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Discussion Starter #1
I have some problems with my SPS and was wondering trying out one thing, to rule out faulty/dirty fuel injectors.

We all know that the SPS has 4 injectors, of which 2 work from the beginning and the 2 other ones will work at higher RPM.

Now, if I switch the cables on the throttlebodies so that the injectors work in different order, will this effect engine behaviour, because of the positioning of the injectors?

I just want to rule out if any of the injectors are faulty, clogged, dirty or something.

I'm having similar problems as JEC, in another thread.. and I have checked all sorts of things and now want to check the injectors.

Or should I just remove them altogether and have them cleaned?

My problem is that everything works fine at high RPM, open throttle, but at cruising speeds, (40 - 70 mph) at a steady, small throttle opening I'm getting weird throttle response, like there is a dead spot (worn out?) on the TPS? and when engine is hot and I pull up to an intersection or traffic lights, the bike dies without giving it gas and also has a lot of back firing/popping in one exhaust.(but no very loud, just like muted, constant pop-pop-pop...)

TPS voltage is checked ok (idle and zero)
TB sync is checked and is ok, though a bit off
( I just last week took the bike to a track and there it worked great!)
Tank is not dirty, filter *should* be ok (replaced maybe 2 years ago, we don't usually have dirty/bad gasoline. I've always cut open the old fuelfilter and it was never dirty inside)
Fuel pump primes ok, when looking in the tank all seems ok. just before the pump priming stops, there is a squirt in the tank, this is normal? the pressure builds and excess is vented to the tank, right?
Changed spark plugs (NGK iridiums), checked connections, measured the highvoltage side resistance, both had similar ohms.

Battery is ok, charging is ok, R/R is ok, I've struggled with them in the past, but now they are fixed.

wow, this came out longer than I suspected... thanks for reading.
 

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Discussion Starter #4
ok, this is getting frustrating.

I didn't swap the injector cabling, but swapped the injectors themselves on the rear cylinder. no change.


the balance is now set. Fuel pressure has been measured. fuel pump works (i.e. runs all the time while engine running)

What the bike does now is it stalls for no reason at idle after a random time. Like it is starving for fuel. but as I said, fuel is available. This happens now stationary; I've yet to button her up and take a ride, but I feel that it will do the exact same thing when riding and pulling up to an intersection -> closed throttle. At higher RPM / wider throttle openings, everything is fine.

The next thing that will be measured is the actual injector pulses with an oscilloscope.

also, what I did after the last time is I switched the chip inside the ECU, I had a spare one. This chip is for the open Termis. (chip is "073") - no change after the swap.
 

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Discussion Starter #5
$hit, the R/R is cooked. Or at least one of the connectors is fried.

So, there was an easy solution to this. I kick my self for not checking the easy stuff first. I wrongly assumed that all was fine in the battery/charging area.

And, I've said it before and I'll say it again;

the lack of electricity can lead to the most interesting and weirdest symptoms.
 

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$hit, the R/R is cooked. Or at least one of the connectors is fried.

So, there was an easy solution to this. I kick my self for not checking the easy stuff first. I wrongly assumed that all was fine in the battery/charging area.

And, I've said it before and I'll say it again;

the lack of electricity can lead to the most interesting and weirdest symptoms.

Cut the cables, make a bypass operation and solder it together. much better and reliable then stock.

Jocke...........
 
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