Engines start and stalls after 2-3 seconds

[seb101]

Hey
Im trying to help out a person with FZ6 2006, he did a rebuild of the bike after high speed overcooked wheely.... He got all the parts replaced, including cable leads, switches and connectors, he also had to replace fuel pump relay and it worked from first go. About a month later he got rest of the missing parts (mechanical parts, nothing electric like brakes, mounts etc.) and it's acting up starts normally, without any problem and stalls after 2-3 seconds, one after another, no problem starting it up.

What's important it doesn't seem to just cut it out, it stalls but he can hear fuel pump working.

Already checked:

Imobiliser - with both black keys, imobiliser light goes out normally when starting

Fuel pump - swapped whole tank with fuel pump from other fz6, doesn't make a difference

No errors in DIAG

ECU reset


Any other ideas?

 

[Motogiro]

Regardless of what's been changed out it sounds likes it's low volume of fuel. It starts each time but then dies. That would seem like there is enough initial fuel pressure to push some fuel in but then as that fuel is used the system can't deliver anymore fuel.

 

[FinalImpact]

A high speed wheelie?? This led to replacement of all this - as in crash? Sorry, not following that.

Our bikes don't come with an immobilizer but I would get a hand held multimeter (DMM) and see what works when its runs and what is off when it stalls. You need to check the injector signals and ignition signals. Either feed it some gas externally through the TB or check for spark as it dies. ONE IS MISSING!

The most probable is the immobilizer turning off the fuel at the injector, but that's just a guess if the fuel pump is in fact working properly...

Because it starts and runs but times out at exactly the same duration of time each time, I would suspect the fuel injectors are turning off. To test this, find a way to probe the Fuel injector(s) just one will do, connecting the test leads to each side of one injector wire. At idle this is a 12V DC pulse and should show up on meter. You could use a 12V lamp also. It will pulse on and off. An option is to unplug an injector, take fine wire strand and insert it into the connector making contact with conductor in the plug and start it. On our bikes the positive lead should be Red with a Blue trace. The Negative being Red w/Black trace #1/#4 and Green with Black trace #2/#3.

If this signal abruptly stops at the same time the bike turns off, I suspect the immobilizer is acting.

You can repeat the same test on the ignition or simply unlpug one of the spark plug caps and insert a spare spark plug. If the grounded sparked plug body quits throwing a spark the ignition is being cut.

Q? Do you have to cycle the key off to make it restart or just engage the starter?

You could also feed the bike some gas with the air box lid off. A couple of drops of gas in at least two (all) of the throttle bodies will let you know the ignition works but it has no fuel.

Lots of info I shared. All just ideas. Ask questions and tell me you didn't steal someones bike! :spank: :BLAA:

Good Luck!

 

[greg]

euro bikes come with immobilisers as standard

 

[seb101]

Thanks for your help. I gave him all your ideas, we'll see what comes out of it.
Nha I didn't steal it, I hope he didn't either The wheely crash was around 100kmh/60mph so it's quite possible he had to replace alot of the parts, not sure how the bike landed after that and if it hit anything else aswell.

Oh and about the key, no he doesn't have to swtich it on/off, hitting the starter fires it up, any ideas?

 

[CavDoc]

Not a bike mechanic, but every time I've had a "run for 2-3 second then shuts down" it's either been a sensor or an immobilizer to blame...especially if it just shuts off (rather than coughing and choking until it dies). Sorry I can't give ya too much more...I learn about things on the FZ as they break or need maintenance, haven't had to deal with any electrical problems yet (knock on wood)

 

[FinalImpact]

Have you checked under the right side pod for the tip over sensor. I'm pretty sure it kills the fuel pump though.