On my last drive out last year I knocked out my ignition cut off switch out of its holder while paying for a toll. The engine kept ticking over which
I thought was odd, but set off for home none the less. As soon as I started to move it was obvious that I wasn't going to make it home, so pulled
over to reinsert the switch, but before I came to a complete stop there was the loudest backfire from the exhaust I have ever heard, then the engine
just died and wouldn't start.
After a little bit of testing and head scratching , am I wright in thinking that I have blown the ECU, just wanted your more experienced views before
I purchase another ECU.
Thanks
Brad.
Interesting.
Have you worked out why it didn't stop when you removed the ignition switch?
Have you checked the fuses, my megasquirt has a 1Amp fuse.
Is the fuel pump still running?
Are you getting any sparks?
I wouldn't read too much into the massive backfire. That could easily be due to poor ignition whilst you were paying at the toll which would
result in fuel and air in the exhaust and then
The pump can still be heard running when the ignition is switched on, and no, there is no spark.
Is the engine even trying to turn?
if the engine still ran after the switch was broken off, sounds like you have a battery cut off switch , rather than one of the fia style ones with an ignition cut aswell.
Yes the engine does turn even if the cut off switch is out.
I just presumed it was a hot engine keeping it ticking over.
[Edited on 26/2/11 by roadrunner]
All I can think of at the moment and it's a bit of a wild card but my ZX9 has a slightly similar thing whereby it won't start unless I turn
the ignition on and then unplug the smaller plug on the ECU and then plug it back in. The engine will only then start. Like I said a wild gues but
maybe if your plug came loose too.
quote:
Originally posted by mistergrumpy
All I can think of at the moment and it's a bit of a wild card but my ZX9 has a slightly similar thing whereby it won't start unless I turn the ignition on and then unplug the smaller plug on the ECU and then plug it back in. The engine will only then start. Like I said a wild gues but maybe if your plug came loose too.
quote:
Originally posted by mistergrumpy
All I can think of at the moment and it's a bit of a wild card but my ZX9 has a slightly similar thing whereby it won't start unless I turn the ignition on and then unplug the smaller plug on the ECU and then plug it back in. The engine will only then start. Like I said a wild gues but maybe if your plug came loose too.
the intent of the switch is to cut all power. Basically it should always kill the engine, hot or not. If the engine has no electricity, it should give
no spark, which in turn should kill the engine or not allow it to start.
The fact that pulling the key did not kill the engine, I would start there, sounds like faulty wiring. I would bypass it completely to see if that
works. The next thing would be check the fuses.
Checked all the fuses and the bypass.
You might have frazed your ECU yes. The cut-off switch disconnects the battery which can mean the regulator goes pete tong and the voltage to the ECU goes up. It could just be the regulator. Have you tried disconnecting the alternator and regulator and just running it off the battery?
quote:
Originally posted by BenB
You might have frazed your ECU yes. The cut-off switch disconnects the battery which can mean the regulator goes pete tong and the voltage to the ECU goes up. It could just be the regulator. Have you tried disconnecting the alternator and regulator and just running it off the battery?
There are 3 things i would check first;
Check the wiring to this switch that fell out.
Check what its supposed to "Isolate" - Battery, Engine, or both.
Check how the original handlebar kill switch was removed / disconnected / replaced. The symptoms you describe are synonymous of a handlebar kill
switch activated. I used to hit the kill switch in the tunnels at high RPM to create the backfire you mention.