Rear Coil Pack et al

Rear cylinder cutting out during warm up and under hard acceleration -once up to temp and normal riding all OK except for occasional misfire - occasionally have rear coil pack fault code so swopped out with old spare and with new pack and new plug but no joy - deftone on here had similar problem due to shorting wiring some while ago and wiring diagram shows that 2 of 3 wires to coil pack share circuit with other components and only white/purple wire unique from pack to ECU but all wiring from pack to splice/connectors seem OK - can't monitor rear pack/other with TuneECU as connection sporadic with engine running - have reloaded map, reset adaption, etc.

Anyone experienced anything similar?

Do you have wiring diagram for that mate?
All the ones I have show the 2 wire SD coils only.
Happy to have a look at it to point you at the right direction.

Ta - can't extract 'cos I only have a password protected copy but it's page 334 of the repair manual here viewtopic.php?f=18&t=16897

Ok had a look.

If you look at the diagram the number 3 connector on the coil packs is the signal from the ecu to fire the pack.
The others 1 and 2 are a positive and a negative, problem here is that they are shared with heaps of other stuff and come to the coils via splices.
Try this: disconnect the coils and pull the light fuse so you can play around for a bit without draining the battery.
Turn on the key and check if there is proper voltage to the 1 an 2 connector of the coils it should be the same as the battery voltage eg 13 volts plus or so.

If you have a low voltage there you need to try to figure out if it is the negative or the positive side that causes the error by swapping the pin of the multi meter to connector negative and a good positive somewhere (acc connector) and then to connector positive and a negative (near the starter motor on the frame or so).
If this is fine and you have ample power to both coil connectors you need to undo the connector to the ecu and clean and lubricate that ( I would do that anyway).

Let me know how you go.

Ta, much appreciated - have, though, already been through the wiring and connectors as you suggest and all seems good.

This morning, however, rear header gasket disintegrated and spat out remnants - so had a bit of a ZatAoMM moment - may not be an electrical problem but a fuelling issue -ie if gasket has been progressively breaking up and leaking for a while, could be that the O2 sensor (which I've been running connected of late) has been over enriching the rear cylinder - at start up, headers are cold and therefore leaking worse than when hot = very rich mixture = fouled plug = misfire - once hot, leakage is less and therefore less rich mixture but still enough to foul plug and misfire occasionally and particularly under hard acceleration - usually get a rear O2 sensor fault code with blown gasket in the past, though - will replace gasket, check O2 readings with TuneECU and see what happens.

Will do - all check out with TuneECU though.

Checked wiring and connectors again - all seemed good.

At start up this morning, rear cylinder cutting out until engine warm - not had anything like as bad as this previously as was effectively warming up on front cylinder only for 5+ minutes - once warm, ran OK apart from occassional misfire - asked Paul R to take a look whilst replacing front wheel bearings and rear header gasket - eventually found rear coil pack connecting pin bent in ECU - sporadic connection a possibility but why bad when engine cold and better when warm?

After Paul waved his magic wand, started up, ticked over and ran fine - all seemed good but after couple of miles, engine dies (not just rear cylinder) at small throttle movement either way - increasingly frequent until happening every 150m or so...........................25 miles of this and got it home (surprised battery lasted so many ignition offs and ons), only one fault code (rear coil pack) - TPS, coil packs, etc all good on Tune ECU.

So.................if the problem was at the ECU connector, how come the problem starts some 4.500 miles after rebuild with new harness and why is problem now not just rear cylinder?

Should say TPS is suspect and about to be replaced. Beginning to think it's time for a new ECU though - anyone have a spare 61041031200?

TPS is possible, the symptoms are however more like lumpy idle and rpm shooting up and down.

ECU mmm, very rare to pack it in.

Just for the heck of it check the negative on the frame near the ecu.

When it dies try to figure out if it is spark or fuel related.
You have spare coil packs just hook one up and crank.
If you have spare injector do the same, connect an air hose to it with a hose clamp and you feel the air coming out when it opens.

Will replace TPS first - if that doesn't work, have spare, but faulty, complete TB - will swop out and see if symptoms remain with that.

So........replaced TPS, no difference, with rear cylinder only cutting in occassionally.

On a whim, decided to change map from OE Akra, which I've been running for a while, back to Jocke's - reset adaption, 15 min reset, no difference with again rear cylinder only cutting in now and then - had a cigarette or two contemplating replacing ECU @ £425 but started up again and ........................ran fine, both cylinders, no missing, etc.

Beginning to think that problem with rear cylinder may not have anything to do with repeated engine cutting out saga (failing side stand bypass switch?) but cannot explain above - road test next.

No road test but bench start - back to running on front cylinder only.........

Anyone in the UK have an '07 onwards ECU I can borrow to check out whether mine needs replacing?

TB swopped out, no difference so now looking for replacement ECU.

Swopped back TB, keeping replacement TPS, swopped over front and rear coils, removed ECU, cleaned out connectors and regreased again, ditto BGC, put it all back together and.......runs perfectly, no missing, no error codes, steady tickover, crisp and fast throttle response - can only think that it was cleaning connectors that made any difference (cf ktmguy)- five or six bench starts and all good so road test next.

Circa 25 mile run up and down village bypass - first third, no issues except couple of slight misfires - middle third, 5-6 complete engine cut-outs, rear cylinder fault code - last third as first - same riding throughout with cut-out more likely on fast open/closed throttle but sometimes at steady throttle, ie almost random.

Anyone know if/how the ECU can be tested? Looks to be a completely sealed unit so assuming that it can't be repaired.

Now have clutch slip under hard acceleration..........

Both cylinders cut out, rear coil pack fault code and will not restart without switching ignition off and on - all, I think, consistent with faulty coil pack, ie engine stalls irrespective of which coil pack faulty.

Has to be ECU?

What they do is hook up the ecu on a test bench that mimics the bike and has all the functions to behave like one.
Could be done on a dyno with test equipment attached to it like tuneecu and a multy meter to test separate bits.

My diagnose is that something is drawing too much current when hot and crashes the ecu (overload protection).
Still don't think it's the ecu.
What part is faulty I don't know neither without looking at the bike.
I suggest to run it hot and then fire the coils, injectors and so on with tuneecu. If you're lucky you might just get the faulty part to fail when you test.
And for starters disconnect the o2 sensors.

Thanks for that.

So went back in to install O2 eliminators as suggested - on way back out, again checked wiring from rear coil pack to ECU and to relays, under fuse box, etc - all OK - decided to check rear coil pack connector wiring and pins again, all seemed OK but......ignition on, engine not running, no fault codes, and fiddled with main loom wiring to connector and, bingo, rear coil pack fault code pops up - repeated this several times and narrowed in on central brown wire and connector - closer look and central 'female' brown wire connector looked very slightly twisted/damaged compared to other two - tried bending tabs, etc but still threw up fault code sooner or later with fiddling - so spliced in spare rear connector from old loom and all seems OK - road test to follow - here's hoping.

Good luck!

All bits crossed - clutch out, waiting for new friction plates to soak up some oil.

Hope you've got it sorted m8. Tracing wiring faults has to be the biggest pain in the arse of owning a bike/car.

15 min reset bench run - couple of falters, no fault codes - feck...............run out tomorrow morning.

Sorted - can't believe whole saga is down to one pin in one connector though.

Not first issue I've had like this and won't be last, no doubt, but good reminder that if you think you've checked all simple things, you probably haven't and should check again.

Thanks to ktmguy, bic and CK.

Sorted - not.............after a few days almost glitch free, same issue has progressively become worse - cutting/stalling out worse between 3-4/5-6 bars on temp gauge and between 4-5k revs - once above both, problem less but still not wholly glitch free - no fault codes though - found broken insulation to secondary flies motor wiring, fixed with liquid insulation but no better - will now replace fitted spare old rear coil connector with new one but don't think that's the problem - looking like it could well be an ECU issue.

'Tis new harness.........well, <10k miles.

Sorted (hopefully)......................not sure how or why but all good after multiple swopping out/over of fuel pumps, TPS and TBs, with latter stripped down, rebuilt without secondary flies, shafts, motors, etc and rebalanced using Harmonizer......................fingers crossed.

Sorted - not..........................right back to square one with stalling every 25m/yds and rear coil pack fault code.

Mate you have to determine what actually happens before you can fix it.

Try to figure out if it is stalling on no fuel or no spark, I posted a short how to a while back.
The fault code at the end of the day means nothing, that is why a lot of dealers struggle with something like that.
The ecu detects no current or a short at the pin to the rear coil, is it the rear coil or is it something else causing this??? No one knows till you run a few proper tests.

As mentioned try to figure out if it is spark or fuel, when you find out what fails try to figure out if you have the correct voltage arriving there and if all related to that is supplying the correct inputs to the ecu.
For fuel and spark to work properly the TPS, temp and cranck sensor needs to work properly.

Long shot but since you done pretty much everything else, is the crank sensor working properly?

Points well made - trouble is, can't pinpoint problem as symptoms are completely variable and usually on road well into journey - can only check wiring, connectors and components on bench and swop out parts to road test - will do obvious first and swop over coil packs 'cos new one ended up in front cylinder and could be that rear old coil pack has coincidentally died.

Keeping thread going is not necessarily much help to others for future reference but at least keeps my post count up.........

I know its a silly question but have you checked the spark plug, I had this happen once and it was loose.

New and checked but will be swopped out again just in case.

Back up and running on two cylinders but not sure how or why..........rechecked continuity between rear coil pack and ECU, voltage at connector, etc - swopped front and rear coil packs, no difference - removed both plugs and checked for spark, all OK after swopping over plugs and coil packs several times, but lack of spark on occasions probably only down to bad plug earth contact, no fault codes - lost track of which coil pack was old, new, front or rear but once got consistent spark over five or six test cycles, put it all back together and ran glitch free during five mile test ride.

Did, however, disconnect ECU and this again suggests that fault may be with ECU - been told of previous similar examples where disconnecting ECU appears to solve component fault code or similar issue but issue returns sooner or later - disconnecting appears to 'clear' ECU of 'imagined' issue but sooner or later ECU 'reimagines' issue - solution was to replace ECU - any thoughts?

it could suggest you have a bad connection in one of the plugs you disconnected-reconnected. Another pin not seated properly, pin wire connection bad or oxidised?
Clue could be the wire to the rear coil pack
The ecu sees that as open circuit and logs the fault, when you did take it apart and refit the issue is gone.

Yep, could be - first problem 'solved' doing exactly that and finding dodgy coil pack connector female - have looked very carefully at both ends again but nothing obvious and both ends packed with dialectic grease. Relatively new loom and coil packs, oldest component in the chain is ECU...........

Will just continue riding and see what happens.

Different part numbers - new ECUs apparently come 'clean' and have to be dealer set up with VIN number, etc on the bike..........have potential access to another '08 SDR ECU and also in contact with guy able to rework s/h ECU, whatever year/model, to '08 SDR spec.

Haven't touched bike since last Wednesday's successful test ride - start up today straight back to non-running rear cylinder with respective coil pack fault code..................rechecked connector pins re voltage, continuity, etc and all good/same as front coil pack, swopped out rear coil pack for new one, disconnected ECU, etc - no difference - spare ECU not immediately available so new ECU on it's way.

Have to grab these parts as soon as they come up.........but you're right, haven't given up quite yet re wiring, etc.

Would a stuck/flooding fuel injector wet the plug enough to stop it sparking and eventually as a result throw up a coil pack fault code?

Sorted with replacement ECU - swopped over couple of times to check and, running on bench only, no rear cylinder or fault code with OE ECU and all good with replacement.

Thanks to Paul R for suggestion and who's thought for some time that there was something dodgy about the OE ECU, Bill at Rubber Side Up for great deal and service and ktmguy for his time and input - have learnt a few things re electrics over the past two months not least of which that wiring diagram, like London tube map, only reflects reality in some and not all ways.

Here's hoping that OE ECU wasn't corrupted by faulty wiring/connector/component and same fate awaits replacement - or is that just paranoia?

First faulty/failed ECU on here?

One remaining glitch - engine will simply stop once during standing warm up to 3-4 bars and then once or twice after closing throttle or at tickover within first half mile or so of riding - after that, no issues - no drop in revs, no apparent loss of electrical power and no fault code - restarts on button without turning ignition off and on - is this the glitch that some have referred to after removing secondary flies, etc?

Yes, all ticked/unticked as required - will swop out fuel pump for a start and then, if no difference, TB for one with secondary flies.

You are probably the ace now of KTM mechanics! How long does it take you to take it apart and reassemble? 6 minutes?!

Rapidly becoming inversely proportional to sexual prowess.

Any progress on this one No.47? I'm having similar dramas, wondering where to start looking.

If you mean the latest glitch, no - have not had time and have been riding with it - think it's faulty fuel pump though.

Fuel pump pressure seems fine and constant - exhaust gas meter shows it very, very rich during startup so have refitted O2 eliminators as advised by Paul R (not sure of logic but 15 min reset was glitch free) - too much local flooding for test ride - probably just needs custom map to suit new set up without secondary flies, etc.