Experiences of a PCV with Autotune on a 2004 VFR800

[Guest GPM]

If your bike is a 2002-2005 model, you don't need gear advanced. "Basic Fuel" and "Basic AFR" are all you need, as only the 2006-2009 models have per-gear ECU maps. I had my '02 configured with "gear advanced" and it was AWFUL, because it just took ages for the Autotune to learn anything due to me shifting gears all the time (do note however that I have been trying to trim my way out from a zero map!!). However for 2006+ owners, it's a demon they have to live with until their system trims itself out over a longer period of time.

I found the exact opposite, my 2004 hated running with one autotune map, though it didn't have any major issue with one fuel map before the autotune. Anyway, it would run like absolute crap. Enabling map by gear fixed this right up for me. Maybe it depends on riding styles, or other mods? Or maybe there was more to the minor upgrades done in '04 then we know about. I will concede it took a while for trims to propagate (and even now, 6th gear doesn't have many changes because I don't ride in it often), but the difference was stark and immediately apparent.

The reason I don't like to enable my Autotune higher than the temperature where the thermostat opens, is that on cold days the bike will run right around that temperature and it's possible that your Autotune could flip-flop between being enabled and disabled. This would probably not feel good!

Coderighter and I have discussed this a little in this thread. I personally now think that you should set it some place below your normal operating temp. but not too far below that the autotune pollutes cells based on how much fuel the ECU calls for at lower temps (remember that the ECU makes adjustments based on engine temp - the autotune then picks up the changes in AFR and adjusts the trim map accordingly, so if you do a lot of shorter rides without the bike getting up to your normal operating temp you have a good chance of accepting some polluted trims).

That said, I don't think having it kick in at thermostat open is bad, it is a pretty safe place to do it, just keep in mind that you may need to run larger min/max trim settings to allow the Autotune to cope.

No, you don't want gear+cylinder. The Autotune is only monitoring two of four cylinders anyway.

What the powercommander will do by default is apply the percentage rich/lean values in each table to each cylinder individually.

For example, let's make up some numbers for a laugh and say that at X throttle and X rpm, the Honda ECU sends a value of "11" to cylinder #1 and "13" to cylinder #4. If your Powercommander has a value of, say, "10" for that same throttle and rpm location, then the result would be that cylinder #1 ends up being "21" and cylinder #4 ends up at "23".

So, only if the Honda ECU was making *wildly* different entries to each cylinder would a per-cylinder map have any value. Certainly your Autotune can't trim for it as there's only one autotune and four cylinders! A dyno tuner would have to put O2 sensors up *each* header pipe in order to tune for each cylinder, and even then your Autotune would only screw tha base map up because it's getting averaged values from two cylinders.

I've completely made up the numbers here of course, it's just an example.

Good explanation. I am going to go out on a limb here and say that the Honda map doesn't have different values based on cylinder (or rather, cylinder pair), but by having 2 O2 sensors it can make adjustments based on each pair in open loop mode. Unless you were trying to do something funky a cylinder pair's fuelling needs shouldn't be any different from the other unless there was some physical difference impacting on the AFR (eg. differences in the exhaust, blocked injectors, vacuum leak into the cylinder, etc).

The actual functionality is designed for Harleys, not Hondas. I wonder if that may in part because of the silly exhaust mods that some Harley owners perform (which may sound ear splitting loud, but probably screw up combustion - a lot of careful engineering goes into exhaust design!).

[Guest Sammy40]

Here's a spanner in the works.... I have an 09 model. Base map loaded on the PCV straight from Dynojet. Plugged it in...Runs as sweet as! No issues what so ever.Not using the Auto tune at all. Fuel econ is still good.Smoothed out the Vtec that's for sure :unsure:

[kaldek]

Here's a spanner in the works.... I have an 09 model. Base map loaded on the PCV straight from Dynojet. Plugged it in...Runs as sweet as! No issues what so ever.Not using the Auto tune at all. Fuel econ is still good.Smoothed out the Vtec that's for sure :pinocchio:

Nah not a spanner mate, probably more like the norm. It's just muppets like me with high mileage bikes bucking the trend I reckon!

[Guest Sammy40]

Here's a spanner in the works.... I have an 09 model. Base map loaded on the PCV straight from Dynojet. Plugged it in...Runs as sweet as! No issues what so ever.Not using the Auto tune at all. Fuel econ is still good.Smoothed out the Vtec that's for sure :pinocchio:

Nah not a spanner mate, probably more like the norm. It's just muppets like me with high mileage bikes bucking the trend I reckon!

LOL

[Guest GPM]

Nah not a spanner mate, probably more like the norm. It's just muppets like me with high mileage bikes bucking the trend I reckon!

Don't think milage has anything to do with it, I think its more muppets like us who just can't help but fiddle around a little more (and probably too much!). Otherwise we would have just left everything stock!

Speaking of muppetry, I have now installed a vacuum switch to disable autotune on decel - haven't tried it yet, and I don't think I will notice it until next week (I have this week off work so no commuting right now). I am still waiting on some new switches, as I want to also install a manual override switch as well, but once I have that and it is installed I shall put a write up on how to do it. Hopefully it will iron out the last few bugs in my Autotune setup!

(And once again, major kudos to Coderighter for his help with all this).

The only bad outcome from my latest bit of tweaking (and where that muppetry comes into play) is that my new vacuum gauge is indicating that my ongoing belief that I have some unhappy valves is correct. That means I see a valve check/adjust in my near future

[Guest GPM]

Ok, a bit of a type up of the effects of using a vacuum switch thus far - and already some new information to add to the PCV/Autotune puzzle.

I installed the vacuum switch, putting a T-joint into the MAP sensor vacuum line, hookup up the wiring as I had carefully planned (taking into account my yet to be installed manual switch) and took the bike for a ride to test it out. And, well, it ran like a sack of crap. I was very disappointed, over 30 minutes of riding along my local 'test track' (which covers local streets to highway, and lets me play from 3000 RPM to 8500 RPM in 2nd through to 4th gear - I tend to follow the same pattern every time to allow me to better compare results). When I got back home I hooked up the laptop to see where I had gone wrong. To my surprise, across 4 gears, there was not even 3 dozen trims - normally the trim map would be covered. I checked the vacuum switch, maybe it was activating at the wrong vacuum - not the problem. I then checked continuity across the two wires at the PCV, and, no continuity - there’s my problem. I checked continuity again across the pins at the vacuum switch, and, no continuity. Turns out despite my careful planning in my hurry to go for a test I forgot to ensure I had hooked the wires up to the right connectors on the vacuum switch.

Lesson number 1: Check your work!

Now for lesson number two. Really my inability to wire simple SPDT switches is not important, but what was in the map is. As I had wired it so that the switch would close over my decel. vacuum point (14.5 in-Hg), this meant the autotune was only active, and trimming, under deceleration where I hadn't fully closed the throttle (and as most of my hard deceleration is with throttle closed, this explains the small number of trims). Until now I had been working along the idea that the main manifestation of the decel. issue was abnormally high trims (ie. the Autotune was enriching the AFR as the vacuum on decel pulled air up into the exhaust from out the rear). Strangely, in my inverted vacuum switch readings I would guess only a 6th of total trims were increases in fuel - the vast majority were decreases, mostly big decreases (-5 to -7, my max enleanment setting). In retrospect this makes perfect sense - on decel manifold vacuum increases, this is what triggers the vacuum switch in the first place. The vacuum increases due to a lack of air, this is because the air supply (via throttle bodies) is suddenly restricted as throttle is closed. Combustion occurs as normal, end result passes the O2 sensor, but, because of the lack of air earlier, the Autotune sees a rich AFR and leans it out.

Now, if you are decelerating and stay in a particular PCV/Autotune cell for long enough, the vacuum will draw up air to the O2 sensor and it will see a too lean AFR - but that takes time (mind you, we are dealing with fractions of a second here, but enough time regardless).

Lesson number 2: So the decel issue has two main characteristics - first a major enleaning of the trim table cells as the system tries to cope with the sudden loss of air, and, given enough time, those cells may change to being enriched as the vacuum draws in fresh air directly.

Well, with that resolved (and the vacuum switch wired up correctly) I went for another ride along my test track. This time it was good - really good. It was only a 30 minute ride, so a bit premature to say it has solved all issues, but the bike felt very, very happy. I was careful to get into an upper rev range in different gears and then decel at part throttle, then not rev up there again (so I could see the results when I got home). Looking at the trims, it seems to have worked - those areas where I deliberately tried to cause the issue have trims +/-2%, which is pretty much nothing compared to what was happening before.

Also interesting was that in the cruise area at 2% and 5% throttle (which if you look at the graphs I have uploaded are pretty chaotic, and lean!) the trims have really richened up. I suspect what is going on here is that the decel issue had polluted these cells with lean trims as I normally am varying the throttle in that map area a lot during commutes. With the decel problem 'fixed' it can return to a more correct fuel adjustment. Just what I wanted to happen

Lesson number 3: Vacuum switches make for better Autotune generated maps!

More to come as I experiment more, and get more miles under my belt with the vacuum switch in place. I am curious to see how it will handle commuting...

[Popsrcr]

Ok, factory map, I have target afr and trim table. If I enable by gear for afr and fuel, I lose all afr targets. If I go back to basic, I don't get the targets back, I have to reload the basic map. Uh...???

[kaldek]

Ok, factory map, I have target afr and trim table. If I enable by gear for afr and fuel, I lose all afr targets. If I go back to basic, I don't get the targets back, I have to reload the basic map. Uh...???

Yeah it does that for everyone. The trick is to select the table you want, right-click and choose "select all" then "copy" and then when you go to gear advanced you paste that map into each gear's table. You need to do this for both the map and autotune target AFR tables unfortunately! The best way to do it is do one - fuel map or autotune - save the map, then do the other one.

[kaldek]

I am going to go out on a limb here and say that the Honda map doesn't have different values based on cylinder (or rather, cylinder pair), but by having 2 O2 sensors it can make adjustments based on each pair in open loop mode. Unless you were trying to do something funky a cylinder pair's fuelling needs shouldn't be any different from the other unless there was some physical difference impacting on the AFR (eg. differences in the exhaust, blocked injectors, vacuum leak into the cylinder, etc).

Actually it does - all the material you can find confirms that at the very least, the front and rear cylinders have different maps, probably due to heat differences. Does anyone know/remember if the 4th-gen and earlier models have different jets on the rear bank of carbs? If that's the case it would be for similar reasons!

[kaldek]

Ok, a bit of a type up of the effects of using a vacuum switch thus far - and already some new information to add to the PCV/Autotune puzzle.

I don't want to sound like I'm shooting you down in flames, but I just don't know if the vacuum-controlled switch is worth it. The Autotune trims FAST. And I mean REALLY fast - my tests with the bike running on the centrestand have shown it will do a -10 trim at the drop of a hat, and back again if it needs to!

Given this, it should just "fix itself" in short order rather than have bad trims lying around. Possibly you always see the bad trims because you have just decelerated and hopped off the bike?

[kaldek]

Folks, I have just proven that when autotune is disabled, the trim tables are also disabled and ignored. So, if you have values in your trim table already and disable the autotune, the PCV immediately goes back to base map.

Here's the vid!

[Guest GPM]

I don't want to sound like I'm shooting you down in flames, but I just don't know if the vacuum-controlled switch is worth it. The Autotune trims FAST. And I mean REALLY fast - my tests with the bike running on the centrestand have shown it will do a -10 trim at the drop of a hat, and back again if it needs to!

Given this, it should just "fix itself" in short order rather than have bad trims lying around. Possibly you always see the bad trims because you have just decelerated and hopped off the bike?

I agree its fast, but as has been pointed out a couple of times, everything is post mortem, and not necessarily spot on accurate (I'll try to explain this a little more shortly). I also agree that the worst decel effects happen because you haven't gotten back to that cell yet on accel. or cruise (actually, that is the entire problem! And should you accept that trim before you get back to that cell.... well...). When you are dealing with a 250RPM resolution with map-by-gear enabled, well, that's a lot of cells, and when I am commuting I make a lot of small throttle adjustments (the nature of being stuck in heavy traffic) which is why I think my 2% and 5% throttle positions tend to be so erratic, while higher throttle positions (which are used more in highway and twisty riding) tends to have a nice smooth line. Basically, your autotune will fix up polluted cells eventually, it's the strength of the system, but I think it is better if it doesn't have to - those polluted cells are making the Autotune redo its good work!

Now the accuracy point - as I said, Autotune is post mortem, while the PCV acts on pre-mortem fuelling, so in a basic nutshell the autotune is adjusting the current fuelling based on the results on the previous fuelling - of course, this is all happening in the space of a small fraction of a second, very, very fast, but a lot can change in the fraction of a second.

The system has another point of inaccuracy - it doesn't know how much fuel or air is being used to make that AFR - it only knows the final ratio. This means the system needs to take a 'guess' at what the fuel trim should be based on the previous AFR reading. Now, the advantage of a wideband sensor (over a narrowband one) is it knows just how different the last AFR reading was to the target AFR, so when it guesses how much adjust is needed it will be more accurate than a narrowband sensor would be, but it will still be off the mark in most cases. Thus it will take several cycles for the target AFR to be met again - the system is still very quick at doing this, but those fractions of a second start adding up.

A third point of inaccuracy is the ever changing environment - you start to close the throttle, throttle bodies start to close, this causes air starvation, which has the dual effect of creating vacuum and enriching the AFR (by reducing air content rather then raising fuel). Autotune sees a rich AFR, but doesn't know this is caused by throttle closure, so it lessens the amount of fuel being delivered - this isn't a problem, the system is doing what it is meant to, and what we want to do - maintain that optimal AFR! The problem is that vacuum - the vacuum wants to draw in air (it's what a drop in air pressure does!), the PCV, taking the previous cycles AFR applies a new, leaner trim, but at the same time the vacuum has dropped (though likely not completely, but still enough) which means that air has been drawn in - we get a multiplied effect, double enleanment really, in the combustion chamber both the amount of fuel is reduced and the amount of air has increased. Autotune will see this post mortem, and again the PCV will adjust accordingly (just as it is meant to), but it will result in a little dance as the manifold vacuum returns to the cruise level - the problem is if you leave the cell (which is very likely as when you decel your RPMs drop) you could end up with a trim reading which is way too lean or rich due to the that AFR dance, which means next time you hit it on the way up or in cruise the system has to start guessing again to get back to the right AFR. Another way of putting it is every time you leave a cell in the middle of the AFR dance it undoes all the good work the autotune has already performed by polluting the trim value for that cell!

Its the same problem is you continue to roll off the throttle - as the throttle bodies continue to close, the vacuum rises, which is a sign of air starvation, which the system takes to mean rich running, which it attempts to correct, and so on.

This is all pretty easy to see for your self - I have many times put my bike on the centrestand so I can play with my new toys. Rev it up and pin it with the throttlelock so the RPMs and throttle position stay steady and I can observe the AFR readings jump about before settling down. Close the throttle and the readings go nuts again. Now considering on the road no one has a 100% steady throttle hand (there is always small adjustments from natural body shake, engine vibe and road surface impacting on the suspension). Most of these super small adjustments are not really going to produce a noticeable effect (well, unless you are riding along a goat track of a road), but it is easy to picture the system constantly making adjustments as you go, and those adjustments, while for the large part are 'close enough', will not always be 100% accurate.

Now I would like to emphasise that this is, as you rightly point out, all super fast, which is why 95% of the time it’s not an issue, the system has completely corrected the cell pollution before we even noticed it. For the remaining 5% of the time it will normally be corrected next time we hit that cell - I microsecond of incorrect running, but it is fixed up soon enough. But sometimes the problem will hang around longer, and be a pain in the rear when you get back to it - probably because it stayed there next time you accepted the trims. Hell, you can see it in some of my graphs, spot the places where there is a sudden 20%+ spike in the fuel map! Completely out of place and strangely gone within a reading or two (as the system self corrects).

I can't say conclusively that the vacuum switch will fix the issue entirely - but Coderighter's experiences with it have been positive, and my early indications are that it is working as it should - so I may as well give it a go. And hell, I do like to tinker :blink: (which is probably the main reason I did it, if I were to be truly honest).

[Guest GPM]

I have a video being uploaded to YouTube right now, but it's going to take about 8 hours to get there. I will update this post with the video when done!

Sounds good! Can you provide us with an executive summary as a preview?

[kaldek]

I have a video being uploaded to YouTube right now, but it's going to take about 8 hours to get there. I will update this post with the video when done!

Sounds good! Can you provide us with an executive summary as a preview?

Sure mate! Check for "KaldekBoch" on Youtube in a few hours. OK, so anyway I did the following:

• Cleared out all maps and trims to zero
  
• Sent the zero map to the bike
  
• Started the bike and let it run until the O2 sensor warmed up
  
• Monitored the AFR reading and the "Fuel" value - confirmed it as zero
  
• Set a value of 13.5 in the "0 throttle, 1250rpm" cell and sent the map to the PCV while the engine was running
  
• Activated my autotune by the switch I installed
  
• Watched the powercommander display immediately show negative (minus) fuel values and the AFR hitting the target of 13.5
  
• Clicked on "get table" to get the trim table from the powercommander
  
• Noted that the "0 throttle, 1250rpm" cell had a "-4" value in the trim table stored in the PCV memory
  
• Noted that the live "fuel" value was also -4 and the bike was holding 13.5 AFR at idle
  
• Turned off the Autotune
  
• Noted that the live "fuel" value went back to zero and stayed there, even though there is a -4 value for that throttle and rpm in the trim table
  

There's some fun stuff you can do with the bike on the centrestand - you can set some funky values in adjacent cells, and watch the PCV average the two of them when you move between cells, for one! This averaging reduces the overall accuracy of the Powercommander, and I wonder if in future they will add more cells to allow it to do less averaging. Certainly the addition of the 15% throttle column has surely helped!

[kaldek]

I should add folks, that probably the MAIN reason I've been capturing videos and evidence is because my bike has a mechanical problem at the moment which is causing Autotune to be alternatively good (sort of) and then bad.

My case in point:

• Rode to work yesterday with zero map and Autotune on - felt awesome
  
• Checked trim values - lots of massive negs (-20 or more) in lots of cells, and accepted all the trims into the base map
  
• Rode home with same settings - felt crap
  
• Tested bike on centrestand at cruise throttle, watched Autotune do massive enrichment (opposite to what the base map now said!), hit its enrichment limit and then blow out the AFR to 16:1 and lose revs
  
• Cleared out all trims and base map to zero again
  
• Noted that bike would hold revs and solid AFR at cruise throttle
  
• Rode to work today with no map, autotune disabled, felt great
  
• Rode home, got progressively worse - zero map, no autotune
  

Basically my bike is flip-flopping between running lean and rich - without the powercommander. If I save the trims into the base map when it's running rich, it runs crap when the richness goes away. What's causing it to run rich and then lean? I really don't know yet. I also don't know which of these is normal - is it broken when it's rich, or is it broken when it's lean?

Either way, the bike is going in for a full compression and leak-down test, and spark plug check/replacement over the weekend. I need to work my way slowly through the possible causes, and find the solution before I go anywhere near my custom tune.

Quick edit - I've just been reading the AA1car.com diagnosis web pages (they are BRILLIANT!) and getting a huge list of things to check, including vacuum leaks. A vacuum leak could result in both a bad MAP sensor reading (which could cause my problems) and also over-pressure of the fuel rail by the fuel pressure regulator. These are all very interesting things, because I don't have problems at high revs only low revs/low throttle which is where there would be vacuum present....

Verrrry interesting...

[Guest GPM]

....

Verrrry interesting...

Woah, indeed. Playing around with my bikes vacuum over the last few days has left me pretty certain I have some out of spec valves, but I had already worked that out anyway (fuel efficiency slowing getting worse over the last 6 months and I have picked up a slightly rough idle - it likes to bounce about 200RPM). I am not looking forword to fixing that, but oh well, just time consuming I guess.

But your problems, very strange. Keep us informed.

Some ideas, though, if I may. Easy way to test if you are having MAP sensor issues, unplug it and start your bike - it's pretty obvious when that puppy has failed - but I would check all the vacuum lines under your airbox. Out of interest, what time of day are you commuting at? And more importantly, what is the air temp difference and traffic like? The runs good on the way to work, crap on the way home pattern has a hint of something more then a coincidence to it.

Maybe do a check over of your exhaust as well - the super lean-super rich switch back you are having with the autotune, maybe something is impacting exhaust flow (causing autotune to go nuts in the process)?

Maybe something you pulled apart with your recent maintainance hasn't sealed properly and is causing a vacuum leak? Whats your fuel consumption like? Speaking of vacuum leaks, T-join into the vacuum line heading to the MAP sensor and slap a vacuum gauge on there - what are the readings like? That's a quick and easy diagnostic tool that wont cost you anything.

[Popsrcr]

Ok, factory map, I have target afr and trim table. If I enable by gear for afr and fuel, I lose all afr targets. If I go back to basic, I don't get the targets back, I have to reload the basic map. Uh...???

Yeah it does that for everyone. The trick is to select the table you want, right-click and choose "select all" then "copy" and then when you go to gear advanced you paste that map into each gear's table. You need to do this for both the map and autotune target AFR tables unfortunately! The best way to do it is do one - fuel map or autotune - save the map, then do the other one.

Thanks Mate. I wouldn't have thought you needed to do this. Oh well, got some work to do.

[kaldek]

Autotune video uploaded - see post #111! (One hundred and eleven)

[Popsrcr]

As an FYI, I finally have everything functioning. I got home last night from my work commute and plugged in to look at the trims. I'm surprised that most are plus numbers! I really expected the bike to be running rich already and it would lean out. Sadly, my morning ride was pretty much at idle, but the ride home was a bit more normal. We'll see how this progresses.

Thanks to everyone for the help.

[TX_CLG]

As an FYI, I finally have everything functioning. I got home last night from my work commute and plugged in to look at the trims. I'm surprised that most are plus numbers! I really expected the bike to be running rich already and it would lean out. Sadly, my morning ride was pretty much at idle, but the ride home was a bit more normal. We'll see how this progresses.

Thanks to everyone for the help.

I have been riding with mine now for about 1000 very spirited miles. I see a mixture of - and + trims but haven't really analyzed it in great detail yet. I do have to say that the throttle response is transformed. I don't feel any surging at this point either. Very impressed to date.

[Guest GPM]

As an FYI, I finally have everything functioning. I got home last night from my work commute and plugged in to look at the trims. I'm surprised that most are plus numbers! I really expected the bike to be running rich already and it would lean out. Sadly, my morning ride was pretty much at idle, but the ride home was a bit more normal. We'll see how this progresses.

Thanks to everyone for the help.

So how did you get it to start running good?

[Popsrcr]

As an FYI, I finally have everything functioning. I got home last night from my work commute and plugged in to look at the trims. I'm surprised that most are plus numbers! I really expected the bike to be running rich already and it would lean out. Sadly, my morning ride was pretty much at idle, but the ride home was a bit more normal. We'll see how this progresses.

Thanks to everyone for the help.

So how did you get it to start running good?

First let me conceed that I have little time in on it. Second, it has never actually run bad, the PCV just didn't seem to be working. So, I don't know if it always "worked" and I just couldn't see it, or if it only now has started doing something. The ride home was fine, but hardly a time to get a feel for good or bad. Nothing felt "wrong".

I've got to take it for inspection in a few which will give me some more opportunity to see. I've only accepted my first set of trims.

[kaldek]

But your problems, very strange. Keep us informed.

Some ideas, though, if I may. Easy way to test if you are having MAP sensor issues, unplug it and start your bike - it's pretty obvious when that puppy has failed - but I would check all the vacuum lines under your airbox. Out of interest, what time of day are you commuting at? And more importantly, what is the air temp difference and traffic like? The runs good on the way to work, crap on the way home pattern has a hint of something more then a coincidence to it.

Maybe do a check over of your exhaust as well - the super lean-super rich switch back you are having with the autotune, maybe something is impacting exhaust flow (causing autotune to go nuts in the process)?

Maybe something you pulled apart with your recent maintainance hasn't sealed properly and is causing a vacuum leak? Whats your fuel consumption like? Speaking of vacuum leaks, T-join into the vacuum line heading to the MAP sensor and slap a vacuum gauge on there - what are the readings like? That's a quick and easy diagnostic tool that wont cost you anything.

Just as an update, I have another thread going which describes my problems getting worse. I'm at the point now of investigating my ignition pulse generator wiring and the pulse generator itself. Another member had similar problems to what I'm seeing.

[Popsrcr]

Sorry to hear that. I'll look for the thread.

[Baileyrock]

So what's up with this lately?