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Still won't start

J

jrbuete

Joined Jul 2008
10 Posts | 0+
If I were back in Guam I'd be seriously considering rolling this bike off a cliff into the ocean... at least then I could enjoy it (while diving)....

I've tried everything but pulling the injectors... the wire harness pins good, everything seems fine. I squirt fuel in the intakes and it fires fine but no fuel through the injectors.... The fuel pump provides good pressure...

On rare occasion I see the efi (twice) and both times I pulled the diagnostic and get "1"... which isnt listed...

Is there an easy way to pull the injectors without removing the throttle body or making a mess with the fuel???

Ideas?

Thanks again!:confused
 
The "1" you are seeing it the TPS indicator. It should read "0". Nevertheless, I've not heard of this stopping it fire up. Sorry, not a lot of help but does tell you what the "1" is.
 
i'd be looking at the ECU, which doesn't appear to be telling your injectors to fire.
you need to get it on an AXONE and they should be able to check that for you no bother
 
Do you have an aftermarket chip in the ecu. Is the ecu wire cut for the de- restriction process ?

what was the background to the failure. Working one day/not the next or after working on something.

!2v at the injectors ? you should have a constant 12v on one pin of the injectors ignition on. the other side is pulsed by the Ecu.
 
If you don't have 12v humour me and try re joining the de restriction wire if it's cut or cutting it if it's not (should be on an 01).
 
Yep, got the 12 volts when I hit the starter...

I also tried reconnecting the wire but no change...

Next I guess is draining the tank and tearing out the injectors...

Glad this isn't my only bike:)
 
I had a similar sounding problem and checked everything possible and eventually found when i swapped to a different ecu that the eprom was faulty and not sending fuel signal.

Lift the tank, open the airbox lid, look down trhe throttle butterflies and try to start it. You should see the fuel squirting or not which will rule out another thing if nothing else.
 
no fuel is exiting the injectors but when I loosen the fuel line at the throttle body I have plenty of pressure... note to self - don't loosen fuel line and hit start button:)
 
so you got voltage & fuel for sure...so certainly sounds like no output signal if both injectors are not firing...common across both units....Only leaves ECU/Epromm to my way of thinking. Its fallen orf the perch.
 
I reckon you have a fuel hose failure in the tank. You have high and low pressure lines to the Tb's and i think one has popped off or perished.

something else i learnt today which might be a long shot is that If the ecu thinks the throttle is stuck open during diag test at ignition on either by mis adjusting the cable or the Tps being way out then it will cut injector power to prevent an accident. Might be worth setting the Tps.

I still reckon you have a hose off in the tank now though. what you could try is filling the tank right up as sometimes that submerges the loose pipe and it will pick up fuel again. I'm probably gonna get shot down in flames but i really don't think your injectors are blocked.
 
spoonz said:
I reckon you have a fuel hose failure in the tank. You have high and low pressure lines to the Tb's and i think one has popped off or perished.

something else i learnt today which might be a long shot is that If the ecu thinks the throttle is stuck open during diag test at ignition on either by mis adjusting the cable or the Tps being way out then it will cut injector power to prevent an accident. Might be worth setting the Tps.

I still reckon you have a hose off in the tank now though. what you could try is filling the tank right up as sometimes that submerges the loose pipe and it will pick up fuel again. I'm probably gonna get shot down in flames but i really don't think your injectors are blocked.
Click to expand...

Smart thinking..never thought of tank internals.
Hey that info regarding ignition system test and injector power block is an interesting one..had no idea that fail safe was even in the system...how did you find that out Spoonz ol mate...valuable *** bit indeed :thumbup

Definately can't see two injectors blocked either Spoonz.
 
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Can you get your hands on another ECU/ eprom before you rip more apart? your problem sounds exactly the same as mine and this may cure it instantly..
 
I found out about the injector cutout from someone else that had the very same problem as this. He turned the bike over having got a mate to hold the throttle wide open whilst he had a noid light connected to look for injector pulse. his logic being more throttle the more pulsing.

He got nothing at all and promptly went down the road of pulling injectors and ecu chips etc thinking something was fried. clarkie from clarkie Motorsports who tuned and raced apes had found out from aprilia italy about this fail safe and informed us as it had caught him as well.
Long story short pulse was fine and problem was down to low pressure fuel line off in tank. he had fuel pressure in high pressure line so had dismissed delivery issues from the tank. Having asked around this issue seems quite a common one on bikes laid up.

the fuel system is a regulated loop. high pressure in low pressure out.
 
Very interesting mate...thank you for sharing that information, greatly appreciated sir.
Being the loop fuel system...It makes alot of sense indeed. :thumbup
 
pulled the fuel pump, everything in the tank is fine but when I opened it up and saw the wiring I was thinking about Flight 800... a 747 that exploded off the east coast a few years ago due to exposed wiring/spark in a fuel tank... oh well, haven't read anything about aprilias exploding on people:)

Also removed the injectors and they look fine - sprayed some cleaner into em just to be sure.

while hooking up the fuel lines I seem to have buggered up one of the aluminum compression washers a dn of course no one has any... gonna try some brass ones i found...
:dunno
 
bum :pirate

the only thing you have left is to get a noid light or rig something up to look for an injector pulse. only other thing i can see causing an issue to the injectors is the fuel pressure regulator being choked. (never heard of it)

i suspect were missing something obvious here somewhere.
 
Have you pulled plugs on the ECU & clean contacts on plug end with cleaner? (Not ECU)
A spray contact cleaner..let it dry right off before connecting again. Personally i disconnect the (+ battery) before any wiring maintenance. Is there no chance of borrowing another can ( ECU) just to see if fault is still on? This would eliminate the can..and as Spoonz says..then we are missing some simple fundamental here..:dunno

Spoonz..have you any idea of the injector pulse voltage? Is it an IC gate like triac switched or similar..i cannot find anywhere the voltage other than the fixed 12v! Not a great deal left ...scratching head :eatcorn
 
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I would definately be trying to get a used ecu or eprom chip. There is no way to test it other than with a different one. As spoons said testing the pulse would work but getting the gear to do that would be less simple than buying a cheap replacement ecu/ eprom. The ecu switch will only take 10 mins as opposed to hours of fuel pump removal testing replacemnet etc.
 

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