of the BP guys could post log files of identical conditions (i.e. same parameters and idling conditions)

Quote:

Originally Posted by jwick

Did the modifications to the cranking table end up fixing your hot start issues?

To be honest with you I have just been living with the hot start issue right now. But when I go and retune for these 3" charge pipes I will take a look at it. I believe its just overfuelling right now right in the cranking area. Starts great when cold, and starts fine when you turn it on after its been off for a short time. But if you let it sit and get heatsoaked she struggles at times. Im confident its just flooding itself. I also have not changed my plugs since going boosted and running sub 10:1 at times so its on the table to replace my plugs around the same time. Infact I should order up some today.

Quote:

Originally Posted by jwick

The more I look at the log request list above the more I think the tuner cable provides a few more options.

Without typing them all out, pg 8 of the Cipher manual recommends the following parameters to get an eTune directly from UpRev. There are obviously some not needed (speed, coolant, speed, throttle position, etc.) but would this list provide the stuff you originally asked for?

http://uprev.com/UpdateFiles/softwar...er%20Guide.pdf

Yes it is, sorry I never got back to you on how to get a log. I took a few screnshots and ill put them together in a mini guide for you.

Quote:

Originally Posted by jwick

I brought this back to life because for two reasons. First, I'd really like the feedback and hopefully know if this is a good fix I should add to my next retune. Second, I kind of believe that all this still ties into my having the P2A00 code for the O2 sensor.

I am pretty confident it could very well be related to your issues with that code. Reading up on it briefly its directly related to the switching of the O2 from lean to rich, which is what the car is struggling to do with those secondary 02s fighting you.

OBDII Code P2A00 - O2 Sensor Circuit Range/Performance Bank 1 Sensor 1 | Nissanhelp.com

jwick · 08-22-2014, 09:22 AM

Quote:

Originally Posted by Mitco39

Yes it is, sorry I never got back to you on how to get a log. I took a few screnshots and ill put them together in a mini guide for you.

I'll do some idle logging this weekend.

I might pull post cat sensors if I can get my tuner to update my map.

Mitco39 · 08-22-2014, 09:42 AM

Jwick,

Open up your rom editor then once its connected to the car click the logging button as shown.

Then from there you can select all the parameters you want to log. Hit record then when you are done you can stop the recording and save the log. THe log is saved in a CSV form that can be open with microsoft excel.

jwick · 08-22-2014, 09:45 AM

Quote:

Originally Posted by Mitco39

Jwick,

Open up your rom editor then once its connected to the car click the logging button as shown.

Then from there you can select all the parameters you want to log. Hit record then when you are done you can stop the recording and save the log. THe log is saved in a CSV form that can be open with microsoft excel.

Logging is not an issue. Although mine looks way different than that. It must be that I have the standard package and not tuner. I'll pull the parameters I can but I'm pretty sure 'Target AFR' is not an option on the standard cable.

nomodsjk · 08-22-2014, 09:50 AM

I'm having the same issue! This didn't start until I replaced the passenger side throttle body. I was then instructed by R/T tuning that I needed to do a throttle body relearn but I was unable to because Nissan couldn't access my ecu because of the custom tune. Well since I live 3 hours away from R/T tuning they emailed me a manual relearn process which I had Nissan do because I received the email the same day the car was in for service. When I got the car back everything seemed fine until the first attempt to turn on the AC. As soon as I flipped the switch the car started this issue and has been like that ever since. I even took it all the way back to Lansdale PA (r/t) and of course the car wasn't doing it when I was there so they were unable to fix it but the car eventually did throw a code which was for a low idle. So it's my belief that when the car went through the manual relearn process the idle was set too low but r/t disagreed. All I'm sure of is everything was fine before the relearn and now it seems like it's going to stall out at low rpm's and runs really rich at times

jwick · 08-22-2014, 09:55 AM

Quote:

Originally Posted by nomodsjk

I'm having the same issue! This didn't start until I replaced the passenger side throttle body. I was then instructed by R/T tuning that I needed to do a throttle body relearn but I was unable to because Nissan couldn't access my ecu because of the custom tune. Well since I live 3 hours away from R/T tuning they emailed me a manual relearn process which I had Nissan do because I received the email the same day the car was in for service. When I got the car back everything seemed fine until the first attempt to turn on the AC. As soon as I flipped the switch the car started this issue and has been like that ever since. I even took it all the way back to Lansdale PA (r/t) and of course the car wasn't doing it when I was there so they were unable to fix it but the car eventually did throw a code which was for a low idle. So it's my belief that when the car went through the manual relearn process the idle was set too low but r/t disagreed. All I'm sure of is everything was fine before the relearn and now it seems like it's going to stall out at low rpm's and runs really rich at times

What kit are you running?

nomodsjk · 08-22-2014, 09:59 AM

Quote:

Originally Posted by jwick

What kit are you running?

I'm all stillen. Every performance part stillen makes for a 7at 370z is on my car. Also Vince at r/t told me to clean my filters and mafs so I did and that did nothing.

jwick · 08-22-2014, 10:26 AM

Quote:

Originally Posted by nomodsjk

I'm all stillen. Every performance part stillen makes for a 7at 370z is on my car. Also Vince at r/t told me to clean my filters and mafs so I did and that did nothing.

Wonder if the issues are similar.

nomodsjk · 08-22-2014, 10:28 AM

The only thing I'm sure of is I spent too much time and money to have my car sound like its broken

jwick · 08-22-2014, 11:24 AM

Quote:

Originally Posted by nomodsjk

The only thing I'm sure of is I spent too much time and money to have my car sound like its broken

Word!

07-22-2014, 09:00 AM	#46 (permalink)
Mitco39 A True Z Fanatic Join Date: Aug 2012 Location: Edmonton Alberta Canada Posts: 2,089 Drives: 40th 370z Rep Power: 131	Totally forgot to check this out for you jwick, ill do it tonight if I can remember. I am dropping my car off to get detailed this week so ill be without it most of the week. I can tell you guys that the bad start has been fixed and it was never related to the tune, it was just a coincidence that it started to happen right around the same time. One of the wires from the fuel pump relay was coming loose from where it connects to the relay block. Got that all fixed and she starts right up just fine every time. I started 3 times back to back to back and it will good to go. Also even driving like a toolbag at times my mileage has gone way way up after I dialed my tune in. It no longer idles or cruises rich. The hunting has almost all but stopped (still a slight hunt which I would attribute to the rerouting of the crankcase emissions system and removing it from the intake. Unfortunately there is no way to tweak the settings responsible for this. It could be the vvel doing its best to control the idle. Its minimal though compared to what it once was. GaleForce likes this. __________________ 2007 Chevy Duramax - EFILive Tuned By Me 2010 40th W/ Nav - Boosted Performance - UpRev Tuned By Me The Mrs. Ride -2012 335XI N55 BMW - Cobb Tuned By Me, Built by her My Build --> http://www.the370z.com/members-370z-...39s-build.html

08-03-2014, 06:51 PM	#49 (permalink)
elperuano A True Z Fanatic Join Date: Oct 2011 Location: Southwest FL Posts: 1,374 Drives: G37S Rep Power: 28	Sorry if I'm asking a repeated question but is this problem only related to BP kits? Minor problem which I hope tuner could fix soon. JGuebara14 likes this.

08-22-2014, 09:42 AM	#53 (permalink)
Mitco39 A True Z Fanatic Join Date: Aug 2012 Location: Edmonton Alberta Canada Posts: 2,089 Drives: 40th 370z Rep Power: 131	Jwick, Open up your rom editor then once its connected to the car click the logging button as shown. Then from there you can select all the parameters you want to log. Hit record then when you are done you can stop the recording and save the log. THe log is saved in a CSV form that can be open with microsoft excel. GaleForce likes this. __________________ 2007 Chevy Duramax - EFILive Tuned By Me 2010 40th W/ Nav - Boosted Performance - UpRev Tuned By Me The Mrs. Ride -2012 335XI N55 BMW - Cobb Tuned By Me, Built by her My Build --> http://www.the370z.com/members-370z-...39s-build.html

08-22-2014, 10:28 AM	#59 (permalink)
nomodsjk Premium Member Join Date: Apr 2014 Location: martinsburg wv Posts: 2,073 Drives: 2011 370z MB/7at Rep Power: 19962	The only thing I'm sure of is I spent too much time and money to have my car sound like its broken jwick likes this.

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08-22-2014, 09:50 AM	#55 (permalink)
nomodsjk Premium Member Join Date: Apr 2014 Location: martinsburg wv Posts: 2,073 Drives: 2011 370z MB/7at Rep Power: 19962	I'm having the same issue! This didn't start until I replaced the passenger side throttle body. I was then instructed by R/T tuning that I needed to do a throttle body relearn but I was unable to because Nissan couldn't access my ecu because of the custom tune. Well since I live 3 hours away from R/T tuning they emailed me a manual relearn process which I had Nissan do because I received the email the same day the car was in for service. When I got the car back everything seemed fine until the first attempt to turn on the AC. As soon as I flipped the switch the car started this issue and has been like that ever since. I even took it all the way back to Lansdale PA (r/t) and of course the car wasn't doing it when I was there so they were unable to fix it but the car eventually did throw a code which was for a low idle. So it's my belief that when the car went through the manual relearn process the idle was set too low but r/t disagreed. All I'm sure of is everything was fine before the relearn and now it seems like it's going to stall out at low rpm's and runs really rich at times