Another MS conversion, Progress, at last. Options

[JimN73]

OK. Thanks, James

[JamesM]

I just took a quick look over you latest log file and it looks like you are heading in the right direction, you can already see that the area in the table that you are running for various RPMs has alraedy started to move down slightly. What this means is that you need now need to tune these areas of your table as well as you were not previously using them.

A couple questions came to mind when looking this log over.

1. Have you verified your settings everywhere (ECU, tunerstudio, and megalogviewr) for your wideband O2 sensor are correct? The reason I ask is that you say you are seeing richer then your AFR targets in your logs while when i look at them i see you are still on the lean side. It may be that my settings are wrong for viewing your logs, but Mark said you are using the AEM setup. Newer versions of the AEM setup run as linear by default and i have my log view set with that assumption. If i change my settings to view it as nonlinear then i see the same thing as you where it looks rich. The default for the sensor should be linear though, so i suspect unless your sensor defaults were changed you may be looking at the wrong values for your AFR whle tuning (which would cause some big problems)

2. Is your throttle position sensor calibrated properly? I see at one point you ran the engine up over 5000 RPM but at no time to do i see the throttle position sensor register more then 60%

Also, any chance you could post your latest MSQ used with that log file? Really need to look at them together to see what is going on.

Thanks
-James

[JimN73]

James, I will defer to Mark for the calibration questions.

The date stamp on the tune file is later than the date for the log file. I've updated the req_fuel so I'll retune and relog this morning.

[JimN73]

I just took a quick look over you latest log file and it looks like you are heading in the right direction, you can already see that the area in the table that you are running for various RPMs has alraedy started to move down slightly. What this means is that you need now need to tune these areas of your table as well as you were not previously using them.

A couple questions came to mind when looking this log over.

1. Have you verified your settings everywhere (ECU, tunerstudio, and megalogviewr) for your wideband O2 sensor are correct? The reason I ask is that you say you are seeing richer then your AFR targets in your logs while when i look at them i see you are still on the lean side. It may be that my settings are wrong for viewing your logs, but Mark said you are using the AEM setup. Newer versions of the AEM setup run as linear by default and i have my log view set with that assumption. If i change my settings to view it as nonlinear then i see the same thing as you where it looks rich. The default for the sensor should be linear though, so i suspect unless your sensor defaults were changed you may be looking at the wrong values for your AFR whle tuning (which would cause some big problems)

2. Is your throttle position sensor calibrated properly? I see at one point you ran the engine up over 5000 RPM but at no time to do i see the throttle position sensor register more then 60%

Also, any chance you could post your latest MSQ used with that log file? Really need to look at them together to see what is going on.

Thanks
-James

James, here's the latest and greatest.



https://www.dropbox.com/sh/p593bw6iyebgwjn/bANp3X25ic

[JimN73]

If you opened the files that I did this morning, please look again. they are changed.


https://www.dropbox.com/sh/p593bw6iyebgwjn/bANp3X25ic

[JamesM]

If you opened the files that I did this morning, please look again. they are changed.


https://www.dropbox.com/sh/p593bw6iyebgwjn/bANp3X25ic

Just took a quick look but, nice! Thats what I am talking about! This log is looking much better! The Ve table still has a couple spots that need to be massaged out but its just spots now rather then everywhere. Overall it doesent look like you are lean under load any more which is a very good thing. From what i see its a couple little problem spots and then just fine tunning from here.

Curious to know what your impressions of driving it are at his point? Is real life matching what i see in the logs?


Ill give it a more serious look when i get home tonight and detail what i see, but i am guesing you might even have it sorted before then.

[McMark]

I never hooked up the AEM to a computer and never changed anything. I suppose it would be worth verifying the settings.

The TPS can just be recalibrated using the menu option. It may have varied after the ECU swap.

[JimN73]

Thanks, Mark. I'll do the TPS later today. I think I read that the AEM wideband doesn't need calibration. I just read a suggestion that if you unplug the sensor, you should get a reading of 14.7.

James. The car is much better. I may have introduced new and hopefuly a minor issue.

I dialed in some accelerator enrichment, similar to what had been entered originally. I don't know what the rates (%/second) mean, so what I've done is probably counterproductive. The effect is bucking every now and then at about 2000 rpm. The log 's with today's date shows it at 7779 seconds, and a few places further on. The tune is there, too.

Perhaps a short dissertation on Accelerator Enrichment would help those of us who are following this.

The other thing I've noticed but haven't done anything with is rough and lean running from cold start thru the time the WUE shuts off. Again, I'm not really sure I understand what the entries in the graph do, or what other things effect WUE. So, probably another lecture.

thanks again for your time.


https://www.dropbox.com/sh/p593bw6iyebgwjn/bANp3X25ic

[jpnovak]

I opened your msq and see that you are using TPS enrichment for AE. The lowest row is set at 7 %/sec. This basically means that any throttle movement is going to trigger AE and you will bog down rich. then you go to fuel cut and back into a cycle - hence your bucking problem.

Raise the value to at least 100 %/sec or some higher threshold to prevent it from kicking in unless you want it.

Now, James made the best comment above. Completely turn off your AE for now. yes, the car may hesitate slightly when you mash the throttle but you have to tune the VE table before adding AE. AE is only for smoothing throttle transitions, not for delivering fuel. With a properly tuned VE table, running speed density (MAP) based fuel loads you should need very little AE to compensate for throttle transitions.

What is AE? AE is the electronic equivalent to accelerator jets on carbs. They squirt a little fuel to help the engine compensate for the large rush of air when the throttle is opened. Generally the engine will quickly spike lean and then recover as the fuel delivery catches up. On carbs you have to wait for the vacuum to build and suck fuel up an emulsion tube and then spill over into the carb tract. On EFI, your injectors only get what fuel the computer tells them to squirt (as measured in timed pulse widths). the MAP signal changes nearly instantaneously and the fuel delivery will compensate, however, you may sometimes have too fast of air pressure change and you have to add a little extra fuel. This is what AE is for.

Once you have your VE table running well, then you can set the warmup enrichment (WUE). Once the car is started and while it is still cold you have to watch the temperature/enrichment curve. Add as much fuel as you need to keep the car running smooth at idle while warming up. The curve is not linear. If you are lean at certain temperatures, just add more % fuel enrichment only at those temperatures.

Glad you are starting to understand that the car must be tuned to run properly. Its really no different than bolting on a carb with the wrong jets - it will run like crap until fixed.

[JimN73]

thanks for the explanations, Jamie. I know what's going on, but I don't know what the fixes mean or what their effect will be.

Either this is starting to make sense or I'm losing my mind.

[jpnovak]

Jim,

The %/sec is how fast the throttle opens. the time pulse that fills in the other column is the pulse width in ms that determines how much fuel is squirted. The faster you open the throttle, the more air dumps in, the more fuel you need to squirt to account for the extra air.

I usually have a maximum of 0.8 ms when you have maximum AE.

Usually, I do not run TPS acceleration but relay on MAP_dot AE. MAP_dot is the change in pressure similar to the $/sec its units are kPa/sec.

If you are using TunerStudio, you can open the AE Wizard. The graphs on the top will have a bouncing cursor showing TPS_dot or MAP_dot value. Make sure that the trigger value (lowest point on the graph) is above the "noise" value during normal running.

Then blip the thottle a few times. Try to be consistent and hit a value. Watch your AFR. Adjust the pw higher if you see large lean spikes. You are aiming to add fuel until the AFR stays constant for small, med, large and WOT type throttle blips.

Again, do this after your VE table is well tuned and you should not have much AE to add.

[McMark]

Doubt check (or just reset) the AFR calibration.

[JamesM]

Sorry have not had much time to respond, developed a suspension issue with my autox car that I need to resolve before the first of the month.

On the AFR calibration, I am guessing we are good there, the last logs I checked out were making more sense. I suspect you may have just had a incorrect setting in your log viewer.

As for the Accel enrichment, I can't stress this enough, just turn it off for now. You don't need it and it is just going to get in the way of tuning the Ve table. Once your car is running great and you really want to FINE tune things then you can start slowing adding in some AE, for now though just turn it off and forget it exists.


Just keep tuning the Ve table for now, looks like you are still a bit lean just about everywhere down low especially in the 1800-2300 RPM bins, from what I see I would guess you are coughing pretty bad when getting back on the gas after decelerating into that area (this is an issue with your Ve table, not a lack of Accell Enrichment). Also looking pretty rich up top. I would say adjust your AFR targets to where you are not going richer then 12.5:1 anywhere, and then lean out your top end to match, that should get you some more power up there.

Any adjustment to your Ve table right now should be done with your engine fully warmed up. It is a lot easier to adjust your warm up settings once you are happy how your table is running. My process for adjusting the warm up settings is first to know at what AFR your car normally idles, then wait for a cold day and with your engine as cold as it gets, start it up and once your after start enrichment has finished go to the warmup wizard and adjust the % for your current temp bin until your are hitting your normal AFR. As the car slowly warms up keep adjusting the associated bins so your car stays at its normal idle AFR through the entire temp range. This should at least give you a good place to start and from there you can tweak it to your liking. This usually takes some time to get right as you really only get one shot a day at doing this.

For now though your focus should still be on the Ve table.

-James

[JamesM]

I dialed in some accelerator enrichment, similar to what had been entered originally. I don't know what the rates (%/second) mean, so what I've done is probably counterproductive. The effect is bucking every now and then at about 2000 rpm. The log 's with today's date shows it at 7779 seconds, and a few places further on.

Just took a quick look at the latest log and that issue at 7779 does not appear to be related to your accell enrichment change, in fact i would guess that it is not related to your tune at all. You may want to have Mark take a look at that one in person as i cant see all the symptoms for that problem in the logs, not sure if what i am looking at is the cause or just a symptom. If i was to guess I would say it could be electrical noise or a problem with your tach input signal, but there could be some external factor as well that i dont see in the logs.



-James

[McMark]

Can't think of anything that would cause that. I'd need to see something more repeatable to even begin to diagnose that.

[JamesM]

Can't think of anything that would cause that. I'd need to see something more repeatable to even begin to diagnose that.

I aggree, its a strange one. Without experenceing it in person I could not say for sure. From the logs it does not appear to be missfiring as the AFR is rock solid through the rough spot, but if the car is bucking then i would think that something is wrong with how the fuel is igniting, but again the AFR is not looking like anything is wrong with the burn during that time.

TACH is registering ~300-400RPM osicaliations within 5/100s of a sec which makes me think it is a signal/electrical/noise problem. This might be causing the spark to occur at the wrong time due to MS not knowing the correct engine speed, which then causes the bucking.

Could you describe the bucking more in detail? Is it just a couple jolts or is it sputtering the entire time the noise is occuring? Any popping out the intake or exhaust?

Also, been wondering this a while but keep forgeting to ask, where are you pulling your MAP signal from?


-James

[JimN73]

MAP Sensor is on the inside of the fender, hose about 2 feet.

James, a bucking has been part of this installation from day 1. Earlier postings (perhaps from you) considered it 'noise'. In addition to the bucking, there seemed to be other problems that defied tuning correction.

Changes that were made over time seemed to help a little, sometimes only for a while. Ultimately, Mark bult a fully shielded harness and provided a new ECU.

It appeared that the new ECU took away all of the peripheral crap that was standing in the way of tuning the car. For the first time, changes in the 'tune' were reflected by changes in the way the engine ran.

I did autotune the other day and the buck seemed to be gone. Maybe I didn't drive in the range that it would show in. It hits at about 2000 rpm, sadly the engine speed that I use around town. I added back some enrichments and the bucking came back.

It's not consistent: sometimes I can get it to show at a steady rpm, sometimes on slight acceleration, sometimes not at all. Sometimes it's fairly violent, sometimes not so much. I really feel it at 2000 rpm but it's also sometimes apparent (much less violently) at higher rpm.

Over the next couple of days, I will drive the car and see what happens. I'll start by recalibrating the TPS and AFR. I'll strip out any EA and MUE that's there and I'll run autotune again.

Then I'll drive and log in the situations that bucking occurs.

VOODOO and black magic

I'll report back.

[JamesM]

Let me clarify, for the MAP sensor, where are you hooking the vacuum hose on your intake?

[McMark]

Stock 2.0 location on the intake plenum.

[JamesM]

Double Posted!