ultragauge shows my p5 stuck in open loop.

I went for a drive today to see what kind of numbers I'm getting with the UG. When the car was fully warmed up, I hit full throttle in 5th gear starting at 1,200 RPM. Both O2 sensors went to 0.915 V and stayed there for a few seconds. Then the second O2 sensor went up to 0.920 and the first O2 sensor dropped right down after that in what I figure was an attempt to bring the reading of #2 O2 back to 0.915 V. When O2 #2 went back to 0.915, they both stayed steady at 0.915 again.
This suggests to me that even though I was WOT, the ECU is using its MAP (ECU table) to maintain a constant voltage on both O2's and may well be in closed loop all the time. Perhaps the UG is waiting for a switching point in and out of closed loop and we don't have one,... It's always closed. ???
The UG is reading our cars with the 9141 protocol which they say is very inefficient and out dated My refresh rate is 0.9 seconds (after using the "optimizer") so perhaps that is what the cached data is about. As long as I can hold my throttle down for more than 0.9 seconds I feel I can get an accurate reading, just with bad resolution.


From UG manual:
Fuel Trim Gauge:

Fuel trim refers to the fine tune control of fuel delivery and specifically indicates adjustments made dynamically to the base fuel
table to obtain the proper ratio of fuel to air. The fuel-to-air ratio is adjusted by increasing or decreasing the time fuel injectors
are open. Note that fuel injectors are either fully open or fully closed - there is no variable opening.
Fuel trim is generally calculated by using a wide set of data values, including forward O2 sensors, intake air
temperature/pressure or air mass sensor, barometric pressure, humidity, engine coolant temp, anti-knock sensors, engine load,
throttle position , and battery voltage.
Short term fuel trim refers to adjustments being made in response to temporary short term conditions.
Long term fuel trim is used to compensate for issues that seem to be present over a much longer period or that are essentially
permanent. Long term fuel trim generally should not exceed +- 10% in most vehicles.

Fuel trims are expressed in percentages with a range of -100% to 99.2% of nominal. Positive values indicate a lean condition
exists and the injector is left open longer to compensate, thus adding more fuel. Negative values indicate a rich condition exists
and the injectors are closed more quickly thus reducing the amount of fuel.
Example: A value of 5.0% indicates that the injector is being left open 5% longer than normal, thus the fuel to air ratio is being
increased.
Fuel trim could more appropriately be called “Injection on-time %”.
Fuel trim banks refer to the cylinder banks in a V style engine. Cylinder #1 is always in bank 1. Even though the engine may
contain two physical banks, only a single bank may be reported by the ECM. UltraGauge displays Fuel Trim Banks One and
Two if reported by the vehicle’s engine computer. For those vehicles with three or four banks, only banks one and two will be
available for display on UltraGauge.

UltraGauge supports the following Fuel Trim Gauges:
Short Term Fuel Trim percentage Bank 1
Short Term Fuel Trim percentage Bank 2
Long Term Fuel Trim percentage Bank 1
Long Term Fuel Trim percentage Bank 2

NOTE: If the engine is operating in Open Loop, the short trim will be reported as 0%.

The only time I've noticed the fuel trim being at zero was when I was coasting in gear above idle speed. I'm thinking if you've been driving for a long time with some sort of problem, the fuel trim would adjust for it then show the new settings as normal unless LTF trim shows the value compared to the base fuel table or MAP.


Mass Air Flow 2 Gauge name Range Units Abbreviation
Mass Air Flow 2 g/s 0-999.9 grams/second MA2 g/s

Mass Air Flow (MAF) is the Mass of air entering into the engine. On vehicles with actual
MAF Sensors, there will be two gauges, this gauge and Mass Air Flow 1. Mass Air Flow 1 is
the raw output from the MAF sensor, whereas Mass Air Flow Sensor 2 is the calibrated
version used by UltraGauge to calculate MPG.
The Mass Air Flow is calculated for vehicles that do not have a MAF sensor but rather use a
MAP (manifold absolute pressure) sensor. In this case, MAF is calculated by monitoring
several engine sensors, such as MAP, RPM, Vehicle Speed and others.

I'm thinking if my car had issues, these two readings would be quite different from each other as the ECU adjusts to the engine issues.
 
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Does this issue end up affecting the usability of a Scan Gauge for MPG calculations? I was looking to purchase one to help kind of coach me for getting better gas mileage, but it seems that it may not be a sure bet anymore.

Sorry I can't be of help figuring out this problem, way out of my league!
 
Does this issue end up affecting the usability of a Scan Gauge for MPG calculations? I was looking to purchase one to help kind of coach me for getting better gas mileage, but it seems that it may not be a sure bet anymore.

I've got the Ultra-Gauge so I'm not sure about the scan gauge (I don't know if it shows closed loop or not). This device is still very helpful to me,... it shows the instantaneous gas mileage,.. when the gas is hammered hard, the mileage drops to as low as 5 or 6 MPG when you release the gas it goes up to 156 MPG so you know when you're wasting gas. It comes with a bunch of preset gauges so you just plug it in and enjoy the light show. You can adjust the brightness yourself but it will automatically adjust to ambient light. It has a multitude of gauges to pick from and you can set it to show 4, 6 or 8 gauges per page and it will scan through the pages at your preset timing intervals.
The biggest drawback is the refresh rate, but that is mostly due to our cars dated ECU. (ISO 9141) And you have to answer some skill testing questions to get your $9 rebate. All the questions are just to make sure you don't kill it before you even plug it in.
I haven't read all the directions yet and I need to calibrate it by inputting the amount of fuel I put in at fill-up so it can calibrate itself.
So back to your first question,... I think it is not exact but still very useful (I think it looks better then the scan gauge) but perhaps instead of reading 156 MPG it should read 999.9 MPG while coasting in gear with clutch released. The manual covers this as well and once I wrap my head around these number with the help of some people from this site, I'll send off an e-mail to UG and ask for assistance.
Meanwhile,.. I'll enjoy the blinking lights. It's the best $108 I've spent in quite a while. You guys in the states only pay $8 for shipping and I got the wind shield mount as well. So with the rebate you guys only pay around $68 all in,.. And remember it's also a code reader and resets them as well on any car you plug it in to.
I had my first alarm go off yesterday while I hammered it. My factory set 4,200 RPM rev limit set off the alarm,... That was fun!
 
Woops, I have been looking at so many different makes and models of these types of devices my brain thought they were different levels of the same model. My mistake. However it seems that if you are having good luck with the ultra-gauge, I'm sure the scan-gauge would be just as good since they are very similar. I wasn't sure if the whole closed/open loop thing was completely throwing off the calculations.

I have the Torque app for my android phone and the bluetooth OBII adapter. I was looking for a stand alone unit I could mount in my dash. I will sync my phone up tomorrow and see if Torque reads the car as constantly being in open loop.
 
It seems that if you are having good luck with the ultra-gauge, I'm sure the scan-gauge would be just as good since they are very similar. I wasn't sure if the whole closed/open loop thing was completely throwing off the calculations.

I have the Torque app for my android phone and the bluetooth OBII adapter. I was looking for a stand alone unit I could mount in my dash. I will sync my phone up tomorrow and see if Torque reads the car as constantly being in open loop.

I was going to mention the Bluetooth adapter for those who might be looking for another option. I understand it's only about $20. It is now illegal to use a cell phone while driving here in Ontario unless it's hands free,... there was a woman who turned her's to speaker phone and had it in her lap and still got a ticket. That would be very similar to the Android app. I personally prefer the look of the UG over the SG. The screen display on the SG looks kinda chunky but it does have a better matching orange background for our cars. The UG is a little smaller than it appears on the website,(2 1/2" by 3 1/2") but I prefer that, it's still very easy to read.

I still don't know if it's just the UG or all of them that don't register closed loop. I'm looking forward to hearing what your gauge tells you.

I think this gauge is worth the money for the Volt Meter and Coolant Temp. gauges alone. (My alternator crapped out about a year ago and started putting out 17 Volts,... the idiot light did come on but it was during the day and I could barely see the light (my sister had to point it out to me) now I have an alarm with lots of cool blinking lights to alert me).
 
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Eulogy83 said:
pcb said:
Did you find out anything more on the UG always showing closed loop??

I had sent an email to the company and they had no information to give me. So I just chalked it up to it will always read it as open. After a while researching this I have noticed other makes and models have this problem as well.

OK Installshield 2: It up to you now.

I'm sure that we can make some sort of sense of the data we are getting.
 
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Did a little driving with the Torque app today. Sadly I forgot to plug everything in after the car had been sitting overnight. So I haven't tested it on a true cold start. During one start the temperature gauge started at it's lowest point, but the car had only been sitting for about an hour and a half. However, during all of this it always said it was in closed loop. With the only exception being that when you decelerate with no throttle it switches to open loop. I took some screen shots on my phone to show what it is saying.

<iframe src="https://skydrive.live.com/embed?cid=5AA886B2BC80B78C&resid=5AA886B2BC80B78C%21236&authkey=AGED7s_f7GEaxV8" width="180" height="320" frameborder="0" scrolling="no"></iframe> <iframe src="https://skydrive.live.com/embed?cid=5AA886B2BC80B78C&resid=5AA886B2BC80B78C%21237&authkey=ANer3qzjQfQi9JA" width="180" height="320" frameborder="0" scrolling="no"></iframe>
 
Thanks Luken10

That really helps a lot. (unless you did some photo shop magic to twist up this thread,.. haha) Anyway, I think I have enough information now to send off an informed e-mail to Ultra-Gauge. Apparently our car is the ONLY car out there (other than diesels) that doesn't read closed loop (with the help of Eulogy83's e-mail. They were trying to say our cars were at fault ie. not working properly).
I definitely think the UG might need a flash upgrade for our cars,... and great news,... they give free upgrades (but you have to pay shipping Both ways that's $54.12 for me,.. that sucks,... I'd be better off buying a new one if they fix this problem).
Anyway I'm on it.
 
pcb

if you want a pic of my scangauge saying closed loop to go with Luken10's pic I can go take one for you
 
Cool that would certainly help,... I can't figure out how to copy and paste and all that interweb stuff, but I'm going to send a link to this thread along with my e-mail (I think I can manage that)
Hopefully they might meet me half way with a new gauge or at least tell us how to make sense of the numbers we do get (like the fuel cut system,... I'm almost sure the injectors shut off while coasting in gear because the O2 readings drop to zero but the fuel trim reads 0, so the UG is still recording fuel use, they talk about that specific thing in the manual (58 pages,.. quite the read) and say it doesn't add up to too much (after all it would only be the amount of gas used to idle the car being misread during coasting), but it would throw off the readings)
I'll wait for your pictures either way and read more of the manual. (I haven't even set up my calibrations yet). It takes a while to feel informed about this gauge.
They were very helpful with my first e-mail on how to take the gauge with me every time I leave the car.
 
image-12.jpg
 
OK that helps.

I'll try to send a link to this thread when I write my e-mail to UG,... I better read the manual again and try to calibrate it as best as I can first.
 
Here's what Ultra-Gauge said open and closed loop

Vehicle Make: Mazda
Vehicle Model: Protege 5
Vehicle Year: 2002
Engine Size: 2.0
Tranmission: Manual
Protocol found: 9141
UltraGauge Type: EM 1.2
Message:

My Ultra-gauge is reading that my car is always in open loop. My car is a 2002 Mazda Protege 5. I've been asking on the Mazda 247 car forum if their car ever reads closed loop and nobody with this car and an Ultra-Gauge has ever seen it in closed loop. Both scan gauge and even the blue-tooth android app combination show our car in closed loop. The people on the forum actually sent pictures of their car in closed loop mode with the scan gauge and blue tooth app.
Our cars use two O2 sensors in series and I do get a reading of 0 Volts on both sensors when decelerating in gear but the Instantaneous MPG went to 139 not the 999.9 that I would expect. My car is running very well and has no codes. It passed emissions testing with almost unmeasurable pollutants.
If your gauge simply won't read our car in closed loop I was hoping to get some advice as to how to set up, read and understand the numbers we are getting.


Date: 02-11-2013 08:33:55
Name: UltraGauge

Message:

UltraGauge is reading the loop status directly from the Mazda's ECM. The ECM is reporting open or closed loop, UG is just relaying the information.

The other tools are likely using some other method to determine open/closed loop status which may or may not be accurate.
Without loop status the Fuel Injection Cut off feature in UG will not function and you will not see 999.99 MPG. However, the reality is that that this feature and Cut-off in general has very little effect upon the Average MPG.

Best regards,

UltraGauge Support
www.ultra-gauge.com
Support is available Monday, Wednesday and Friday, 9-5pm Central Time
 
^^looks like they gave you the run around, bud...

Open and closed loop isn't a case by case standard for all ecu's...its merely a layman description for a specific way of determining an AFR and ignition timing...every car runs a 'closed' loop protocol a little differently, and may use different sensors also...

The UG rep is basically saying their device waits for the car's computer to blatantly say 'hey, i'm in closed loop now'...and it doesn't work like that...the UG has to be able to correlate what sensors the ecm is actually reading and adjusting in order to be 'aware' of what type of operation protocol its currently in...some ecu's may output a simple 'status' that tells the diagnostic port whats going on...and i'm not sure if ours do that or not, but whatever it does...it doesn't seem to be in a programming language that the UG fully understands...

its seems some devices are able to properly do that with the EEC-V ecu...but possibly the UG is not one of them...the most troubling thing, imo, is that the rep acts as if the other devices are 'inaccurate'...kind of ridiculous considering your car passes emissions properly...as if it was stuck in open loop, as the UG seems to be saying...that wouldn't be the case at all...
 
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Oh Well,...

I still think it's a great instrument (voltmeter and coolant temp alone). I'm gonna go for a drive and hammer it in 2nd or third gear while watching the O2 reading. I'm expecting to see a change as soon as I hit the 3100-3300 range when the car goes rich.
 
I noticed the O2 reading went higher (richer) after the 3100 RPM or so range. It was kinda hard to observe because of my 0.9 second refresh rate and the fact that it gains speed quickly in third gear. I was near red-line before it registered the 3100 reading. I did notice that in fifth gear starting at 1500 rpm then WOT the car seemed to try to hold the O2 reading at 0.915. The acceleration was slower and easier to follow with the meter. I didn't take it up to the 3100 RPM mark because I was on a mushy gravel road.
 
does your UG have a reading for both o2 sensors? as in, is it separated? Do you know which sensor is giving those voltage numbers, or are they always the same?
 
Yes, there is a reading for both O2 sensors. When the car is first started, even when cold out, both sensors read 0.455 V. The first O2 starts to fluctuate just seconds after start-up (perhaps that is what the other gauge is using as is closed loop trigger) but the second O2 sensor needs a good couple of minutes to start fluctuating from 0.455 V. You can actually see the car warming up with the O2 sensor readings, coasting in gear. With the car cold, the O2 reading while coasting stays at about .3-.4 volts and slowly drops to 0 V when the car is fully warmed up. It seems that the reading off the second O2 sensor is the one that needs to be maintained. When second O2 sensor reading goes up or down the first O2 reading fluctuates wildly in what appears to be an attempt to bring the value back to it's predetermined setting. All this seems to start just seconds after starting the car.
 
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