ECUs - engine brains

Slow things.

Put key in, press start button ASAP, engine splutters into life, coughs
a few times and stops.

Turn ignition off, turn back on, wait a few seconds, hit starter button,
engine cranks a few times and then starts, and then chucks out a load of
oil smoke.

I've had this happen to me on the Porsche, just happened on the ZX10,
and also happened to the Suzuki VStrom, all injection engines, all have
ECUs with in-built immobilisers, all have cats that I bet the ECU is
programmed to protect.

I phoned the garage for help when the Boxster did it as it just wasn't
starting, they said "keep turning it over, it'll sort itself out" and it
did after about 20 seconds, turned on 1 cylinder, then 2nd, 3rd, etc.
Clever little diagnostic routine.

Cause : in all cases I didn't wait for the ECU to do its power on
initialisation before I tried to start the engine. I can understand that
bit, the ECU doesn't get a chance to read any of the sensors, so
probably just tries to start it with the defaults of a normal hot
engine, which obviously doesn't work and it dies. (and then ECU then
goes "oops, I'm going to set diagnostic mode next time I start" which is
why it takes a bit to start next time, ~20 secs+ in the case of the
Porsche)

What I'm guessing about is how the oil gets sucked into the combustion
chamber? ECU thinks somethings wrong because engines mis firing like mad
and exhaust gasses are way out of spec, turns off fuel and ignition
(don't know if they can turn off the hydraulic valves too?), so vaccum
builds up in cylinder and sucks a little bit of oil past the
piston/rings?

Anyway, I must beat my brain into remembering to "Let the bloody rev
needle do its flick up and down fully before hitting starter button, it
does it for a reason!"

 

It beats pressing the tickler button on both carbs until petrol pours
from the overflow
after remembering to remove the bath plugs from the bellmouths before
pressing
the starter button.

 

Do they display Windows Vista logos when you're booting the car?

Unlikely, I'd day.

I'd doubt that. Past the valve guides, possible. But if it sucking via
the rings you might want to let some air into the engine at one point
.

 

'Eiron' wrote...>

Heh, yes its a definite improvement over doing that

Bath plugs in the bellmouths? Is that to stop dirt or insects or mice?

 

'Timo Geusch' wrote...>

If *any* vehicle showed a Microsoft logo that looked a bit XP or Vista
like I'd run for my life!

(I know quite a few use MS Embedded, but one has to hope they've done
the beta testing *before* releasing it, unlike Windows)

Well it was definitely blue/white oil smoke, so its oil, and its being
burned off.

Perfect now, let it cool down, start it (properly), not a trace of
smoke.

Maybe the ECU shuts the secondary throttle butterfly as well as cutting
off the fuel, that will create a nice vaccuum in the chambers?

Haven't a clue really

 

fragmented wrote:

That would be *really* dumb IMHO. The Sprint simply will not turn the
starter motor until it's ready. Why on earth would they let a potential
situation like describe be possible?


--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
116 Giulietta 3.0l Sprint 1.7 145 2.0 Cloverleaf 156 V6 2.5 S2
Triumph Sprint ST 1050: It's blue, see.
www.cuore-sportivo.co.uk

 

Rain, while your café racer is parked outside the café.

 

In the case of some bellmouths, it was to stop dogs and small
children...

 

Also a surprisingly effective primitive anti fuckwit theft device. See
my posting a while back about my old AJS 16C.


--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

ITYM 'broken down in Wales'.

 

'Catman' wrote...>

It *is* really dumb. And really easy to avoid too.

Obviously nearly everyone turns ignition on and then waits a bit and
then thumbs starter. My fault for being quick.

 

Any fool could push my Triton down the road, it had an easy to cut cable
lock at best. Start it? if they could start the fucker they were entitled
to it.

 

In the case of my 31CSR when the K2F magneto was playing up yet again,
positively welcome to it.

--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

'Monkey' wrote...>

It is odd!

Shouldn't be able to, no.

On the 10R it takes about 3 seconds from turning the key to the oil
pressure light starting to flash (turn key, LCD diagnostics, rev couter
flick to max and back, LCD initialises to '0', oil light pressure starts
flashing).

The bloke in the Porsche shop has heard of the ECU getting confused like
this before, but only a couple of other times, its not common.

Hmm, slight flaw in that principal when it comes to bikes

The BMW car and bike, and the Volvo S80, and every other car I've had
have been fine, no problems.

From my experience of these three problems certain manufacturers ignore
this bit, assuming this situation is never going to arise.

If the ECU hasn't had a chance to read the temperature sensors when the
starters pressed, which defaults does it use?

If it guesses the engines hot when its cold, lean mixture, etc, the
engine might splutter and die. Use cold defaults when hot, rich mixture,
etc, and I imagine it'd spit unburned fuel through into the cats,
doesn't that damage them?

 

Don't these usually have electric pre-heaters? Still takes time to
warm up, I guess. Things like air mass flow sensors (if fitted) might
need to warm up as well but those are the only other sensors I can
think of that would have that problem. I suppose there are other items
like throttle actuators etc. that might need to cycle or reset
themselves but these are usually pretty quick.

Everything else, such as pressure sensors, temperature sensors, TPS,
crank & phase pickups just *work*.

One would think it would need, and therefore be fitted with, a more
powerful pump.

 

'Pete Fisher' wrote...>

LMAO.

I'm sometimes glad I missed the early days of biking.

 

That's really important on the 10R. You must wait for all the idiot
lights to sort themselves out and the rev counter to complete it's
sweep back and forth across the dial. If you try and start it before
that you can screw the FI. They told my this when I collected mine.

 

'Ben' wrote...>

Cheers for that.

Bit worrying that it can actually damage the FI.

 

It's not that it can actually damage it, but it can get it's knickers
in a twist and need returning to the dealer for sorting out
apparently.

 

Both my GSXRs were/are the same. The manuals say you must let the
bike finish the startup sequence before pushing the starter.