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Why does it run worse with Autotune running??

AaronBND

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I have the MAP switch hooked up to my sled and anytime I flip the switch to turn the Autotune on it runs like crap while its flipped on. Anyone else experience this? I'm about ready to give up on it. I bought it to fine-tune and play with, but it is more trouble than it is worth IMO.

Aaron
 
What a/f ratios are you putting in? I use mine to fine tune my bb m7 and it worked very good.
 
Well if I understand correctly, it runs off the current map until you accept the trims it creates? Mine will run ok off the before map and then when I flip the switch to autotune it runs bad even before I accept the trims it makes. I don't think it auto-adjusts anything as you go with it on. Right?
 
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No you have to put in what a/f raitio you want the sled to run at. The trim numbers are the difference between your current map and the a/f ratio numbers you put in and want the sled to run at. Go to the dynojet website it can explain how to setup the a/f ratio numbers. Here is a screen shot of what it should look like.
auto.jpg
 
I understand all that. I have AFR targets programed in. What I am saying is just because you flip the switch to autotune doesn't mean it is "auto-adjusting" as you go. It is only creating trim numbers for you to accept if you choose to do so. As soon as I flip the switch it starts running rough.
 
Yes as soon as you turn the auto tune on it adjusts the tune up to what A/F ratio you put in. It only changes the map if you accept the the trim numbers. If it runs that bad your either off on your numbers or the o2 sensor is bad.
 
Auto tune has to be used very smoothly. It has to to stay put at given rpm and throttle position. That's why it doesnt work very good at lower rpm and throttle positions. Best way to use auto tune is to turn on above 70% throttle and above 6500 rpm. Data logging is the best way to tune by afr. Record for a while, then use those numbers to trim your fuel settings. By the way if you have the accelerator pump feature turned on every time you move the throttle with auto tune on it starts with a false reading because that feature gives extra gas anytime tps moves.
 
I just got off the phone with PowerCommander to ask them about this. When you flip to autotune it does run off of the afr numbers you have loaded as stated above by 2005m7. They said what is probably happening is down low like hd4rob said it can get some weird air feedback's in the pipe and be all over the place. He said the best thing to do is put all "0's" in those areas on the afr tables so it doesn't try to tune that range. In my case it is up to about 4500rpm's. I will do that and see if it helps. Thanks for the posts guys. Had me baffled!

Aaron
 
I think there could also be probe location that can play a role in this. Speedwerx installed my bung when I purchased the pipe and I've been using that location (approx.) with other sleds that I have tuned (bung location is in the fattest part of the pipe, a couple of inches away from the pipe temp sensor @ approx 10* off TDC of pipe). I can't get AFRs any leaner than 14.5 to work, even at 14.5 idle will go up 3-400 RPM and when the engine is real warm will take time to idle down. I have found my 4-5,000 RPM a little lean on throttle up and a little fat on hold back, I stopped trying to autotune this and just doing small adjustments (I think this is where the LCD would play a BIG role because one would know both throttle position and AFR for that cell).
 
Thanks for chiming in Terry. I put mine down in the skinny part beside the coolant bottle leaned back about the 10 o'clock position so the hood clears. I have always had idle issues even w/o the autotune. Sometimes it idles higher than it should and also it takes a few seconds for it to come down sometimes like you said. Have seen a couple threads about that on here. I think that is PCV software related or something weird myself. Anyways, I made all the cells from like 4250rpm and down zero's for now and will keep playing with it.
 
Aaron it's interesting you bring up a potential software problem because right now I am trying to sort out a new PCV on a 2010 M8 that is having issues and it appears there could be a firmware issue. (power commander term for software in the PCV) It seems power commander might be the Microsoft of the after market tuning products and the PCV seems to require regular firmware up-dates, the latest firmware is V0.1.8.5, the brand new PCV I'm working with is running V0.1.4.0 and the tech at power commander says that's such an old version that I probably need to send the PCV in to them to have it up-dated. I have been spending a lot of time trying to get the firmware up-date off of Power Commander with no luck, I was able to up-date my PC software to the latest version, however I believe one needs Adobe Acrobat in order to download the firmware and that is an issue if one doesn't not already have it.

What we have found on the new PCV we have been trying to set-up on the 2010, is a lean condition and surging as well as no throttle....it seems to work fine above 5,000 RPM. This problem will not be there when one first starts the machine, we were even able to run around the field for about 10 minutes and set-up the autotune but then it starts (almost like it's a temp thing, like when the machine gets warm it starts acting up). The first thing we notice is throttle hesitation (lean), then the idle is fluctuating approx 4-500 RPM (2,200-2,700 RPM) at idle, then she won't take throttle at all. We've had this happen on 2 different PCV on this machine, with and without the autotune connected, fortunately the machine can operate without the PCV connected so we have just disconnected the PCV and ran the sled. We were trying to clean up the bottom end of this particular M8 at it was very rich coming downhill (always had been) etc and at the sametime lean due to reeds, air intake and can. When the PCV was working it worked well, however it's been a pain in the a$$.

We have even talked to the dealer about reflashing the 2010 ECU to the up-dated 2011 spec, the dealer gave it a try but to no avail, kind off pi$$e$ me off abit, Cat has had EFI for almost 20 years and they still can't seem to get mapping right. That's my rant, they didn't get my 09 HCR right either.

My long winded point here is maybe check your firmware numbers, you can do the by plugging in your PCV to your PC, click on "view"'(top left), click on ''device information" and you will see a firmware code in the list. Maybe there's a firmware issue that needs sorting out.
 
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I have done a couple updates on it already with the last one being only a couple months ago. The software side on the computer and the firmware side on the box. Never any issues with upgrading, but their are definitely little issues I have seen with the box like the idle issues and also wanting to die sometimes after long pulls when you turn out and are pointing back down hill (yes I have fuel added lower for throttle dive-off). I really just wish someone could get the "fuel box" thing right. I just don't know if it is the box companies or the arctic cat ecu side of things. I have tried them all many times and they all have their own issues. I still like both the Attitude and PCV, and the PCV does the best at temp and altitude adjusting day to day, but it shouldn't be so hit or miss with them. It's almost like the Cat sleds are all different coming off the line. Some guys running the exact same sled and mods have one issue and other guys have other issues. Weird! The hardest part is like you say......is it the box or the sled? swapping components sled to sled is the only way of knowing.
 
"What we have found on the new PCV we have been trying to set-up on the 2010, is a lean condition and surging as well as no throttle....it seems to work fine above 5,000 RPM. This problem will not be there when one first starts the machine, we were even able to run around the field for about 10 minutes and set-up the autotune but then it starts (almost like it's a temp thing, like when the machine gets warm it starts acting up). The first thing we notice is throttle hesitation (lean), then the idle is fluctuating approx 4-500 RPM (2,200-2,700 RPM) at idle, then she won't take throttle at all. We've had this happen on 2 different PCV on this machine, with and without the autotune connected, fortunately the machine can operate without the PCV connected so we have just disconnected the PCV and ran the sled. We were trying to clean up the bottom end of this particular M8 at it was very rich coming downhill (always had been) etc and at the sametime lean due to reeds, air intake and can."


It sounds like you need some more time figuring out what the power commander is capable of before just putting it on a sled as a catch all.
You can take away that lean hesitation on the bottom by setting up the accelerator pump feature. You can also tune for water temps by splicing into water temp wire and plugging into PC V. Auto Tune is not that good of a feature on two stroke machines. If you want to use at lower rpms you need a throttle stop and consistent riding conditions. One thing you could do for your over rich coming downhill but to lean otherwise is run a two position map switch. Flip or push while coming down hill to lean out bottom. Best thing for trial and error is if you have the LCD screen is to use your infield tuning feature to adjust your fuel trims. Auto tune will not get your sled to idle either. If idling were you say it is, start by adding 5% fuel at 0% throttle from 100rpm up past were your current high idle is, don't worry about were your afr is. Keep adding fuel till your idle is were you want it.
 
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Just wanted to up-date on what we found with the 2010 we were tuning, turns out the ECU is having a problem and the power commander magnified the problem. The ECU is not showing any codes, seems to run well enough, however is now starting to show signs of the symtoms we were seeing while the PCV was connected (or it could be we are a bit more aware)
 
Makes it tough to know if it's the machine or the PCV box when having tuning issues. I am getting my PCV map dialed in better for my '08 ecu, but am still a little dirty throughout. I threw the Attitude on for today's ride. I would rather run the Attitude if I can make it work. I like it's simplicity and easy adjustment on the hill. Glad you got it narrowed down.
 
Check and make sure your ground on the auto tune is making good contact. Just a suggestion :)
 
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