Perhaps the more experienced can help me set up the My15M which I built as a kit.

With the original IAW15M my 2003/4 Rosso Corsa starts easily and idles well, generally runs OK but a bit fluffy and hiccups around 3000rpm on part throttle.  The bike is standard except for a KN airfilter in an unmodified airbox. It has a standard exhaust system which has the forward balance pipe which all seems to be in good order. TPS set to 150mv with butterflies fully closed, 520mv idle. Throttle bodies balanced with mercury gauges. Idle at 1100rpm. It is a non-catalyser bike.

With the My15M (sport.ecu map) fitted it will only start if engine warm, then very rough and cuts out if throttle opened more than around a quarter. Cannot get a constant repeatable idle that I can use to set mixture etc.  Sounds as if cutting to one cylinder then picking up again at random.  When cold runs for a few seconds with throttle closed with either no or half cold start applied, throttle has no real effect as does not run long enough to pick up. Both exhaust pipes feel warm after several attempts although engine sounds as if only on one cylinder. As battery decays after seven or eight start attempts it kicks back.

1/ Are the following readings normal?

Battery voltage during test. ( Headlamp unplugged )
Multimeter            12.54V
Optimiser            12.4V

TPS output, both butterflies fully closed, LH and RH idle screws wound out.
Multimeter            154Mv  (0.154V)
Optimiser            43

TPS output, as set for good idle with OEM IAW15M, LH idle screw in as required for idle with OEM ecu, RH idle screw wound out.
Multimeter            521Mv   (0.521V)
Optimiser            101

TPS output, full throttle, WOT
Multimeter            4,580Mv   (4.58V)
Optimiser            361

Barometer
Actual          11’c      1020mb   ( Temp with thermometer- bike in garage and cold, air pressure from altimeter and local weather actual from ‘net.)

Optimiser      122%      15’c      15.c      958MB

2/      What TPS breaks should I set?
3/      Is row 0 the TPS output with butterflies closed or at idle position?

First off I sounds like you haven't catered for the actual pressure sensor that your ECU is using. Check the email of the 21st Jan
It says this

1 - The OEM ECU uses 3 different pressure sensors. In your map file you
should change the presssure line with one of the following
MyECU Cfg Pressure=250mV,120mB,4200mV,1060mB
MyECU Cfg Pressure=250mV,120mB,3900mV,1060mB
MyECU Cfg Pressure=250mV,120mB,4750mV,1060mB

If you see 1024mB displayed it is probably invalid. One of the lines
should give you a sensible reading.

The the last section on this page talks a little about starts and your initial setting up - http://www.cajinnovations.com/MyECU/FirstSteps.htm

From your description it sounds like you have not done this yet.

Hi Bob - did you think it would be plain sailing once you built the kit? There is a steep learning curve to embark on now w.r.t. tuning. However do relax, it will come to you. I suspect you are getting too close - stand back a bit. Start playing with the kit and have a look at the ecu maps here on the forum and compare with your map. Pick bits that seem right. Don't be too anal. With the Opti you can bimble about and experiment. If you make a front bottom of it, just reinstate the previous map and restart from there.

No, having got the kit together I realise gliding (plane sailing) is not what we are about.

I will try altering the air sensor setup, I assume I fiddle around until it agrees with the 'actual' reading.  You are right in that I did not do that, part of the fun of this treasure hunt is all the information is in different places - luckily I like cryptic crossword puzzles as well.


I had several years as a helicopter engineer on the oil rigs so the anal bit should be no problem.

I have tried to follow the First Steps but can't get the bike to give a constant output that I can diagnose and adjust.

Perhaps I should think of it as a virtual carburetta and slowly move from weak to rich until it works.

I am now where I wanted to be I suppose, fiddling around and trying to understand the concept of fuel injection - I can quickly refit the IAW15M when I want to ride the bike. 

Off to the Shepton Mallet autojumble tommorow so will do that first thing in the morning.

Any chance of advice on questions 1 and 2 & 3 ?


Edit - tried to add an edit comment to first post about changing question numbers but ran out of characters - like an Ibsen book.  :-/

1 - Apart from the air pressure it all looks good
2&3 - The butterflies closed is not relevant for MyECU.You set the TPS value to the idle TPS value which in your case 100 will be fine. This is row 0

Here's a tip for doing the initial idle adjustments. Any throttle below the TPS base is treated as TPS base. Set the TPS base to something much higher like 150.
This keeps the ECU on row 0 as you either hold on a little throttle to keep it running or adjust the idle stop to keep 1100RPM
Once the idle is sorted set the TPS value to whatever you end up with after all that adjusting.

Is Bobs MyECU figure for WOT ok? My bike is in bits for gearbox overhaul and general tidy up just now so cannot verify this but I have a scrap of paper in my folder with Base 33 = 165mV, Idle 96 = 480mV and WOT of 993 = 4.965V. Cannot remember when or why I wrote these down! :-?

Yeah Gavin, the ADC figure don't follow the analog figure as close as I would expect. I did not notice at first.

  154 mV should theoretically be about 32 on the Optimiser.
  521 mV should be 107
4580 mV should be 938

My figures follow the theoretical ones very close. Bob's are pretty far away, especially at WOT. I would suspect an incorrect resistor value in the divider.

Thanks RAZ, could you advise me where that resistor might be please.  As mentioned elsewhere I did have trouble with the component identification in particular as I was not used to the five bar code.

Bobd wrote on 03/04/12 at 04:20:12:

Thanks RAZ, could you advise me where that resistor might be please.  As mentioned elsewhere I did have trouble with the component identification in particular as I was not used to the five bar code.

I'm not sure your PCB's component id's are the same as the principal schematic (also, values might be changed since this but the relative values should be same):
http://www.cajinnovations.com/MyECU/pics/TPS.gif
It's gotta be one of these.

Maybe you should wait for Cliff's opinion before spending hours on it, I might be wrong.

Sorry I didn't notice the WOT value

If the circuit is assembled correctly the diodes are reversed biased and effectively not there.
The simplified circuit is then a 57K resistor to the cap.

The upshot is there is no current draw and no voltage drop across the resistors. So if you see 4.5V at TPS you should see 4.5V at the on that cap.

I have seen the caps go leaky before. Maybe damaged by too much heat ??

If you do have a voltage drop, try removing the cap and see if it corrects itself

OK, makes sense, almost there,  now what components numbers are those on the MkIV board. The best I can work out is the centre tap B rfrom the TPS is connected to My15M pin 1, then possibly to R27.

All above is wrong, TPS output is on pin 11 which leads to 47K R16 on underside of board, then to 10K R21 and round to the ATMEGA32 chip. 0.1uF C6 is between output of R21 and -ve.

Disconnecting C6 has seen the Optimiser reading go to 903 at 4.6volts, still not exactly right but hopefully better, I will get a new C6 and fit it.

I don't know that of hand but the top of the board has 6 capacitors in two groups of 3. The side away from the edge is the signal.

One and only one should follow the throttle movement.

Reloaded sport.ecu map, adjusted baro to 4300mv, indicates 1016 with true baro of 1020.

Bike started easily from cold, nearly caught me by suprise - so much so I even glanced down to make sure I had the My15M fitted.

Fault seems to have been with C6, temporarily removed.

WOT now reads 921.

Using Ecu Controller 1.32 not sure why there are two TPS displays, a large font and a small font, the large font shows 80, the small font under TPS ttle shows 128.

:D ;D :D ;D :D 8-) :o :) ;) :D :D :D :D

Fab.

You should not be using ECUController 1.32. It is not compatible with your firmware. You were given a link to version 151 or the beta version 160

My mistake,  I am in fact using v1.51.  I had been reading the website and remembered the wrong number.

With regard to the THR and Throttle slider displays.
I understand the TPS output is displayed under the Throttle slider display and is the figure to be edited by wordpad in the *.ecu file, and I read in the Ecu Controller Owners Manual that the THR display is a map index. I am a little unsure about this 'map index', my display is 0.80,   your example shows 2.81. Can you explain this in more detail please and advise when I use these figures.

If you have properly set the TPS base, you should see 0.0 when there is no throttle applied. If you open the throttle to match that of the 2nd row throttle position you will get 1.0

0.8 is just below the 2nd row, so in your case either you have some throttle applied ( or fast idle ) or your TPS base is not correctly set.

You mentioned the Optimiser said 101 before and was advised to set 100. Why is it 128 now?

Not sure why TPS has changed, it seems to wander a bit for instance WOT changes by about 25 to 30 , I sometimes do things with an Optimate Battery charger connected, this is one of those chargers you leave the bike connected to when parked up.  Is it possible the varying battery voltages on/off charge are having an effect? At the moment C6 is removed.

I would expect very little variation. For one the ECU has a 5V regulator which should be immune to such changes and secondly the TPS sits on the same voltage as the chip

OK thanks, I will try refitting the IAW15M and closely monitoring the TPS output, it may be I need a new TPS.

I am so happy the bike starts with the My15M and answers the throttle. I am sure I am very close to a test ride once I have a stable TPS output and have set up the basic idle settings.

If TPS worked previously on original ecu why do you need to change it? The range is broadly correct and you can set up the matrix to reflect the mapping points within. I may be writing crap but getting a new TPS at this stage seems profligate. My TPS signal varies with engine running and not running - well "idle" does. There seems to be about 100mV (ECU ~ 19) difference between what I call idle dead (battery) and idle running (generating). Maybees I have problem?

I'll have to admit that I've never fussed about the TPS reading. I initially saw that it was in the acceptable range and just ignored it ever since. Bike's running well.

Is it possible to worry too much about this?

pete

Mad Farquhar wrote on 03/07/12 at 07:13:08:

My TPS signal varies with engine running and not running - well "idle" does. There seems to be about 100mV (ECU ~ 19) difference between what I call idle dead (battery) and idle running (generating). Maybees I have problem?

No problem. Just set the TPS figure at the running figure. I got a little less variation after doing a (little) overhaul of the butterfly shafts: New seals and replaced that plastic joint with a metal one (from a Volvo P1800  8-) ). The soft bearings for the spindles go oval.

I wonder if the TPS is temperature sensitive, seems rise as I have the engine idling while waiting for it to warm up.

Raz has reassured me about my idle. I remember he described that before somewhere. Think Carl A mentioned throttle seals too somewhere / sometime.
I wont lose any sleep over it as Pete said. Ill PM my phone number  if you want. We can have a chat - maybe next week when I am not working?

Raz - you do have an eclectic choice in vehicles! A P1800  - you petrol head you! ;)

Mad Farquhar wrote on 03/07/12 at 23:34:45:

Raz - you do have an eclectic choice in vehicles! A P1800  - you petrol head you! ;)

Aye, and I am sure this joint will outlast any other part of the entire bike!

Swedish steel - say no more!

The most probable explanation of TPS variation is mechanical. For instance on my Sport Corsa the throttle cable goes to the LH throttle body. There is then a linkage across to the RH throttle body where the TPS sits.
Now add wear and tear, temperature change and the pulsing vacuum on the butterfly valves and you have plenty of reasons why there is a variation between engine running and not.

Yup agreed. Originally like Bob (I think) I put it down to variation in voltage (stopped v. running) but your explanation of MyECU voltage regulation indicates that Razs experience of mech wear & tear in TBs plus the inter-linkages you mention all conspire to give that differential but hey..it doesn't stop the massive grin or the fun in tinkering to get it "going much better". I suppose it depends on the price of the anorak (refer Wiki slang if not familiar) you want to wear :).

Talking of drift:http://youtu.be/Te0V71sGoxA - love the RC car and helo!

So the only 'real' TPS value is with a warm running engine, and I gather not terribly important in practice.  I have been paying too much heed to Cliff's comments in the 'First Steps' where he states the whole tuning process depends on an accurately set idle.

The bike now starts and I am playing with the mixture settings at the moment. I think I may dig out my vacuum gauges to ensure the low range balance is OK.

I am a little uncertain about setting the throttle body airbleed screws, am I right in thinking they allow extra air through an almost closed throttle body to correct the balance or are they affecting the mixture - or both?

Bobd wrote on 03/08/12 at 09:50:02:

I am a little uncertain about setting the throttle body airbleed screws, am I right in thinking they allow extra air through an almost closed throttle body to correct the balance or are they affecting the mixture - or both?

Both. You are balancing the mixture: You affect air without changing fuel. After balancing, both cylinders will have the same AFR.

First you balance using the linkage, at a couple of thousand rpms. The bleeders will have no significance there. After this, you balance at idle using the bleeders. I tend to aim for as little bleeding as possible, closing one side instead of opening the other. If rpm gets too low or high, change the idle cell (ie. do not use bleeders for idle speed).