Stock ECU Native Wideband Review

[->PrOjEcTGS<-]

For those of you that delve into the depths of burning your own EPROM chips for the stock ECU you might find this interesting. I recently used the code found on the DSM-ECU Yahoo Group to wire my AEM UEGO directly to the ECU for a native wideband.

Yahoo! Groups

I was hoping that this would keep my car precisely at or around 14.7 during closed loop. While the code does work and work very well what I did notice was that my AFR during closed loop seemed to fluctuate more that it used to with the stock narrowband. It would cycle anywhere between 13.5 to 15.9. This was unacceptable in my book seeing as how the sole purpose of the closed loop operation is to maintain the preprogrammed AFR to cycle around. 14.7:1. On the highway you could feel a surging sensation as the car would lean out and richen up. Therefore I believe that having a native wideband for our purposes on the stock ECU is overrated and unneeded. Unless of course you are running a stand-alone EMS system that was designed around it. I switched back to the stock NB sensor which seems to do it's job fairly well. I do still have the WBO2 hooked up to the EGR-T input for logging purposes though.

Any thoughts on this are welcome.



Here's the code if anyone is interested:
// old
< d69e: 96 ce ldaa *0xce // O2 sensor
< d6a0: 81 1f cmpa #31 // if O2 < 31 (.5v) (lean)
< d6a2: 24 03 bcc 0xd6a7 // (branch carry clear)

// new
> d69e: 96 ce ldaa *0xce // WBO2 sensor
> d6a0: 81 7a cmpa #122 // if WBO2 >= 122 (2.4v) (lean)
> d6a2: 25 03 bcs 0xd6a7 // (branch carry set)

d6bf: d6 ce ldab *0xce // WBO2 sensor
d6c1: c1 7a cmpb #122 // if WBO2 >= 122 (2.4v) (lean)
d6c3: 25 03 bcs 0xd6c8 // (branch carry set)

d7fc: 96 ce ldaa *0xce // a = WBO2 sensor
d7fe: 81 80 cmpa #128 // WBO2v >= 128 (2.5v) (lean)
d800: 32 pula // a = O2trim
d801: 25 07 bcs 0xd80a // if WBO2v >= 2.5v

e61c: 96 ce ldaa *0xce
e61e: 81 7a cmpa #122 // WBO2 < 2.4v (rich)
e620: 24 02 bcc 0xe624

f08b: d6 ce ldab *0xce // WBO2 sensor
f08d: c1 80 cmpb #128 // WBO2v >= 128 (2.5v) (lean)
f08f: 25 0d bcs 0xf09e

 

[toofast82]

yeah ive heard that it cycles more often when using native wideband. That crazy that you can actually feel the surging on the highway. I was going to do this in the spring but i guess not!, thanx for the input. How well was it adjusting at wot with your a/f settings in the chip?

 

[->PrOjEcTGS<-]

yeah ive heard that it cycles more often when using native wideband. That crazy that you can actually feel the surging on the highway. I was going to do this in the spring but i guess not!, thanx for the input. How well was it adjusting at wot with your a/f settings in the chip?

Yea I thought it was a going to be a good idea also, but it ended up just hurting driveability.

When you're at WOT you are in open loop where the ECU doesn't look for feedback from the O2 sensor. That's why I think the NB does a better job for our application since it's only used during closed loop operation. Best thing about it was that it was voltage was loggable.

 

[bling5tatus]

I've been running native wideband on my car that I put 30k miles on in the year of 2008... I have no fluctuation issues... but I am also using full load based tuning.... so I fixed my AFR's where I wanted them. I would not recommend this to people that don't have a robust tuning system (read: no safc's)

 

[->PrOjEcTGS<-]

I can understand using DS-Map how you would want to use the WBO2 sensor natively. Since most of the time you have the ECU locked in Open Loop and will not use Closed Loop operation. You don't have fluctuation since you don't use closed loop.

 

[bling5tatus]

I have run my car in closed loop w/o fluctuation as well. I decided that closed loop was for the birds though. I don't like the ecu trying to "control" things.

Is there any definitive proof as to why you would have been getting fluctuation?

 

[toofast82]

Bling5tatus: Are you using DsMap V2 currently?
Im using the speed density files on the yahoo forums which are based on E931. Just curious how the V2 was working out for you if youre running it because they completely redid the code.

 

[bling5tatus]

I certainly am, it works great. I have no reason to support the site/product other than the fact that I took it upon myself to use and it turned out to be an EXCELLENT choice. I would recommend this conversion to anyone using a 1g eprom ecu. We even have some forum members that have used dsmlink in the past and claim that dsmap has superior throttle response and part throttle power comparatively.

 

[jrohner]

Most likely the reason the AFR swings back and forth a lot is because of how far back you have it mounted. The farther back it is, the slower the response time is going to be. On my 2g, I have mine way back in about the stock 2nd o2 sensor location and my AFR swings back and forth; mostly when it's not warmed up or at an idle (warmed up cruising it swings .5:1 max in each direction). I've heard of evo guys on the evolutionm forums actually mounting the wideband in the stock position up on the o2 housing with good results; I wouldn't risk my sensor like that -- I want to put mine near the flex section on the downpipe.

 

[->PrOjEcTGS<-]

It's mounted about 3 inches behind the flex section. I'm just going to hold out on using the WB input till I switch over to DS-Map.

Sorry, guys I'm sure it works great for you but I'm just reporting my findings.

 

[steve]

One point made was, if your seeing too much of a swing you might want to tighten up the switching points and make sure that they are accurate for the AFR your trying to hit. With a WB sensor providing feedback you could just as easily set it up to run any AFR you desire in closed loop.

Once you have that down you can look at the code so more and see if the factory maps for the closed loop dithering make sense in your setup.

 

[->PrOjEcTGS<-]

I guess that's what I'll try to do tighten up the switching points. Is the general consensus that the closer the switching points the better?

On AEM's paper, lamda is roughly @ 2.34v (14.68AFR) so should I have it switch around that voltage with 119 = 2.32v or 14.64 AFR (rich) and 121 = 2.35 or 14.70 AFR (lean)

Besides my positioning of the sensor do any of you think that would help?

 

[jrohner]

I did see a test on a bunch of widebands and the lc1 was most accurate and had the fastest response. No this test was not conducted by Innovate (as far as I know).

I configure my wideband to simulate a narrowband and I run my 2 switch points about 1 AFR apart from each other.

 

[->PrOjEcTGS<-]

Not trying to beat on you at all mang .

The flex could be offering some air into your exhaust. Secondly, stock location has worked on numerous cars for close to 3 years now (close friends).

Run your code, with it back at the stock location and reply your sweeps if they occur.

Lastly, the aem white papers, are totally wrong... they try to say its v * 2 + 10. However it is more like + 9.3 and even then, some areas it is lean / rich by 0.1. I've had hell writing my software to match peoples gauge outputs, and the fact of the matter is, either their paper is right, and the gauges they use with the sensors are wrong, or the gauge is right and the paper is wrong.

I'd like to think their gauges are right , but still lots of issues w/ non-programmable wideband units. If you are going to be running dsmap, I would suggest you swapping your aem to a lc1 or jaw. It will save you a lot of head ache in the long run.

Even the zeintronix whitepapers don't match the outputs.

Well, I took your advice because I really WANT this to work. I sold the AEM UEGO and bought an LC-1. It should be here in a couple days. You're right the UEGO is very lacking in it's abilities.

 

[We're on Boost]

You guys with LC-1's, where are you mounting it?
I've been thinking about buying one with G4 gage. I talked to Innovate tech support last week, they told me the wire from the sensor to the LC-1 is only 20" long. They also told me the LC-1 should be mounted nowhere near the turbo or anything else hot, should be mounted low so as to be in cooler air. Well my bung is in the downpipe about a foot below the O2 housing flange. They said the wire is short to minimize electro-magnetic interference. Anyway, I looked around for a spot that I could reach with a 20" wire run and wasn't very happy about it. So I'm wondering where you guys are putting them.

Otherwise the Innovate looks mighty interesting. The AEM, lot of people use it, but the gage only goes down to 11 - ? Innovate tech says they use the same Bosch sensor AEM does but their controller is completely different. They say the LC-1 is accurate down to about 7.35 a/f. The G4 gage reads to 8 and it is an analog-appearing stepper motor gage. Just what I want.

Gary

 

[->PrOjEcTGS<-]

You guys with LC-1's, where are you mounting it?
I've been thinking about buying one with G4 gage. I talked to Innovate tech support last week, they told me the wire from the sensor to the LC-1 is only 20" long. They also told me the LC-1 should be mounted nowhere near the turbo or anything else hot, should be mounted low so as to be in cooler air. Well my bung is in the downpipe about a foot below the O2 housing flange. They said the wire is short to minimize electro-magnetic interference. Anyway, I looked around for a spot that I could reach with a 20" wire run and wasn't very happy about it. So I'm wondering where you guys are putting them.

Otherwise the Innovate looks mighty interesting. The AEM, lot of people use it, but the gage only goes down to 11 - ? Innovate tech says they use the same Bosch sensor AEM does but their controller is completely different. They say the LC-1 is accurate down to about 7.35 a/f. The G4 gage reads to 8 and it is an analog-appearing stepper motor gage. Just what I want.

Gary

The AEM UEGO's gauge reads down to 10.0 That sucks when trying to tune out a rich condition since you can't tell how far you need to go. Then when the analog output doesn't match the gauge's output it's really hard to tell which one to trust.

I'll probably mount mine on the firewall ziptied to a hard brake line or something like that. My sensor is mounted in the exhaust like this:

Then I'll run the rest of the cable through an existing hole in the firewall.

 

[We're on Boost]

I'll probably mount mine on the firewall ziptied to a hard brake line or something like that. My sensor is mounted in the exhaust like this:

Then I'll run the rest of the cable through an existing hole in the firewall.

Thanks for the good pic!
Let's see, if that is your power transistor in the foreground, then the O2 sensor is aft of the engine just a few inches forward of the firewall. So you could put your LC1 on the firewall no problem. Darn, my bung location might not work out because it is so far forward.

Gary

 

[MY1GDSM]

The AEM UEGO's gauge reads down to 10.0 That sucks when trying to tune out a rich condition since you can't tell how far you need to go. Then when the analog output doesn't match the gauge's output it's really hard to tell which one to trust.

I'll probably mount mine on the firewall ziptied to a hard brake line or something like that. My sensor is mounted in the exhaust like this:

Then I'll run the rest of the cable through an existing hole in the firewall.

Same place I put mine has worked out pretty good over the years...
All the logs of mine I've ever looked at the Analog output has never matched
But it was always off by the same amount say the gauge read 11.5 it always read 12:0-12:1 I think it has more to do with where your gound is then anything. ...

 

[->PrOjEcTGS<-]

What WBO2 are you using? I thought the same thing on the ground deal. So, I moved the ground to the same as the ECU. It didn't help at all. I experienced the same inaccuracies that you did with the gauge reading about 11.3:1 at WOT and the logger reading at the ECU 11.8:1 - 12.0:1. That is unacceptable when I'm trying to tune for 91 octane pump gas and 25psi. Which one do I trust? The gauge or the output to the ECU?

 

[MY1GDSM]

What WBO2 are you using? I thought the same thing on the ground deal. So, I moved the ground to the same as the ECU. It didn't help at all. I experienced the same inaccuracies that you did with the gauge reading about 11.3:1 at WOT and the logger reading at the ECU 11.8:1 - 12.0:1. That is unacceptable when I'm trying to tune for 91 octane pump gas and 25psi. Which one do I trust? The gauge or the output to the ECU?

The Same AEM Uego... I've also tried to move the ground (not that hard)but the output has always been still offset...compaired to the log,I've gone through the trouble a few times to turn the car over with out starting it(to go rich) to record what the voltage output was vs. the gauge as it went rich... I would just get an Idea where you are at as far as High/low for the output vs the gauge(trust the gauge)and then when you know what your readings are Realy vs the Logs you'll have a better Idea where you need to be...pump gas? No E85 where your At?

 

[->PrOjEcTGS<-]

I despise E-85 and will do anything not to run it but let's not get off topic. While it's a great fuel it is lacking in some areas. I used it once as a mix with the 91oct but quickly went back to straight pump.

 

[bling5tatus]

My lc-1 is right next to my ecu... the wire for the sensor was long enough to run through the firewall and to the exhaust pipe. I just didn't like putting an instrument like that in the hot engine bay even if it says it's ok to.

 

[->PrOjEcTGS<-]

To the OP are you using an AEM UEGO or the LC1 in your profile ??

AEM UEGO is v * 2 + 9.3 for afr. Their white papers are totally wrong.

Look UP at post #17, I've got the LC-1 now and currently just have it simulating a narrowband. I'll burn WBO2 chip today and change the voltage output though and see how it works.

Well, I took your advice because I really WANT this to work. I sold the AEM UEGO and bought an LC-1. It should be here in a couple days. You're right the UEGO is very lacking in it's abilities.

 

[We're on Boost]

My lc-1 is right next to my ecu... the wire for the sensor was long enough to run through the firewall and to the exhaust pipe. I just didn't like putting an instrument like that in the hot engine bay even if it says it's ok to.

aaaaaaa-men to that bro!
According to Innovate tech support, the only reason for the short wire from LC1 to sensor is fear of electrical interference. I think I'll call them back and ask them if they can do a custom one for me with a long wire with better shielding on the wire or ferrite beads or something.

Where did you put the sensor through the firewall? or floor? Did you make a new hole?

Gary

 

[Maglin]

I ran this several years ago with a LC-1 and XD-16 gauge. My gauge was always spot on but it's also digital not analog. I first tried out the NB simulator and hated it termensily. I was using a Ostrich so I just changed my output on the LC-1 and the code on the eprom and restarted the car. Was pretty decent OTB but I did change my sweep points. You don't want them to narrow. If it's to narrow it will constantly overcorrect and make your afr swings worse. You can't expect a rock solid afr at idle. Cruise should be within a .8 AFR swing. I also had my LC1 located just under the firewall and mounted the controller on the firewall.

And to the OP. Don't try something find it doesn't work and make a off the hip judgement call and then write a "review" saying it shouldn't be used for whatever you are tring to use it for. The EPROM ECU in the 1G happens to use the same processor at the MS1's do. It's pretty robust and can handle a decent amount of instructions before really slowing down. Oh I also was running double width maps, stutter box, NLTS and a few other things that I did on my own.

Also something to note. Your large AFR swings can also be caused by having your injector deadtime off by a decent amount. The larger the injector the more you'll notice this. And my stock NB o2 had a afr swing of like 13-16.5 at idle. I got it to 14.2-15.1 at idle running 1000cc injectors with .8ms of ipw. I couldn't get it any better cause any lower the injector just wouldn't be squirting any fuel. You generally want at least 1.5ms of ipw at idle for a decent idle fyi which you will not see with large injectors.

The position of the O2 really isn't going to make a difference that you could even feel and unless it's past the firewall you probably wont even see it on a log.