suddently no firing

[huub]

I didn't use my v11 sport for several weeks and now it won't start. I first thought of the fuelpump or one of the realays, but it turned out that I have no firing. On both sparkplugs! Anyone an idea where to start? He (or is it a she?) just stood in the garage...

[Guest frankdugo]

the first thing is to check the state of the battery

[raz]

I didn't use my v11 sport for several weeks and now it won't start. I first thought of the fuelpump or one of the realays, but it turned out that I have no firing. On both sparkplugs! Anyone an idea where to start? He (or is it a she?) just stood in the garage...

Does the fuel pump prime when you turn the ignition on? If it does, your power feed and ECU is probably OK and the crank position sensor might be next to check. See http://www.centauro-owners.com/phpBB2/viewtopic.php?t=1838 (post #6 by GuzziJack) for how to check it.

[huub]

the first thing is to check the state of the battery

 

Checked the battery, is fine. Startermotor goes round and round.

[huub]

Does the fuel pump prime when you turn the ignition on? If it does, your power feed and ECU is probably OK and the crank position sensor might be next to check. See http://www.centauro-owners.com/phpBB2/viewtopic.php?t=1838 (post #6 by GuzziJack) for how to check it.

 

I'm not sure about the pump, it only clicks. I put a new one on it, just to test, and that one only clicks too. Is that enough, or should it make more noise??

 

Did check and change the relays, but that made no difference (the relays click also of course). And I didn't see or smell the fuel. But if the pump is not working there should still be firing I think when I put the sparkplugs on the cilinder???

 

Your link is very interesting. I will check it tomorrrow.

[raz]

Are you sure the clicking is the pump and not a fuel tap solenoid or something? If it's the pump it sounds like a severe voltage drop somewhere after the relay (assuming relay is ok and battery is good). Like you say if the pump was faulty you would still have spark, BUT the pump, ignition coils and injectors are all powered by the same fuse and the same relay. You should check voltage at the pump or somewhere else downstream the relay contacts. A copy of Carl Allison's schematics will be of good help.

[huub]

Are you sure the clicking is the pump and not a fuel tap solenoid or something? If it's the pump it sounds like a severe voltage drop somewhere after the relay (assuming relay is ok and battery is good). Like you say if the pump was faulty you would still have spark, BUT the pump, ignition coils and injectors are all powered by the same fuse and the same relay. You should check voltage at the pump or somewhere else downstream the relay contacts. A copy of Carl Allison's schematics will be of good help.

 

Indeed, I put the tank off and know for sure now that I have no pump. The clicking was the fuel tap. And I measure no voltage at the pump. So now I'm checking again the fuses, the relays, the wiring, etc, etc. I'll already had the schematics.

[Guest frankdugo]

hub,if there is voltage to the pump---- possibly the diaphram stuck from inactivity--try tapping with power applied

[Guest frankdugo]

excuse huub,see there is no power at pump.previous thread had fuse problems--for what it's worth i have put tie-wraps on &encased in foam the relay holders to reduce vibration

[huub]

Spent some time to check the cables and connections, but didn't see anything that was suspicous. Took the computer off the battry and back again for a reset, but nothing changed. Still no fuelpump and firing.

 

So I'm still looking...

[raz]

Pardon a stupid question but did you check the power fuse? Not the 30A fuse others are having problem with, but the one called F2 in Carl's schematics. That one drives the coils and pump. Don't just look at it, check that you have 12V on both sides of it. It's so easy to miss the easy ones

[dlaing]

Yah, most likely culprit is ECU fuse, Injector fuse, ECU relay, or injector relay.

Another possibilty is the inline diode, but I have never heard of one going bad.

Other possibilities are bad connection along the harnass.

The wiring diagram and some voltage tests are the easies to start with.

Probe each side of every fuse to start, as that is the easiest test.

[fotoguzzi]

no offense but its not the kill switch is it? you are pulling in the clutch when starting? dumb I no but I'm stretching...

[huub]

Yah, most likely culprit is ECU fuse, Injector fuse, ECU relay, or injector relay.

Another possibilty is the inline diode, but I have never heard of one going bad.

Other possibilities are bad connection along the harnass.

The wiring diagram and some voltage tests are the easies to start with.

Probe each side of every fuse to start, as that is the easiest test.

 

Yeah, checked the fuses. Before and after f2 there is 12 volt. There's also 12 volt on no. 30 and no. 87 of the relay. No. 87 is the connection to the pump, the injectors and to the coils.

When use a wire directly from no 87 to the pump, the pump is running but still no firing when I start. There's also 12 volt on no 86 of the relay (to / from the ecu), but not on no 85. That's the connection to the ecu relay and the ecu.

 

What is the ecu exacly doing with the coils, injectors and the pump? How is that relay working?

[raz]

What is the ecu exacly doing with the coils, injectors and the pump? How is that relay working?

That relay is controlled by the ECU and it's powered when engine is running, or cranking. Plus the two second priming at ignition-on.

 

The fuel pump will always run when the relay is powered, since it has a permanent ground. But each coil only have current if the relay is powered AND the ECU wants it to (because the ECU controls each coils' ground path too, separately - not with relays but solid state semiconductors).

 

If you have 12V at the relay contacts (87) but not at the pump, some wire must be broken as you can see on the schematics. You just have to narrow it down. Personally I would disregard the coils for now and concentrate on finding out for sure how/where the wire to the pump is broken. Odds are you will fix all issues when you find it.