Gas Pedal Delay

wstar · 08-02-2012, 08:26 PM

Well the AT's first gear comes out at a lower ratio than the MT's, even given the worse ratio in the final drive. That's probably most of it. The lockup torque convertor works great, so you don't see as much slippage loss as traditional ATs. And of course 7ATs have the torque multiplication factor going for them too when you first engage.

IcedZ · 08-03-2012, 09:25 AM

Quote:

Originally Posted by kenny's 370z

interesting link here.from my understanding of how the vvel works,it is my assumption that in the higher rpm band,the intake valves are letting more blowback in via higher valve lift vs lower rpm band via lower valve lift.could this be the culprit ? letting too much blowback in ?
Nissan Introduces New Engine Valve Control Technology - Variable Valve Event & Lift (VVEL)

I've been suspecting something to do with this, but it isn't all the time which leads me to believe some sensor is malfunctioning under certain conditions, causing erroneous data to be input to the computer.

kenny's 370z · 08-03-2012, 10:27 AM

Quote:

Originally Posted by IcedZ

I've been suspecting something to do with this, but it isn't all the time which leads me to believe some sensor is malfunctioning under certain conditions, causing erroneous data to be input to the computer.

i agree.this morning my car was losing alot of power and what seemed to be missing like i was running on 4 plugs periodically.maybe in my case,its the cats.this is twice now since ive owned it that this has happened.

tb grounds are coming back off today.last time i ran the car it was 95 with a heat index of 102.this morning it was 75 degrees.is it possible to run the car with vvel unplugged for testing purposes ?

what about the people that run test pipes,do they have this problem also ? i want to try an eliminate troubleshooting the 02's before i waste my time unhooking the exhaust to have a look at the cats

wstar · 08-03-2012, 11:20 AM

The only sane way to disable VVEL is to replace the heads. VVEL is an oil-pressure-driven mechanical system with an eccentric shaft, etc. The electronic servo just controls the angle between the shafts. Somehow disabling the ECU's control of it would probably be catastrophic.

Have you gone over all the basic maintenance/inspection stuff? PCV system, air filters (not clogged, not leaking air around them from a bad seal, etc?), clean the MAF sensors, reset the idle air volume, check for exhaust / intake tract leaks, etc. There are a lot of "little" things that can adversely affect engine performance.

kenny's 370z · 08-03-2012, 12:03 PM

the only thing i havnt done yet is to replace the spark plugs.

edit;on lunch today,i took the grounds back off the throttle bodies and i believe the grounds were hurting more than helping.this car is like a woman.moody as hell lol

Compdoc777 · 08-03-2012, 01:13 PM

Quote:

Originally Posted by wstar

The only sane way to disable VVEL is to replace the heads. VVEL is an oil-pressure-driven mechanical system with an eccentric shaft, etc. The electronic servo just controls the angle between the shafts. Somehow disabling the ECU's control of it would probably be catastrophic.

Have you gone over all the basic maintenance/inspection stuff? PCV system, air filters (not clogged, not leaking air around them from a bad seal, etc?), clean the MAF sensors, reset the idle air volume, check for exhaust / intake tract leaks, etc. There are a lot of "little" things that can adversely affect engine performance.

You can control when the VVEL kicks at what rpm. That will affect fuel efficiency, but give you more power lower in the band.

DIGItonium · 08-03-2012, 03:33 PM

Quote:

Originally Posted by kenny's 370z

edit;on lunch today,i took the grounds back off the throttle bodies and i believe the grounds were hurting more than helping.this car is like a woman.moody as hell lol

Your car may have cooled down with the time taken to remove the ground connections.

Quote:

Originally Posted by Compdoc777

You can control when the VVEL kicks at what rpm. That will affect fuel efficiency, but give you more power lower in the band.

Not sure what you mean here. VVEL is always active. It's the sole mechanism for controlling throttle. The butterflies are still there, but are always open.

wstar · 08-03-2012, 06:36 PM

^ VVEL is always active, it's pretty integral to how the ECU operates this engine (VVEL != VTEC). I'm pretty sure the normal throttle butterflies *do* vary in some situations though, they're not completely static.

kenny's 370z · 08-03-2012, 10:20 PM

i took that sensor out that is connected to the vvel motor that goes in the top back side of the im.it was oily.not dripping, but oily.so when you clean the maf sensors,hit that one too.

i also found this interesting;
http://www.allanglesdesign.com/porta.../CCV_Bible.pdf

wstar · 08-04-2012, 12:18 AM

I really like that PDF, good explanations I haven't seen elsewhere. Currently my car is in his "Stage 1" config. I have a really good quality baffled can on the PCV side, and stock hose on the fresh air side. (Well, our car has two of each of those lines, and I've run my PCV lines together with a Y-adaptor for a single can).

It's tempting to go ahead and run dual cans with his stage 3 setup for the NA 370Z, and I might get around to that someday. You could use the existing fresh air paths since we already have two of them, just replace those plastic baffled things with regular hose through cans, and then cap off the PCV valves and corresponding manifold connections.

IcedZ · 08-04-2012, 01:52 AM

Quote:

Originally Posted by kenny's 370z

i took that sensor out that is connected to the vvel motor that goes in the top back side of the im.it was oily.not dripping, but oily.so when you clean the maf sensors,hit that one too.

Interesting.. I never looked at that. Did it make any difference?

wstar · 08-04-2012, 04:03 AM

It could be that it lives in the flow of oil and is always oily

Compdoc777 · 08-04-2012, 08:59 AM

Quote:

Originally Posted by wstar

^ VVEL is always active, it's pretty integral to how the ECU operates this engine (VVEL != VTEC). I'm pretty sure the normal throttle butterflies *do* vary in some situations though, they're not completely static.

VVEL is not like Vtec. VVEL controls valve timing on intake and exhaust. VTec controls the valves in Honda you have a extra lobe on the cam when activated these open all the valves will open using this hotter lobe on the cam. Now i-Vtec adds the VVEL to the mix with variable valve timing to the intake and exhuast for better performance through the RPM band.

wstar · 08-04-2012, 10:22 AM

I think maybe you misread me, I said VVEL != VTEC

. Also VVEL doesn't control the exhaust valves, just the intake ones.

kenny's 370z · 08-04-2012, 01:33 PM

Quote:

Originally Posted by IcedZ

Interesting.. I never looked at that. Did it make any difference?

no ! ive had it with this car and i am ready to get rid of it.worse car i have ever owned since a caliber with a cvt tranny

edit; i had a bad map sensor with no codes.fixed and operating perfectly

08-02-2012, 08:26 PM	#796 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	Well the AT's first gear comes out at a lower ratio than the MT's, even given the worse ratio in the final drive. That's probably most of it. The lockup torque convertor works great, so you don't see as much slippage loss as traditional ATs. And of course 7ATs have the torque multiplication factor going for them too when you first engage. __________________ 7AT Track Car! Journal thread / Car setup details

08-03-2012, 11:20 AM	#799 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	The only sane way to disable VVEL is to replace the heads. VVEL is an oil-pressure-driven mechanical system with an eccentric shaft, etc. The electronic servo just controls the angle between the shafts. Somehow disabling the ECU's control of it would probably be catastrophic. Have you gone over all the basic maintenance/inspection stuff? PCV system, air filters (not clogged, not leaking air around them from a bad seal, etc?), clean the MAF sensors, reset the idle air volume, check for exhaust / intake tract leaks, etc. There are a lot of "little" things that can adversely affect engine performance. __________________ 7AT Track Car! Journal thread / Car setup details Last edited by wstar; 08-03-2012 at 11:22 AM.

08-03-2012, 12:03 PM	#800 (permalink)
kenny's 370z Base Member Join Date: Jun 2012 Location: TN Age: 58 Posts: 243 Drives: 2012 frontier sv v6 Rep Power: 13	the only thing i havnt done yet is to replace the spark plugs. edit;on lunch today,i took the grounds back off the throttle bodies and i believe the grounds were hurting more than helping.this car is like a woman.moody as hell lol Last edited by kenny's 370z; 08-03-2012 at 01:47 PM.

08-03-2012, 06:36 PM	#803 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	^ VVEL is always active, it's pretty integral to how the ECU operates this engine (VVEL != VTEC). I'm pretty sure the normal throttle butterflies do vary in some situations though, they're not completely static. __________________ 7AT Track Car! Journal thread / Car setup details

08-03-2012, 10:20 PM	#804 (permalink)
kenny's 370z Base Member Join Date: Jun 2012 Location: TN Age: 58 Posts: 243 Drives: 2012 frontier sv v6 Rep Power: 13	i took that sensor out that is connected to the vvel motor that goes in the top back side of the im.it was oily.not dripping, but oily.so when you clean the maf sensors,hit that one too. i also found this interesting; http://www.allanglesdesign.com/porta.../CCV_Bible.pdf Last edited by kenny's 370z; 08-03-2012 at 10:52 PM.

08-04-2012, 12:18 AM	#805 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	I really like that PDF, good explanations I haven't seen elsewhere. Currently my car is in his "Stage 1" config. I have a really good quality baffled can on the PCV side, and stock hose on the fresh air side. (Well, our car has two of each of those lines, and I've run my PCV lines together with a Y-adaptor for a single can). It's tempting to go ahead and run dual cans with his stage 3 setup for the NA 370Z, and I might get around to that someday. You could use the existing fresh air paths since we already have two of them, just replace those plastic baffled things with regular hose through cans, and then cap off the PCV valves and corresponding manifold connections. __________________ 7AT Track Car! Journal thread / Car setup details

08-04-2012, 04:03 AM	#807 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	It could be that it lives in the flow of oil and is always oily __________________ 7AT Track Car! Journal thread / Car setup details

08-04-2012, 10:22 AM	#809 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	I think maybe you misread me, I said VVEL != VTEC . Also VVEL doesn't control the exhaust valves, just the intake ones. __________________ 7AT Track Car! Journal thread / Car setup details

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