Trouble starting the engine

[Gaanja]

We use the Motec M800 on a Honda CBR 600 f4i engine. The stock CAM trigger has 3 teeth. But two of them are ground off as Motec requires only one. The wiring was done as per the drawing given by the motec itself. The ECU always throws up a diagnostic error saying the REF/SYNC is not synchronised. Whenever i try starting the engine, the injectors spray but the spark plugs do not spark. But when I try testing them using the test output option under utilities, the spark plugs spark. I am totally stumped as to what the problem might be.The CAM and Crank trigger sensors used are from the stock. I use the Motec recommended dual channel ignition module (0227 100 200). The following is the initial setup on the motec:

REF SYNC Setup

REF/ Sync Mode: 2 (i.e. multitooth)
Crank Ref teeth : 12
Crank Index Position: 425
REF Sensor Type: 2 (i.e. Magnetic)
REF Sensor edge polarity: 1 (Rise)
Ref trigger voltage : 0
SYNC Sensor type: 2 ( magnetic)
Sync Sensor Edge polarity: 1
Sync Trigger Voltage: 0


Ignition Setup:

IGN type: 1 (Fall trigger)
No of coils:4
Ignition Delay time: 40usec
Ignition current source: 40 mA


If anybody can figure out what the prob is please help me out. If any further info is required plz let me know and il post it

[Gaanja]

We use the Motec M800 on a Honda CBR 600 f4i engine. The stock CAM trigger has 3 teeth. But two of them are ground off as Motec requires only one. The wiring was done as per the drawing given by the motec itself. The ECU always throws up a diagnostic error saying the REF/SYNC is not synchronised. Whenever i try starting the engine, the injectors spray but the spark plugs do not spark. But when I try testing them using the test output option under utilities, the spark plugs spark. I am totally stumped as to what the problem might be.The CAM and Crank trigger sensors used are from the stock. I use the Motec recommended dual channel ignition module (0227 100 200). The following is the initial setup on the motec:

REF SYNC Setup

REF/ Sync Mode: 2 (i.e. multitooth)
Crank Ref teeth : 12
Crank Index Position: 425
REF Sensor Type: 2 (i.e. Magnetic)
REF Sensor edge polarity: 1 (Rise)
Ref trigger voltage : 0
SYNC Sensor type: 2 ( magnetic)
Sync Sensor Edge polarity: 1
Sync Trigger Voltage: 0


Ignition Setup:

IGN type: 1 (Fall trigger)
No of coils:4
Ignition Delay time: 40usec
Ignition current source: 40 mA


If anybody can figure out what the prob is please help me out. If any further info is required plz let me know and il post it

[Grant Mahler]

Have you called MoTeC? They have always picked up the phone when I have called in the past...

[Poe]

Go to the utilities menu and click on ref/sync capture. It's a built-in scope and should help you to verify the wave form and trigger levels. Activate the recorder while cranking the engine. If either the ref or sync has a trigger edge opposite from the setting, reverse the setting and try again. Also make sure that the sync pulse is close to the middle of two ref pulses. You might also want to check the trigger values. If any of the trigger levels are too high or the filter level too high, it would act like no signal. The adjustment is under adjust > sensor setup > ref/sync sensor setup.

How confident are you in your CRIP value? This one parameter is the most important to initially starting the engine. It is the crank angle from the reference tooth immediately following the sync pulse (see why it is important to have the sync in the middle of two ref pulses?) to TDC of the compression stroke of cylinder number 1.

Another thing to check is the firing order of the coils and injectors. I really had to pay attention to the wording in the software when wiring the injectors and coils sequentially. I believe that they both had to be wired in the engine firing sequence, i.e. inj3 went to cyl4 and inj4 to cyl3, etc. It got confusing sometimes when in the test outputs screen - fuel activated by sequence and ignition by cylinder number or something odd like that, but it's been a while.

There will always be a ref/sync not sync'd error with the engine off.

Are you using two dual channel ignition modules, or are you using wasted spark with two coils per channel?

[Discretely elite]

I bet your CRIP is 360 degrees off. Subtract 360 from your value. Your CRIP is the physical angle between the ref tooth and the TDC mark when the engine is set to TDC one #1 cylinder.

I remember the good ol days dealing with this. Definitely check the REF/SYNC capture and post those results.

[Magnarama]

Yeah, if you're running the standard ref sensor and teeth, I think your CRIP is off. From last year's CBR file we ran with 250 deg before TDC. Although not sure how correct this is, as I've never measured it myself. We haven't had issues with it though and our ignition advance seems pretty normal.

But as Poe said, check that the polarities of the sensors are correct, that gave me few minutes of head scratching this year after wiring up our car http://fsae.com/groupee_common/emoticons/icon_smile.gif. Also check that the signals are clear. I remember that last year, the standard sync sensor needed to have a pretty particular gap to get a good signal.

With the sparking issue, I'm not certain, but I'd think that the Motec wouldn't attempt to actually start the engine if the REF/SYNC weren't synchronised to prevent engine damage. They should sync at the rpm you'd see while cranking the engine over.

Also if you keep having problems, give the Motec guys a call. At least in Aus their service is excellent and whenever I've had a problem or question, they're more than happy to chat about it.

[Kirk Feldkamp]

As Poe noted, you mentioned you're using a two channel ignition module, but then you list the number of coils as 4. I'm not sure if that's the settings you need for a wasted spark setup. If you're trying to run sequential ignition, you're going to need one ignition channel per cylinder. Bosch makes a good 4 channel module if you wanted to keep things simple. If you're running an M800, there's not many reasons to NOT run sequential. That is, unless you want a ton of available outputs.

-Kirk

[Gaanja]

I use 2 twin channel ignition modules and not one module with wasted spark method. i will shortly put up the jpeg of the ref sync capture. This initial setup was done earlier by seniors before i took up charge of the daq systems. i redid the wiring part for the new chassis we built. the setup and map on the motec right now was what already existed previously and this setup ran for FSG 2007 and 2008. and i had done quite a few runs with the existing setup. But i changed the engine we were running. We have 2 f4i engines now. And hence i cant quite figure out what the problem is.

The problem is that we had to put the cam trigger from one engine onto the other and i do not know if it was mounted in the right position

I had earlier thought that the cam trigger could be mounted in 4 different ways for a given position of the cam shaft as the bolt holes on the trigger looked symmetrical along the axis of the trigger.I find that there is only one way that the cam trigger can be mounted on the cam shaft.

[Gaanja]

also doesn the CRIP angle also depend on which two of the three teeth we grind off?

[Gaanja]

how do i post pics on this??

[Tom W]

It is almost certainly an error in your CRIP value, otherwise Sync sensor position from the trigger disc. MoTeC are pretty good at explaining how to set your CRIP value, and how to best determine it. If you go to:

http://www.motec.com.au/downloads/downloadseminars/

And download the "Seminar Notes ECU Installation" file you will find a very comprehensive explanation of how to set your CRIP (page 79) and a whole heap of other useful information.

Are you using a hall effect sensor? If not (and possibly even if you are) you are likely to run into problems with your ground off teeth, if the disc is not perfectly round in this area it could quite likely give you false readings, particularly at high rpm, and particularly if you don't have your sensor spacing extremely accurate. Then again once the engine has synced up once it will pretty much run for ever regardless of how many sync errors it is getting.

Anyway with a hundred series ECU you can quite easily just log your sync trace while running to see if you are getting any rubbish, you can also muck about with your arm and trigger voltages if necessary, although that is only a band-aid and not really fixing the fundamental problem.

[Gaanja]

To check if the crip angle is right i went about the procedure given in that particular pdf. I came up with 420 degrees.

As in after the sync tooth just passed the cam sensor head, i counted 14 teeth had passed on the crank sensor for cylinder one to reach tdc on compression stroke again.

But i dunno how my predecessor came up wid 425 degress. It worked earlier so i decided to stick wid it. Also i have made a drawing of which 2 teeth are ground off on the trigger. I am not able to figure out how to paste a pic onto the post

[Tom W]

If you go to http://imageshack.us/ you can easily upload photos/images for everyone to look at.

Do you have a REF/SYNC trace that you can put up?

[Gaanja]

thnx tom

the following is the link to the cam profile drawing wrt to the cam sensor head.

http://img165.imageshack.us/img165/2316/camprofiledrawingqv7.th.jpg (http://img165.imageshack.us/my.php?image=camprofiledrawingqv7.jpg)

[Gaanja]

the original cam trigger when the teeth were not ground off looked like this

http://i53.photobucket.com/alb...ggy7213/HPIM1165.jpg (http://i53.photobucket.com/albums/g41/biggy7213/HPIM1165.jpg)

[Poe]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">The problem is that we had to put the cam trigger from one engine onto the other and i do not know if it was mounted in the right position </div></BLOCKQUOTE>
I think you figured this out, but there is only one way possible for the trigger to bolt to the cam.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">also doesn the CRIP angle also depend on which two of the three teeth we grind off? </div></BLOCKQUOTE>
Yes, this is correct.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">you can also muck about with your arm and trigger voltages if necessary, although that is only a band-aid and not really fixing the fundamental problem. </div></BLOCKQUOTE>
Setting the trigger and filter values is to adjust for varying sensors. Sometimes it can be a band-aid I guess but I wouldn't say that for all cases.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">As in after the sync tooth just passed the cam sensor head, i counted 14 teeth had passed on the crank sensor for cylinder one to reach tdc on compression stroke again. </div></BLOCKQUOTE>
Don't worry about the number of teeth so much as the distance from that first reference tooth directly after the sync tooth passes over the pickup. Then from that falling edge of the ref wheel to actual compression TDC is the CRIP value, not the closest tooth. How is the spacing of the sync pulse in relation to the reference pulses? Do you have the cylinders numbered correctly after re-wiring? Cylinder 1 is on the stator side of the engine, opposite of the timing chain and reference trigger wheel.

[Tom W]

I'm not familiar with the F4i engine, does it use an inductive type or hall effect type sensor on the Sync?

Looking at that second photo you could very well be getting false pulses around the bolt heads, particularly the one near the single tooth.

If the ECU is receiving more sync pulses than it is expecting then it will not spark in order to prevent engine damage.

Anyway a REF/SYNC trace will soon show if thats the problem.

[Tom W]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Poe:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">you can also muck about with your arm and trigger voltages if necessary, although that is only a band-aid and not really fixing the fundamental problem. </div></BLOCKQUOTE>
Setting the trigger and filter values is to adjust for varying sensors. Sometimes it can be a band-aid I guess but I wouldn't say that for all cases.
</div></BLOCKQUOTE>

Judging by how non circular that trigger wheel is I am now more inclined to agree that some careful work with setting arm, peak etc. voltages correctly would be quite important. And of course the best trigger disc design in the world won't make up for voltage settings that are way out of the ballpark.

[Gaanja]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Don't worry about the number of teeth so much as the distance from that first reference tooth directly after the sync tooth passes over the pickup. Then from that falling edge of the ref wheel to actual compression TDC is the CRIP value, not the closest tooth. </div></BLOCKQUOTE>

I don understand this completely.. a drawing or schematic would help. There is something anout this in the pdf that tom put up. But i didn exactly understand it fully. Ppls help me out

[Gaanja]

Hey Poe were you talking about sync relative position (SRP). I quite never figured out how i could measure this

[Poe]

The cam sensor on the F4i is an inductive pickup. We never had any issues using the same setup with 2 ground off teeth. The bolts are out of the sensing range of the inductive pickup and shouldn't cause any problem. The trigger level and filter setting in the Mx00 series is the same as being able to select high and low level mag sensors in the M4 series ECUs.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Hey Poe were you talking about sync relative position (SRP). I quite never figured out how i could measure this </div></BLOCKQUOTE>
The sync relative position can be logged or you can view it in the "view sensors" screen while the engine is running or turning over with the starter. This is what I was talking about earlier with having the sync pulse in between two reference trigger pulses.

Here is Motec's help wording:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">For other trigger systems the Crank Index Position may be calculated by positioning the engine to the REF Index Tooth then recording the number of crank degrees the engine must rotate to reach top dead centre for cylinder number 1 on the compression stroke. </div></BLOCKQUOTE>
The Index tooth is the first tooth on the reference wheel (crankshaft) that passes over the crank pickup after the sync tooth passes over the cam pickup. The crank angle from this index tooth back to TDC compression cyl. 1 is the CRIP value. It does not matter how many reference wheel teeth are in between the index tooth and TDC, the angle is the value you want.

If the sync pulse is too close to the reference pulse (relative position less than 25% or greater than 75%), any wind up or slop in the timing chain can cause the index tooth to change and throw off the CRIP value by the angle between the two reference wheel teeth. Hopefully this doesn't confuse you. (I just read the Motec PDF linked to earlier, and there's a diagram of this on page 57).

Wow, I wish that PDF existed when I was in school...it would have made things a little easier. I had to learn everything by constantly hitting F1 and trying to interpret the help file within the tuning software.

[Gaanja]

hey guys here's the ref sync capture

http://img183.imageshack.us/img183/4163/refsync1nj7.th.jpg (http://img183.imageshack.us/my.php?image=refsync1nj7.jpg)

http://img183.imageshack.us/img183/7169/refsync2xb1.th.jpg (http://img183.imageshack.us/my.php?image=refsync2xb1.jpg)

[Magnarama]

Well, the first thing I see there are that you have offset waveforms, so essentially your signals are oscillating about a voltage other than 0V. From the capture it looks to be around 3.5ish volts for both sync and ref. Not sure why, maybe some form of pullup resistor in the sensor? I don't have a capture of one of our CBR ones, so can't verify if it's correct or not. From what I can tell with the help files, set the Ref and Sync trigger voltages to the voltage that they're oscillating about. Using the capture, find the voltage as well as you can and enter the same for both the ref and sync trigger voltages on the ref sync setup page.

The Ref signal appears to be a rising edge, which you've set up correctly, but the sync is a falling edge. If you take a look at the ECU tuning pdf from the link Tom W posted (awesome find by the way http://fsae.com/groupee_common/emoticons/icon_biggrin.gif ) it shows how to determine the 2.

There also appears to be a fair bit of noise generated in the sync signal. It appears to be coming from the trigger itself. The best fix for this is using the SYNCMag Levels filter. Page 23 and 25 of the tuning pdf details it pretty well.

For working out the CRIP, a good picture of how it's done, showing all the angles is on page 28 of this document https://www.yousendit.com/tran...1HYnUzQVNVbThLSkE9PQ (https://www.yousendit.com/transfer.php?action=download&ufid=Q01HYnUzQVNVbThLSkE9PQ). It also has some good images of falling/rising edge waveforms on pages 21 and 22. I have no idea where I got it from but it looks like it was from an 04 presentation that Motec held at one of the comps. It only stays up there for about 7 days, if anyone wants it after that just pm me and I'll send it.

[JamesWolak]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Discretely elite:
I bet your CRIP is 360 degrees off. Subtract 360 from your value. Your CRIP is the physical angle between the ref tooth and the TDC mark when the engine is set to TDC one #1 cylinder.

I remember the good ol days dealing with this. Definitely check the REF/SYNC capture and post those results. </div></BLOCKQUOTE>

Gaanja. Have you tired this? We run a f4i setup and our crip value is 71 (which is about 360 off from your value).

I would place money on this being your issue.

[Gaanja]

Yes James i tried it. It doesn seem to work. I Think the 2 teeth that you ground off on your CAM sensor are different from the one that i ground off. 65 degrees CRIP seems to be TDC at exhaust stroke and not at compression stroke

[Gaanja]

If you look at the REF waveform the amplitude of the spike varies. So is the ARM voltage set wrt the highest spike or lowest spike?

[Magnarama]

The arm voltage(I assume you mean trigger voltage there) should be the average voltage of the signal waveform. So in this case about 3.5 volts for both of the sensors.

For the filter for the sync voltage, Motec recommend to use 30% of the max voltage. I'm not 100% on this, but I think that you measure your max voltage relative to the trigger voltage. So for this engine speed, the peak sync voltage is about 5/2V or +/-1.5V above the trigger voltage. So the filer voltage is 30% of 1.5 or 0.45V.

Looking at the graph though, some voltages would rise above this level, causing the Motec to 'see' a sync pulse. So just going off the graph I'd choose a voltage of about 1 or so volts.

There's also the problem that at higher speeds the noise could reach the cutoff of 10V. As the Motec cuts the voltage down to 10 for anything over 10, this could cause triggering of the sync pulse. One way to lower the noise could be to wind out the sync sensor so that it's a bit further from the trigger wheel if possible. This will lower all signals from it but should make the signal a lot cleaner. If you take this route, just wind it out a little. Re crank and check signals using the ref-sync capture until the noise is lowered enough.

Have fun with all that http://fsae.com/groupee_common/emoticons/icon_smile.gif.

[Gaanja]

Thanx Tommo... will definitely try it out

[BryanH]

Gaanja, The M800 will not sync up with that sync waveform!
From M800 help file;
"The Mag Sensor Levels table sets the "Arming level" which is the level
that the signal must exceed to be recognised. The actual trigger point
occurs when the signal returns to the voltage set by the "Trigger Voltage"
setup parameter which is normally 0V." Is possible to set "T.V." to 3.8v,but is only trying to cover a major problem.
You should never see anything on the Sync input other than the wave from the single tooth. The weak upside down ref wave in the sync waveform and the 3.8v offset can't happen if the neg wires of both sensors and the shield of both cables are connected to 0 volts (pin B16).
IT IS VITAL that the all the sensor grounds are only connected to B16 B15,
and that there are NO links to the chassis ground which must only be connected to A11 & A12

p.s. The amplitude variation is due to rpm change as each piston slows down approaching TDC compression.
Cheers

[Gaanja]

Hey guys, I just realised, I am running 20 gauge unshielded tefzel wires for both the Crank and Cam angle sensors. Is the lack of sheilding introducing all the errors and noise???

[Gaanja]

Hey thanx guys.... i finally got the engine running.... really appreciate all the help.. http://fsae.com/groupee_common/emoticons/icon_smile.gif..... thank you!!

[Poe]

What did you end up doing to get it running?

[Gaanja]

Well i had to play around with the arm voltages and trigger points... As of now i think this is just a quick fix solution. I guess the problem is that neither of the sensor wires are shielded or even twisted to attenuate noise. Also because of the offset voltage the engine is misfiring a lot at higher rpms. I guess everything will be normal once i replace the existing wires with shielded ones...

[Magnarama]

Congrats mate. It's always great hearing a motor fire up for the first time http://fsae.com/groupee_common/emoticons/icon_smile.gif. I'd definitely recommend that you shield the wires, however most of the noise on the sync signal is not from external sources, but from the the sensor having ferrous metal pass it close enough that it sees a small tooth. Reason I say this is because of the way the pattern repeats itself.

To fix this I'd take the trigger wheel out and make sure there is a minimum amount of material on it that travels close to the sync sensor. If there's still a lot of noise I'd be trying to wind out the sync sensor until all it sees is the single trigger tooth.

You should probably do a ref-sync capture at speed as well. Also, use the logging capabilities of the motec(if you have it unlocked) while doing diagnostics. It picks up things that you wouldn't be able to see otherwise and makes things a whole load easier.

[Gaanja]

It is definitely great to hear the engine roarhttp://fsae.com/groupee_common/emoticons/icon_smile.gif. Actually i wasn physically present when the engine was started. I was on the phone with one of my team mates and telling him what changes to make. It finally ran at one thirty in the morn http://fsae.com/groupee_common/emoticons/icon_smile.gif. I heard it run over the phone... sounded great.

Will definitely do wat you said Tommo . i will also put up the results so that u guys can tell me if anything else can be done to improve it

cheers