ZoomZoom77

iTrader: (10)

I was just trying to trouble shoot my BAC valve as it doesn't seem to be working and I noticed that I had the valve frequency set to 15Hz in tunerstudio. When I try to change this setting I get a warning from tunerstudio saying that valve frequency must be less than 15Hz. I have been following Aaron Cake's write up and it says to set this to 78, and the other posts ive seen have all had the valve frequency set between 50 and 100 so why wuld tunerstudio limit me to 15?

I have double and triple checked all my wiring including the direction of the diode in the harness. I am running MS2 V3 board with tunerstudio V1.004. I have the BAC wired using the green F-idle wire as recommended in Aarons write up

Anyone have any insight into why it might be limiting my options for valve frequency or why it might not be working? Thank You, Daniel

ZoomZoom77

iTrader: (10)

Ok, so I think I have this one figured out but would still like some confirmation. After reading through some of the MSextra forums I relized that the number entered into TunerStudio is multiplied by 30.5 to get the actual Hz. So in this case I would either want to set this parameter to 2 or 3 correct? Would having this set to 15 (457.5Hz) have hurt anything or would it just cause the valve not to work properly?

Why would TS use this multiplication factor instead of just allowing you to enter the desired Hz directly into the block,as it seams to really limit your options? I may be way off here but that is how I understand it right now... please correct me if i'm way off base. Thank you.

muythaibxr

Tunerstudio doesn't limit the frequencies, the firmware does.

The reason is that we're doing the PWM in software, and the duties supported are only the 30.5 * x (x is the number you set) frequencies. We could change TS to display the actual frequencies, but it has never been brought up as an issue with other users to my knowledge.

Ken

ZoomZoom77

iTrader: (10)

Thanks Ken... now that I know that is is a multiplication factor it shouldn't be a problem... I just overlooked it before. Would having this set to 15 be enough to keep the valve from working? Would it hurt anything? Would you recommend setting this to 2 or 3? Sorry for all the questons, just want to make sure I have this right before I try it again. Thank you, Daniel

muythaibxr

15 wouldn't keep it from working, but it would make the resolution really crappy. The higher you make the frequency, the more the commanded duty has to change before it causes a change on the valve itself.

Ken

ZoomZoom77

iTrader: (10)

Thanks again, I will try it set to 3 for now and see how it goes. I really appriciate all the help and I will report bac after trying it tomorrow.

ZoomZoom77

iTrader: (10)

I really feel pathetic having to ask for so much help but I am not making much progress on getting this thing to restart reliably. I have tried to changing cranking pulse, idle pwm duty, cranking pwm duty, ASE and the fuel in the VE map and have not been able to get it close to being able to restart reliably.

It has never started without heavy throttle input as you can see in the logs. I know this is because it is engaging flood clear mode during cranking, which means I should pull fuel out... but I have pulled a substantial amount of fuel out of cranking, VE map, and ASE and it doesn't seem to make it much better.

After changing the settings on the BAC valve it seemed to be a little better but not much. Do I still have way to much fuel in my settings? It still will not even think about starting on its own (without throttle input).

on top of the restart issue the idle is very irratic and needs to be reset almost everytime the car starts. I have been setting it high because trying to set it around 1000 just results in it dying or not holding an idle on the next start.

If you could please take a look at the datalogs I would be very greatful. Thank you, Daniel

ZoomZoom77

iTrader: (10)

Here is my MSQ as it stands right now... this is the result of the above attempts starts and all the others from that day. In this msq I have lowered my cranking pulse, pulled fuel from the start up section of the map and decreased my ASE percentage. Please tell me what you think.

muythaibxr

Engaging flood clear mode during cranking means that your TPS is showing a higher value than the flood clear TPS setting. Did you calibrate your TPS?

Are you using closed loop or warmup only idle speed control?

If this is the first time you're starting the engine, you should be using warmup only. I would not use closed loop until you have the engine idling properly, etc...

Have you checked the timing with a timing light?

Ken

MMoore4545

iTrader: (7)

Anything over 70% of tps voltage activates flood clear during cranking so even if your tps is calibrated close, having to depress the accelerator to get the car started could still activate flood clear. If I'm reading this right he is using the accelerator pedal to get the car started.

Few quick questions

1. Has this just started happening as the weather got colder? or is this the first time you're starting the car on megasquirt?

-Having to floor the car to start it (even with fuel cut) indicates a mixture problem. The air/fuel eventually/sometimes balances out and things start.
-If it is the first time starting it, and you're having to floor the throttle to get it to start, try adjusting the throttle plates at the throttle body. By adjusting these we can see if it is an air issue.
-If the car has started reliably in the past, I'd undo all of the adjustments you made to your VE table/etc and adjust the throttle plates, my vote is that your BAC is dead.
-Don't have my tuning laptop at school, so I can't see your logs/etc but If the car hasn't reliably started ever, and this is a first start issue I'd probably undo a lot of your changes back to whatever writeup/setup you used.



2. Did you modify the v3 board as per Aaroncake's write up? (replaced Q4 with a TIP120 and remove Q20, D8, and jumper R39?) The V3 board cannot natively drive our bac valve. only the v3.57 board does.

3. Do you feel your bac valve working? Literally. They tend to vibrate, maybe your bac valve is in need of cleaning/replacement.

-If I didn't have my frequency multiplier set to 3, like when I first plugged my bac valve in, it audibly hummed on 1 and 2. (tested 3 of them before I realized it was the value.)
-If you don't feel it, test it as per fsm.

4. As Ken says keep it in warmup mode right now, check your timing too once you get it started/warm


5. Finally did the engine run before you went to megasquirt?

ZoomZoom77

iTrader: (10)

Ken, the tps has been calibrated (although it does not always return to exactly zero) and I am definitely engaging flood clear mode during cranking (I have to rapidly cycle the throttle between normal cranking and flood clear mode to get it to try to start). My flood clear setting is set to 75% throttle right now.

I am still using warmup only idle control as I have never been able to get the car to start reliably. It will idle pretty smoothly but the idle does not always return to the same rpm on different starts. I have set the timing using both the VE table and the throttle plates. I have adjusted everything to idle smoothly at the lowest possible vacuum as per Aarons write up, but the next time I start the car, the idle usually doesn't return to the same RPM and i have to repeat the process over again.

I have checked the timing with a timing light and set it to -5 degrees (set it on the mark with the megasquirt set to -5 fixed timing).


MMoore4545, you are reading it right, I have to press the throttle, engaging flood clear mode for it to even attempt to start and even doing this is is a very slow labored start.

The car has never started reliably using the megasquirt. I got it to start for the first time about three weeks ago and have been trying to get it to start reliably ever since.

I have been quite suspicious of the BAC too as it seems like all my mixtures during cranking and warmup are very rich. I figure it is safe to assume that Aarons wright up is not this far off, and I now have everything set just as he has described so the BAC seems like the most likely culprit.

I will try to verify operation of the BAC valve tomorrow. Can I turn the BAC valve on with the "idle valve test" feature so that I do not have to be cranking the car for the BAC will come on?

I will definitely be keeping it in warmup mode until it will start reliably and i have checked my timing and operation of both coils so i know that is not contributing to the problem

Unfortunately I cannot verify that the car started before the megasquirt as I am working from someone elses botched build. I know that Megasquiting a non-running car is not ideal but given the condition of the wiring harness and my plans for the car it seemed like the way to go.

Thank you for all your help. I will test the BAC tomorrow and report back.

ZoomZoom77

iTrader: (10)

I tested the BAC today and it checks out according to the FSM. I am still going to try to find someone to crank it over while I feel/listen for the humming of the BAC operating, but I don't think it's the problem

ZoomZoom77

iTrader: (10)

Anyone had a chance to take a look at the logs yet? Im trying to get together a sound plan before I try it to many more times.

Does it look like I still have to much fuel in my settings, what is te best way to get close? Thank you, Daniel

ZoomZoom77

iTrader: (10)

Well did a little more testing on the BAC today... It wasnt operating properly at all. Although it checks out according to the FSM, when I set the valve frequency to 2 and listened for the hummm I couldn't hear anything, when I went to pull it off to see if the valve was moving at all I bumped it against something and it started working. Sure enough everytime I turn the key on it isn't operating until I hit it with something. When I get another one on there I will let you guys know how it goes, thank you all do much for the advice.

ZoomZoom77

iTrader: (10)

Been away from the car for a while because of the holidays but i Have been working on it for about the last 4 days straight with no success whatsoever. I confirmed that the BAC is operating. I pulled it of and can see the diaphram moving as it should. It also seems to respond to inputs in tunerstudio so I am assuming it is working properly.

Over the last 4 days i have tried everything I can think of and cannot get close to any kind of reliable start. Sometimes i can get it to fire up and idle but it is a rare occasion. I have tried changing the Cranking pulse width to both the values specified in Aaron cake's write up and the ones recommended in the megamanual and have tried just about everything in between. Some times I can get decent response on cranking and sometimes i get absolutely nothing.

I have changed warmup up and down in a huge range and have tried ase at everything between 0% and 60 percent.

Even if a setting seems to work once it will ever provide anykind of consistency even with identicle startup conditions. I don't understand why everything is so inconsistent.

I have a library full of logs and MSQ's telling me almost nothing. Hopefully someone can see more of a trend in them than I have been able to. Logs and MSQ posted earlier are still fairly accurate as most of my efforts since then have seen almost no success.

I have included 5 more of more recent attempts (today) All of these data logs were conducted with the Cranking pulse width percentages recommended in the megamanual. I will include a MSQ of how the tune sits right now.

Someone please help me save this project. I was so excited about this system and it has turned into an absolute nightmare. After fighting with it for about the last three months i am on the verge of parting out the car. someone please help me keep this thing in one piece.

ZoomZoom77

iTrader: (10)

Here are my most recent MSQ's

The fist is how it sat three days ago when i started messing with it again. This has a roughly tuned VE map that will idle and run the engine.

The second one is an attempt to revert back to an older tune with the exception of using the Cranking pulse width % recommended in megamanual.

The third is how it sits right now.

Thank you for looking.

ZoomZoom77

iTrader: (10)

Something else that has been on my mind is why the recommended Cranking Pulse Width percentages are so much higher in Aaron's write up than they are in the megamanual. At close to operating temperature Aaron recommends a cranking PW% of 160 while the megamanual recommends 101.

Are Aaron's settings higher to compensate for the added air from the BAC valve? Are they richer to help with startup? should I expect to change these values a lot and eventually end up close to values recommended by megamanual?

Could someone post the values for Cranking PW, ASE and Warmup enrichment, from a running, starting, stock port 13bt? I would like to have something to reference so I at least know if I am in the ball park and I have had a lot of trouble veiwing the MSQ's that I have found online. Thank you, Daniel

Aaron Cake

iTrader: (1)

Because the cranking pulse, warmup, VE table, and all other fuel related functions are tuned to the specific engine. The examples in the Megamanual are just examples.

My base maps are set up purposely rich and conservative to try and guarantee that successful first startup on a fresh standalone. They are just a bit of a better example than in the Megamanual. But still an example.

In MS1 and earlier firmwares for the MS2, the Req Fuel value can just be 10MS, then all other values adjusted for it. 10MS tends to keep the VE table reasonable when dealing with rotarys that need a lot of fuel. In later firmwares, Req Fuel is used in calculations like accel enrichment, so it should be calculated properly using the function in TunerStudio/Megatune.

ZoomZoom77

iTrader: (10)

Even though these settings are rich they would normally start (and restart) a nearly stock 13bt correct? Since so far this project has been plagued by mechanical problems that have complicated the MS build, I'm thinking that maybe my focuss is in the wrong place. I guess as much as anything I am looking for confirmation that these settings, loaded into a healthy MS unit, controlling a healthy engine, would start reliably and at least get me tuning. If this is so then I am going to stop trying to tune around what is probably a mechanical problem and dig back into the engine.

The only things that I can think of mechanically that would likely be complicating the tuning are possibly leaky/damaged/clogged injector, a vacuum leak, or an irratic BAC valve (i have confirmed function so i know it isn't completely stuck).

Most of my problems seam to revolve around start up so I think I am going to go ahead and try to find a new BAC valve.

For a MS2 running the most recent firmware would you still recommend leaving the Req_Fuel at 10 for the innitial start up and later adjusting it to the calculated value and rescaling the maps once it running?

I am going to put all my settings back to the ones specified in your write up and again try to work form there.

ZoomZoom77

iTrader: (10)

I wanted to make sure the injectors were functioning properly and not leaking so today i pulled the intake manifolds and wired the injectors to the rails so that I could presurize the system and watch them fire.

The injectors do not leak and are providing strong pulses from both the primaries on cranking.

I also wanted to verify that I had wired the system properly and had not reversed the wires for the primaries and secondaries. They are wired correctly and everything seams to be functioning properly.

I am still on the hunt for a BAC valve from an s5 TII and once i get another one I will try it and update.

In the mean time I want to keep testing any other possible problems. When I had the engine running and up to temperature I checked and set the timing as per Aaron Cake's wright up. The CAS has not been moved since then and my timing setting have stayed the same so I'm pretty sure timing is still good. While I had the timing light on it I also verified that both coils were firing and they were functioning as they should.

What else should I check? I'm going to go back into my settings tonight and set everything back to What is recommended in Aaron Cake's wright up and start from a clean slate again once I have the new BAC

ZoomZoom77

iTrader: (10)

I just got done going through all of my Settings in TS and setting them back to the values specified in Aaron Cakes wright up. Although almost everything is exactly the same as the wright up, I would appriciate if someone could give it a look to make sure I haven't missed anything. I am worried i might have overlooked or missunderstood some of the parameters because of the slight differences between the wright up, and the options in Tuner Studio.

Specifically if someone could look over my trigger wheel/ ignition settings and let me know if these look right for a modded CAS (cut out 2 opposing teeth and am not running the second VR)

The only things that i was confused about when going back through the setting were:

Map Sample Window (deg) ..... set to 10
Map sample Angle (deg) .... set to 90
no. sample events .... set to 1

Should all these just be left at the defaults or should I be paying them closer attention.

Also I have the lower accel enrichment threshold set to 8000rpm to dissable it. Will this effectively dissable AE or do I need to change somethign else as well?

Thank you, Daniel

muythaibxr

They can safely be left at the default for now. You may want to tune the MAP sample angle a bit if your MAP signal is too noisy.


That won't disable anything. That will actually just make it give you the full AE amounts through the whole table.

The best way to disable it is to set the MAP and TPS accel thresholds to extremely high numbers, and/or to change the amounts to 0.

Ken

ZoomZoom77

iTrader: (10)

Muythaiboxr, thank you for your reply, I have returned the accel enrichment back to acceptable values and have raised both the MAP and TPS accel thresholds to 1000 to dissable AE.

I found a BAC and it should be on its way soon. Does anyone else have any input on settings or other possible complications?

If you have set the timing and checked for spark on all plugs can you pretty much rely on the ignition settings and equipment to be good. Any incorrect settings in the timing or trigger wheel settings would most likely keep me from properly setting the timing right? I just don't want to rule anything out.

ZoomZoom77

iTrader: (10)

Ok, so I finally got the BAC in and it did seem to help, My cold starts got a little faster, and a little more consistent (still kind of have to pump the throttle to get it going but it will start). Today i got it to start about five times at varying temps from cold (ambient temperature 65) to about 155 degrees. However when it gets to full operating temperature it refuses to fire at all. At full temp I have moved the required fuel around over a wide range and have tried setting it high and playing with the throttle to try to get it to start but nothing seems to get it to fire. I pulled the plugs and cleared the cylinders regularly and checked the plugs which did not seem to be overly saturated with fuel.

With absolutely no feed back from the engine how can you tell whether you need to add or subtract fuel?

what do you do if you absolutely cannot get megasquirt to work. Is there a shop within any reasonable distance of Beaufort South Carolina that specializes in or even knows Megasquirt? I have been working at this for almost four months now and I don't really know where to turn.


I have included my most recent datalogs. The frist three are the first few starts and a little bit of the engine idling. The last one is trying to restart the car with the engine warm.

Anything you can tell me would be greatly appriciated. Thank you, Daniel

ZoomZoom77

iTrader: (10)

anyone? please