My 929 blade engine is igniting fuel in the inlet manifold and blowing open the butterfly on whatever cylinder it happens. An orange flash can be momentarily seen inside the inlet. This happens every 10-20 seconds on idle.

The car is also running mega rich, and dies out on idle unless throttle blipped. Very bad mpg and sticky dark residue on the spark plugs.

Any ideas?

[Edited on 27/7/14 by Rob55]

Firing order incorrect/timing comically out?

my guess is its a car fuel pump on the bike carbs. (tooooo much fuel )

It is a Walbro pump rated to 95psi however the FPR appears to be working correctly and is showing fuel pressure of 47psi.

Should also have mentioned it's fuel injected, not carbs

ECU temp sender open circuit, same for the inlet temp sender, either will make it run mega rich.

Can that be tested with a multimeter?

can't remember the exact figure but my R1 has fuel pressure in the 40's so yours sounds about right.
sounds timing related to me, i would start with the firing order.

A couple of people have also suggested timing, any idea how it could have gone out? It's an AB engine (AB sourced, but not blueprinted), fresh install

Running far too rich will result in all the symptoms you have described, so I wouldn't bother looking at the ignition timing yet. My own bike (Benelli Tornado) has been spitting back through the throttle bodies for a while and when I welded a boss into the exhaust and hooked up a wideband it was running about 10:1 at idle.

Assuming there is nothing daft like a clogged air filter or blocked air intake then the coolant temp sensor is a good place to start. The workshop manual should give appropriate resistances at a couple of temperatures so you can check with a multimeter. The throttle position sensor is also worth a look.

I have had the car tested at 2500rpm it is running 0.9 lambda, 3.6% CO and 410ppm Hydrocarbons

[Edited on 27/7/14 by Rob55]

Quick test on the sensors, with it running unplug them and if it makes no difference you have located the correct area of the fault.

I cannot tell you the values but expect around 100 ohms in boiling water, 4000 ohms in iced water, so just pop into a sauce pan connect a multimeter and heat, if okay the resistance vary with heat.

Not got a power commander have you, if so unplug that first off?

quote:

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Originally posted by Rob55
I have had the car tested at 2500rpm it is running 0.9 lambda, 3.6% CO and 410ppm Hydrocarbons

[Edited on 27/7/14 by Rob55]

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On idle I was getting CO 4.3%, not sure on the other readings. Pretty rich I would imagine

Cheers for the advice Mark Chandler, hopefully help with fault finding

Have you spoken to Andy bates? There's not much he doesn't know about the blade engines

Ok so I spoke to Andy Bates and he suggested that the starter valve may be playing up and causing the injectors to fire in too much fuel. Got the lend of a mates TBs, fuel rail and injectors and fitted that tonight. WOW, what a difference. No more unburnt fuel explosions, no more dieing out, idling smooth. Used a little Gunson Gastester and was getting 0.95% CO. Will take the car back to MOT garage tomorrow to check the fuel emissions on their machine.

Car is booked in to have Power Commander mapped on Weds morning. Hopefully they can adjust the rest within the IVA tolerances