New toy goes BANG :-(
Discussion
Pick up new toy M12 3R. Driving home all ok and great, get onto A1M thought I'd open her up a bit (4th gear) and there was a very loud and I mean loud BANG, pulls over car now running lumpy, lift the rear clip and the plastic intake manifold has cracked in half! Any ideas what could have caused this? Wheres the best place to get an intake manifold from?
It's a bit like Christmas day and my new toy is already broken, Gutted :-(
It's a bit like Christmas day and my new toy is already broken, Gutted :-(

I'm not that familiar with the engine, but does it run with a "wasted spark" ignition system??
(if you look at the wasted spark pairing, the WASTED spark happens on a cylinder between the exhaust and intake stroke, if the ignition is highly retarded (usually on start when ignition angle tends to be a) retarded and b) highly varriable (due to rapid accel of system during first firing events) this wasted spark can occur late enough on the wasted cylinder to ignite the fresh incoming fuel air mixture (again variable with injector duration and timing) and, as the inlet valve is still open at this time, the "explosion" backs into the intake manifold and if there is a plastic manifold, it tends to split open.
It's been a problem on numerous plastic manifolded wasted spark engines from KV6 to duratec etc. (i actually built and ran a rig to constantly stop start a test engine many years ago, with dataloging and high speed video to capture the eventual explosion (iirc it took about 900 odd starts before all the individual parameters aligned to get the backfire)
I wonder if on your car, some issue with the ems caused those parameters to occur whilst it was running normally?? (intermitent crank sensor fault etc??)
(if you look at the wasted spark pairing, the WASTED spark happens on a cylinder between the exhaust and intake stroke, if the ignition is highly retarded (usually on start when ignition angle tends to be a) retarded and b) highly varriable (due to rapid accel of system during first firing events) this wasted spark can occur late enough on the wasted cylinder to ignite the fresh incoming fuel air mixture (again variable with injector duration and timing) and, as the inlet valve is still open at this time, the "explosion" backs into the intake manifold and if there is a plastic manifold, it tends to split open.
It's been a problem on numerous plastic manifolded wasted spark engines from KV6 to duratec etc. (i actually built and ran a rig to constantly stop start a test engine many years ago, with dataloging and high speed video to capture the eventual explosion (iirc it took about 900 odd starts before all the individual parameters aligned to get the backfire)
I wonder if on your car, some issue with the ems caused those parameters to occur whilst it was running normally?? (intermitent crank sensor fault etc??)
Max_Torque said:
I'm not that familiar with the engine, but does it run with a "wasted spark" ignition system??
(if you look at the wasted spark pairing, the WASTED spark happens on a cylinder between the exhaust and intake stroke, if the ignition is highly retarded (usually on start when ignition angle tends to be a) retarded and b) highly varriable (due to rapid accel of system during first firing events) this wasted spark can occur late enough on the wasted cylinder to ignite the fresh incoming fuel air mixture (again variable with injector duration and timing) and, as the inlet valve is still open at this time, the "explosion" backs into the intake manifold and if there is a plastic manifold, it tends to split open.
It's been a problem on numerous plastic manifolded wasted spark engines from KV6 to duratec etc. (i actually built and ran a rig to constantly stop start a test engine many years ago, with dataloging and high speed video to capture the eventual explosion (iirc it took about 900 odd starts before all the individual parameters aligned to get the backfire)
I wonder if on your car, some issue with the ems caused those parameters to occur whilst it was running normally??
(intermitent crank sensor fault etc??)
This is a big learning curve for me, as I've never worked on the duratec before. I can see where you are coming from, as I've had the same problem with a chevy V8 when the timing was wrong. (if you look at the wasted spark pairing, the WASTED spark happens on a cylinder between the exhaust and intake stroke, if the ignition is highly retarded (usually on start when ignition angle tends to be a) retarded and b) highly varriable (due to rapid accel of system during first firing events) this wasted spark can occur late enough on the wasted cylinder to ignite the fresh incoming fuel air mixture (again variable with injector duration and timing) and, as the inlet valve is still open at this time, the "explosion" backs into the intake manifold and if there is a plastic manifold, it tends to split open.
It's been a problem on numerous plastic manifolded wasted spark engines from KV6 to duratec etc. (i actually built and ran a rig to constantly stop start a test engine many years ago, with dataloging and high speed video to capture the eventual explosion (iirc it took about 900 odd starts before all the individual parameters aligned to get the backfire)
I wonder if on your car, some issue with the ems caused those parameters to occur whilst it was running normally??
(intermitent crank sensor fault etc??)
Adrian W said:
Max_Torque said:
I'm not that familiar with the engine, but does it run with a "wasted spark" ignition system??
No Not wasted spark, six individual coils over the plugsI'll take a look at the MBE literaturetomorrow but I don't think it is wasted spark MT.
Mike.
Ok lesson needed for me .....I thought that Wasted spark is basically an ignition pulse taken from the crank sensor regardless of compression or exhaust stroke and fed via ecu etc to the coils so that you get a spark at the plugs every stroke.
As the cams rotate at half the speed of the crank, if the sensor on them was used as well then could the ecu not determine which stroke each cylinder is on and only send a signal to the coils on the compression stroke ?
As the cams rotate at half the speed of the crank, if the sensor on them was used as well then could the ecu not determine which stroke each cylinder is on and only send a signal to the coils on the compression stroke ?
daddysumo said:
Ok lesson needed for me .....I thought that Wasted spark is basically an ignition pulse taken from the crank sensor regardless of compression or exhaust stroke and fed via ecu etc to the coils so that you get a spark at the plugs every stroke.
As the cams rotate at half the speed of the crank, if the sensor on them was used as well then could the ecu not determine which stroke each cylinder is on and only send a signal to the coils on the compression stroke ?
Wasted spark is usually to save cost, if it fires twice every stroke you use half the number of components, as the MBE has six descrete ouput fets and six coils all wired individualy it would be very odd for it to be. In the Noble the cam sensor is only used for starting (i think)As the cams rotate at half the speed of the crank, if the sensor on them was used as well then could the ecu not determine which stroke each cylinder is on and only send a signal to the coils on the compression stroke ?
Wasted spark does fire on each stroke, Imprezas for example run wasted spark, even on the models that have a coil per plug.
The advantage with Turbo cars is seen to be the burning off of fuel not burnt in the power stroke, primarily for emissions purposes. Cam/crank sync is usually used initially at start up and once running can arguably and often is, switched out.
Mike.
The advantage with Turbo cars is seen to be the burning off of fuel not burnt in the power stroke, primarily for emissions purposes. Cam/crank sync is usually used initially at start up and once running can arguably and often is, switched out.
Mike.
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