Gas Pedal Delay

Westwood · 09-11-2010, 09:36 PM

Quote:

Originally Posted by 6spd

i personally would rather have a tune than lose the ability to better modulate the throttle, which i would expect from a chip that goes WOT in a shorter pedal press.

agree but how much will it be for a tune 600$+

6spd · 09-11-2010, 10:00 PM

Quote:

Originally Posted by Westwood

agree but how much will it be for a tune 600$+

yep. it would seem that for getting rid of the slight delay and it being worthwhile, you'd either have to have money to burn or a damn good reason, like the z being your competitive track car. neither are probably in the realm of possibility for a lot of us, rendering the need for this gadget or a tune (strictly for this reason) relatively unneeded.

Zeto · 09-12-2010, 12:00 AM

Once again guys, I have an Uprev tune and still have this issue.

christian370z · 09-12-2010, 12:34 AM

Quote:

Originally Posted by Zeto

Once again guys, I have an Uprev tune and still have this issue.

Yes, but that could just be that your tuner did not play with the throttle mapping. From what I have been told by popular tuners like SpecialtyZ and Technosquare (along with members who have been tuned) is that effective tuning of the throttle maps can make a big difference.

This coming wednesday, I am getting my Z tuned so I will be letting you know!

cossie1600 · 09-12-2010, 05:44 AM

Also note how the problem seems to be more noticeable on automatic cars? I bet Nissan just dumbs down the throttle response even more to protect the AT. If I recall correctly, the automatic I drove did the same exact thing

DIGItonium · 09-12-2010, 11:44 AM

The automatic Z I test drove over a year ago did not have this issue, and the temps were cooler at the time it was being tested. It was the first time testing a 370Z, and my initial impression was that it was eager to rev to past 3k with little throttle tip in. I was sold and ordered the 6MT.

What I would like to see done since I don't have the funds to get the appropriate tools, is to get a data acquisition board of some sort to record the voltages for the gas pedal, ECU outputs, VVEL outputs, stepper motor inputs, and temperatures in different areas including the stepper motor assembly. All of this data would be logged and graphed to observe temperature and the relationship of the signals controlling throttle response.

The gas pedal voltage should be 100% linear from 0-5V.
The ECU throttle output may not have a 1:1 correlation to the gas pedal potentiometer.
The VVEL controller, which I know nothing about, I will assume is a black box with input and output to control the stepper motor.

Somewhere along the lines of capturing this data and graphing it we should see somewhere in the system of gas pedal travel (2nd gear, pressing pedal from position 0 to max) we should be able to graph the delays and compare it to temperature. Obviously something's getting hot and slow. Has anyone felt the stepper motors? That thing is scorching hot. I'd be curious to know where the VVEL "box" is located as well.

[EDIT] Service manual indicates there are terminals for the VVEL Control Shaft Position sensor, so the voltage levels can be measured here. Then there's the VVEL Actuator motor which we can probably log and compare with the sensor values. Just for kicks, we can log the TPS sensor as well.

IcedZ · 09-12-2010, 03:35 PM

Quote:

Originally Posted by DIGItonium

The automatic Z I test drove over a year ago did not have this issue, and the temps were cooler at the time it was being tested. It was the first time testing a 370Z, and my initial impression was that it was eager to rev to past 3k with little throttle tip in. I was sold and ordered the 6MT.

What I would like to see done since I don't have the funds to get the appropriate tools, is to get a data acquisition board of some sort to record the voltages for the gas pedal, ECU outputs, VVEL outputs, stepper motor inputs, and temperatures in different areas including the stepper motor assembly. All of this data would be logged and graphed to observe temperature and the relationship of the signals controlling throttle response.

The gas pedal voltage should be 100% linear from 0-5V.
The ECU throttle output may not have a 1:1 correlation to the gas pedal potentiometer.
The VVEL controller, which I know nothing about, I will assume is a black box with input and output to control the stepper motor.

Somewhere along the lines of capturing this data and graphing it we should see somewhere in the system of gas pedal travel (2nd gear, pressing pedal from position 0 to max) we should be able to graph the delays and compare it to temperature. Obviously something's getting hot and slow. Has anyone felt the stepper motors? That thing is scorching hot. I'd be curious to know where the VVEL "box" is located as well.

[EDIT] Service manual indicates there are terminals for the VVEL Control Shaft Position sensor, so the voltage levels can be measured here. Then there's the VVEL Actuator motor which we can probably log and compare with the sensor values. Just for kicks, we can log the TPS sensor as well.

THIS is EXACTLY what I've been trying to get!

6spd · 09-12-2010, 03:56 PM

that kind of scan gear is gonna run someone quite a tab, if it is even possible to get. like i said, it is gonna take a cooperative dealer, and that is more scarce than... well something that doesn't exist!

wilsonp · 09-12-2010, 04:01 PM

Actually, hardware like USB DMMs to record voltage over time isn't expensive, though the data logging software can be. I believe you can even do logging with some TI calculators with the right kit. The problem might be syncing with an OBD II logger.

My 2009 Auto hasn't exhibited the problem at all, so I can't do any testing.

IcedZ · 09-12-2010, 11:13 PM

Quote:

Originally Posted by wilsonp

Actually, hardware like USB DMMs to record voltage over time isn't expensive, though the data logging software can be. I believe you can even do logging with some TI calculators with the right kit. The problem might be syncing with an OBD II logger.

My 2009 Auto hasn't exhibited the problem at all, so I can't do any testing.

Exactly. The actual hardware isn't that expensive. However, the software can be. And it's very niche software. Interfacing with OBD is the hard part (for me anyway).

flashburn · 09-12-2010, 04:14 PM

Last time I was doing data logging with Uprev I noticed there were like 4-5 different VVEL things that you can log/monitor. If this would be useful to anyone, I can find out what things it can log. I can't do any useful logging though since I can't reproduce this problem either.

DIGItonium · 09-12-2010, 11:29 PM

Datalogging software isn't needed as long as the voltages can be recorded over time and stored in a comma delimited text file. I use open source library, ZedGraph, to graph data with several hundred thousands of points. If you guys like, I can write a simple program that uses this library to import individual csv files and plot them as separate graphs or overlays.

Datalogging with UpRev is one thing, but we need to acquire signals at the source (I/O control signals and driver output). The ECU and VVEL module output signals to control the throttle and VVEL actuators and each has its own position sensor, but I don't know the system well enough to determine if the control signal output to the actuator goes from A to B in X milliseconds that the actuator is expected to physically change positions from A to B in X milliseconds as well.

In other words, we might have a situation where the control signal expects the actuator to move from point A to B. The actuator does move from point A to B, but there is no mention about how fast it should get there to meet the timing tolerance. It is like playing an FPS game with a wireless keyboard and mouse getting pwned from the 0.5s lag.

IcedZ · 09-13-2010, 12:18 AM

Quote:

Originally Posted by DIGItonium

Datalogging software isn't needed as long as the voltages can be recorded over time and stored in a comma delimited text file. I use open source library, ZedGraph, to graph data with several hundred thousands of points. If you guys like, I can write a simple program that uses this library to import individual csv files and plot them as separate graphs or overlays.

Datalogging with UpRev is one thing, but we need to acquire signals at the source (I/O control signals and driver output). The ECU and VVEL module output signals to control the throttle and VVEL actuators and each has its own position sensor, but I don't know the system well enough to determine if the control signal output to the actuator goes from A to B in X milliseconds that the actuator is expected to physically change positions from A to B in X milliseconds as well.

In other words, we might have a situation where the control signal expects the actuator to move from point A to B. The actuator does move from point A to B, but there is no mention about how fast it should get there to meet the timing tolerance. It is like playing an FPS game with a wireless keyboard and mouse getting pwned from the 0.5s lag.

Good point.
Does anyone have a scrap OBD-II cable they would be willing to mail me? I literally just need the cable to plug into the car. I will be breaking it out into a breadboard, so I preferably do not want it coming from something working. I have an NI 14 bit DAQ that will be perfect for this.

DIGItonium · 09-13-2010, 07:13 AM

Quote:

Originally Posted by IcedZ

Good point.
Does anyone have a scrap OBD-II cable they would be willing to mail me? I literally just need the cable to plug into the car. I will be breaking it out into a breadboard, so I preferably do not want it coming from something working. I have an NI 14 bit DAQ that will be perfect for this.

Oh snaps... how many channels? I guess we can start with one side (i.e., left/right actuators and sensors) with common inputs (gas pedal potentiometer, temps, etc.). Definitely create the "cool" logs where the car behaves normally, and "hot" logs where the car starts lagging. I'll try to find some time this week to write a small program using ZedGraph.

IcedZ · 09-13-2010, 10:53 AM

Quote:

Originally Posted by DIGItonium

Oh snaps... how many channels? I guess we can start with one side (i.e., left/right actuators and sensors) with common inputs (gas pedal potentiometer, temps, etc.). Definitely create the "cool" logs where the car behaves normally, and "hot" logs where the car starts lagging. I'll try to find some time this week to write a small program using ZedGraph.

8 analog channels, 12 digital I/O channels.

09-12-2010, 11:44 AM	#6 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 44	The automatic Z I test drove over a year ago did not have this issue, and the temps were cooler at the time it was being tested. It was the first time testing a 370Z, and my initial impression was that it was eager to rev to past 3k with little throttle tip in. I was sold and ordered the 6MT. What I would like to see done since I don't have the funds to get the appropriate tools, is to get a data acquisition board of some sort to record the voltages for the gas pedal, ECU outputs, VVEL outputs, stepper motor inputs, and temperatures in different areas including the stepper motor assembly. All of this data would be logged and graphed to observe temperature and the relationship of the signals controlling throttle response. The gas pedal voltage should be 100% linear from 0-5V. The ECU throttle output may not have a 1:1 correlation to the gas pedal potentiometer. The VVEL controller, which I know nothing about, I will assume is a black box with input and output to control the stepper motor. Somewhere along the lines of capturing this data and graphing it we should see somewhere in the system of gas pedal travel (2nd gear, pressing pedal from position 0 to max) we should be able to graph the delays and compare it to temperature. Obviously something's getting hot and slow. Has anyone felt the stepper motors? That thing is scorching hot. I'd be curious to know where the VVEL "box" is located as well. [EDIT] Service manual indicates there are terminals for the VVEL Control Shaft Position sensor, so the voltage levels can be measured here. Then there's the VVEL Actuator motor which we can probably log and compare with the sensor values. Just for kicks, we can log the TPS sensor as well. __________________ Last edited by DIGItonium; 09-12-2010 at 12:08 PM.

09-12-2010, 03:56 PM	#8 (permalink)
6spd A True Z Fanatic Join Date: Aug 2009 Location: South Florida Posts: 3,001 Drives: Q50RS Rep Power: 26	that kind of scan gear is gonna run someone quite a tab, if it is even possible to get. like i said, it is gonna take a cooperative dealer, and that is more scarce than... well something that doesn't exist! __________________ -Jay- jonathanjamesphotographer.com

09-12-2010, 04:01 PM	#9 (permalink)
wilsonp A True Z Fanatic Join Date: Jul 2010 Location: Virginia Posts: 1,134 Drives: 2009 Touring Sp Nav Rep Power: 18	Actually, hardware like USB DMMs to record voltage over time isn't expensive, though the data logging software can be. I believe you can even do logging with some TI calculators with the right kit. The problem might be syncing with an OBD II logger. My 2009 Auto hasn't exhibited the problem at all, so I can't do any testing. __________________ 2014 Cayman S PDK Sport Chrono White/Black Was 2009 370Z Touring Sport+Nav 7AT Metallic Black/Persimmon Was 1991 NSX Auto Black/Black

09-12-2010, 04:14 PM	#11 (permalink)
flashburn A True Z Fanatic Join Date: May 2009 Location: Central Florida Posts: 1,884 Drives: '12 Corvette GS 6M Rep Power: 20	Last time I was doing data logging with Uprev I noticed there were like 4-5 different VVEL things that you can log/monitor. If this would be useful to anyone, I can find out what things it can log. I can't do any useful logging though since I can't reproduce this problem either. __________________ Current Ride: 2012 Chevrolet Corvette Grand Sport Centennial Edition Carbon Flash 6M Previous Ride: 2009 Nissan 370Z Sport Platinum Graphite 7AT

09-12-2010, 11:29 PM	#12 (permalink)
DIGItonium A True Z Fanatic Join Date: Jan 2009 Location: Kansas Posts: 3,800 Drives: 09 Z34-TT 6MT Rep Power: 44	Datalogging software isn't needed as long as the voltages can be recorded over time and stored in a comma delimited text file. I use open source library, ZedGraph, to graph data with several hundred thousands of points. If you guys like, I can write a simple program that uses this library to import individual csv files and plot them as separate graphs or overlays. Datalogging with UpRev is one thing, but we need to acquire signals at the source (I/O control signals and driver output). The ECU and VVEL module output signals to control the throttle and VVEL actuators and each has its own position sensor, but I don't know the system well enough to determine if the control signal output to the actuator goes from A to B in X milliseconds that the actuator is expected to physically change positions from A to B in X milliseconds as well. In other words, we might have a situation where the control signal expects the actuator to move from point A to B. The actuator does move from point A to B, but there is no mention about how fast it should get there to meet the timing tolerance. It is like playing an FPS game with a wireless keyboard and mouse getting pwned from the 0.5s lag. __________________

09-12-2010, 12:00 AM	#3 (permalink)
Zeto Track Member Join Date: Apr 2009 Location: North NJ Age: 42 Posts: 766 Drives: 09 Pearl White 370Z Rep Power: 269	Once again guys, I have an Uprev tune and still have this issue.

09-12-2010, 05:44 AM	#5 (permalink)
cossie1600 A True Z Fanatic Join Date: Jun 2009 Location: californee way Posts: 5,380 Drives: 370, Leaf Rep Power: 31	Also note how the problem seems to be more noticeable on automatic cars? I bet Nissan just dumbs down the throttle response even more to protect the AT. If I recall correctly, the automatic I drove did the same exact thing

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
7AT rev delay?	Vegitto-kun	Engine & Drivetrain	16	05-04-2010 05:17 PM
2 things delay in a shift and a sound 7at	jtown82	Engine & Drivetrain	19	04-03-2010 01:30 AM
Headlight delay	Jack370Z	Nissan 370Z General Discussions	7	10-30-2009 03:02 PM
A7 Upshift Delay?	hey32g	Nissan 370Z General Discussions	15	10-12-2009 11:20 AM
Automatic Downshift Delay	drdre8424	Nissan 370Z General Discussions	2	07-25-2009 10:56 PM