Running trouble

[Scud]

I probably have one of those sensors, along with a stock TPS (aren't you using an aftermarket one?). Build a wish-list of what you'd like to be able to swap/test and I'll see how much of I have on-hand. I can send it to you - and if none of it helps, you can send it all back.

 

I'm no expert on wiring harnesses, but I do know that the same connectors can be wired differently in different years as manufacturers make changes. This is a general statement for cars and bikes, and I don't know if it is relevant to your situation. I might even have a front wiring harness from a 2002.

[bbolesaz]

Again, newbie thinking out loud -  But would the Guzzi Diag software shed any light on the status of the various sensors?  Fault codes? Or am I expecting too much from early 2000 ECU's.

[czakky]

I do actually have a couple TPS, but I did have a little concern about my timing sensor. I'm going to try a couple things tonight and if I can't get her I'll pm you.

 

Guzzidiag does show fault codes not sure if the 15m (or whatever our ECU is) can throw a code or not but definitely another avenue to check.

[Chuck]

I do actually have a couple TPS, but I did have a little concern about my timing sensor. I'm going to try a couple things tonight and if I can't get her I'll pm you.

 

Guzzidiag does show fault codes not sure if the 15m (or whatever our ECU is) can throw a code or not but definitely another avenue to check.

Yeah, it does.

[czakky]

Aaaargh! I really don't have admit this, but the fuel injector wires were switched. Sadly it made no improvement though...

I'm going to drain fuel and get some fresh-er stuff.

I still haven't re-checked the fuel injectors themselves seeing how I did clean them. Is there anything tricky with putting those back together? (besides not wiring them wrong!)

I'm almost at a loss here....

[Kiwi_Roy]

May we ask how you cleaned them?

Perhaps you need some new ones.

 

I think you checked the polarity on the pump.

 

Try my suggestion of sucking the fuel out of a can to check there's fuel flow, just cause it to prime a few times see if it sucks the level down.

 

Here's how you can make a meter shunt to read the current with a millivolt meter.

[MartyNZ]

...the fuel injector wires were switched. Sadly it made no improvement though...

Have you taken another look at the plugs now?

Black smoke out the exhaust means soot at the plugs. The atomized fuel injected at the wrong time may settle in the intake area, so droplets get into the cylinder instead of mist.

A brush over the plug centre electrodes and a fast run could help clear the soot.

[czakky]

For cleaning the injectors all I did was spray some contact cleaner in the nozzle side, in the back then I attempted to back flush them by energizing them with a battery and spray at the same time. I'm not sure I was successful.

 

I did measure fuel coming back from the regulator, is that the same?

 

Good point about re-fouling the plugs. I only tried to start it twice since I put in new plugs but....

[Kiwi_Roy]

I copied this out of the injector manual, did you manage to find it on line (PM sent)

 

Injectors 

The injectors control the amount of fuel delivered to the engine. The injector is an ON-OFF valve. It has 

just two operating modes, open or closed. 

 

The injector consists of a shell and a pin forming part of the magnetic armature. This pin is pressed up 

against its seat by a spiral spring whose load is determined by an adjustable push ring. The winding is 

housed in the rear part of the casing while the injector nose is at the front (seal seating and pin guide). 

The control impulses from the computer create a magnetic field which attracts the armature and thus 

opens the injector. The amount of fuel injected depends solely on the amount of time the injector is open, 

assuming constant fuel viscosity and density, and constant pressure differential. This time is established 

by the computer depending on the engine’s operating environment. 

 

When the fuel pressure is in the range of 34-40 psi, the jet breaks into a spray as soon as it leaves the 

nozzle and forms an arc of approximately 30°. 

 

Resistance value: 12Ω. 

If you want to test the injector electrically, apply a maximum of 6 volts for an extremely short period of 

time. 

[czakky]

I honestly didn't look yet. That is very interesting info though.

So, uh 12v directly to the injector might've been a little much?

[bbolesaz]

12V won't hurt the injector.  The ECU signal is 12V.

[Kiwi_Roy]

The warning about only using 6 Volts is straight from the Magneti Marelli manual, I don't understand why.

True, the ECU is 12 Volts but only for milliseconds at the time, they may be worried that someone leaves it on for 10 minutes, 12 Watts may burn out such a small coil.

 

 

BTW, I found the Fuel Injector manual again, download it as a pdf while it's available.

 

www.dpguzzi.com/efiman.pdf

[MartyNZ]

Kiwi Roy is right. The same warning about not exceeding 6 volts is in the V11 workshop manual. However, when I tried 6 v, the injector didn't open. 12 volts worked, but I only applied power for 1 second bursts.

Knowing that injectors are normally powered for milliseconds every second revolution, it is clear that they are not rated for continuous power. I haven't burned out any injector yet, using 12 volts for 1-2 seconds, but I don't know how close I am to damaging it.

[Kiwi_Roy]

MartyNZ says you need 12 Volts, that gave me a thought, suppose there is something on your bike limiting the amount of current available to make opening unreliable,

Is fuse 5 in good order / clips tight?, measure the voltage on the red/black wire (relay 5 87) while the pump is running.

It's something simple I'm sure.

Good ground on the ECU?, wire from 23 & 24 to battery negative, that, pulls the injector open by grounding one side.

Anything sound unusual while the pump primes?

Might be time to measure the pressure, the manual I linked shows how.

 

One thing the manual shows incorrectly is a tube on the regulator reference to the manifold DONT DO THAT.

I think that must have been an early idea. The ECU map allows for pressure changes.

 

BTW the injectors put out the same amount of fuel no matter what the manifold pressure , they operate at what's called "choked flow", downstream pressure has no effect. That's how they can calculate fuel consumption on the later bikes, just by injector open time.

[bbolesaz]

Don't understand the 6V thing either.  It's my understanding that while the injector is never continuously opened, still at WOT, the injector is generally set up to be at 80% duty cycle.  I assume that the factory didn't want a ham fisted service tech to apply a 12V ohm meter and leave it there overnight.  Not an issue these days as most ohm meters are way less than 12V, usually the same as the battery in it, either 9V or 3V (2-AA cells).