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Discussion Starter #1
Hey guys-n-gals-

I've been having some issues getting my ST2 back on the road after it sat for a while (was in an accident and didn't have funds to put it back on the road), so I'll cut to the chase and list pertinent details, what's been done and what hasn't worked thus far.

-Sat for ~1yrs, always had gas in the tank. San Diego, CA (not very cold in winter).
-Started up for first 6 months of above period every 2 weeks and warmed up/ran at battery charging RPM for a few-5 mins.

-Rebuild started 2 weeks ago. Charged the old Odyssey PC680 just to turn it over a few times for oil change.
-New plugs (DPR8EA), new fuel pump hoses (factory ones were completely melted), pulled the fuel pump apart and cleaned out all the gunk.
-Now has new battery, fresh gas, checked relays (pump does prime after being pulled apart and de-gunked).
-Have gas in the external line to injectors, plenty of starting RPM (has been on Battery Tender), but it won't light. Even using starting fluid.

Things on my list to check:

-Gunked up injectors
-Fuel pump not pushing enough PSI to set off injectors


Thoughts?
 

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I am sure you changed the fuel filter while you were in there? Have you checked the TPS? Are you getting fire to the plugs? Checked the crank position sensor? Another couple of items could be all electrical connections cleaned, critical components such at temp. sensors and air sensor connections. Bad battery?
Just the first couple of things that come to mind.
 

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Discussion Starter #3
Yes, new fuel filter (Fram). I haven't pulled the plugs while attempting to start yet, but it does fire momentarily when I use starting fluid spray down the airbox and thumb the starter, so I assumed that the plugs were firing. Battery was replaced last week and is brand new/on a tender.

I'll start searching on how to diagnose the various sensors. Thanks for the reminder on cleaning all the connections, I probably should have done that earlier just so it was checked off.
 

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IF it were mine, I'd try a strong dose of Chevron Techron in the gas. Maybe 1/2 bottle to about one gallon of gas. Just turn the key to "on" to circulate the mix. Do it several times. Leave it overnight, and try to start it the next day.

A buddy of mine had good luck doing this on a Corvette engine that sat disconnected from the rest of the car. All but one injector freed themselves up. He took the remaining injector apart, and "pushed" the needle up a bit (freed it up). Then put it back in and it worked also.
 

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I would guess injectors. I had the same type of problems and symptoms. Took the injectors out and had them cleaned, bike started right up on installation. good luck.
 

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Discussion Starter #7
OK, I've got about 1.25gal of fuel in the tank, dumped in a full can of Techron last night and primed it about 20 times. Today it's still just cranking over as before.

Time to start cleaning elect. connections, I think and then try pulling the injectors for cleaning if that doesn't show progress.
 

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The fuel pump, coils and injectors are all powered from the same relay. If the pump primes for a few seconds at ignition on you almost certainly have power to the coils and injectors. However, the ECU depends on getting a signal from the TPS to turn the relay on again after the initial switch on. Also if there is no TPS signal, the coils won't get a ground trigger to spark nor will the injectors fire.
Only other thing. Have you put the hoses in the tank back in correctly, or has one of them came off inside the tank, hence no fuel pressure?
 

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You can narrow down things considerably by pulling the plugs and seeing if they are getting gas. I would pull the air cleaner and watch the intakes. If the gas is good, check the spark. Leave the plugs connected and well grounded and crank it again to see it they are getting a healthy spark. If you have good gas and spark then it's timing.
 

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Discussion Starter #10
Thanks guys for the continued suggestions. I'm back from a short vacation over the holidays so I'll start digging back into the bike and report back.
 

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I'd check for spark at the plugs. If you're using starting fluid and it won't fire off I don't think you've got any spark at all!
 

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Discussion Starter #12
Small update:

Cleaned up the crank sensor (had some random muck on the end), still no fire.
Vert. cyl has spark, and I can see it getting gas, but if I give starting fluid only to the vert cyl, it won't fire.
Horiz. cyl lights it up every time with starting fluid, and definitely has spark, but just dies out. I can't see down the horizontal intake to see if it's getting fuel or not.
If I spray both intakes, it fires largely the same as spraying just the horiz. cyl.

It gives a little hiccup like it's about to fire when I crank it for a few seconds after using starting fluid, but then nothing happens.


Going to check the TPS today.
 

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I had found the invoice and thought of your post, but now I can't find it again. Some drag racing performance shop in Whittier did my injectors for me. Same symptoms as I said before, started right up with the cleaned injectors. They took them apart and did it right.
12220 something address, can't remember the street, it angled into another street[main blvd]
 

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Discussion Starter #14
...started right up with the cleaned injectors...
Thanks Danrduc, it's looking like it's a problem in that area, but I know I'm getting at least *some* fuel into the cylinders, and after letting it crank for a while, wouldn't it build to the point of being able to fire?

This is my first time troubleshooting a bike totally blind like this, so thanks for sticking with the thread. My old GS500E was quite a bit simpler to suss out than this ST.
 

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Discussion Starter #15
OK, did some more checking.

Definitely have spark at both plugs (new), definitely timed correctly. Definitely have fuel in the tank. Definitely have air. Shooting carb cleaner down either throat gets it to light up until the cleaner is gone. Injectors are dribbling out, not a really fine mist as seems to be required.

I'm going to replace the fuel pump and assume it's not getting enough pressure to the injectors to do their work as they've had 2+ weeks with fairly high dose of Techron to bust anything loose. The fuel pump was dead before we pulled it apart and got it spinning up (as noted in OP), but at this point it seems to be weak link and it's been too long since I've seen an ST in person to know exactly what it's supposed to sound like to know if this is healthy or not. Worst case, I've got a spare.

Seem to be a sound conclusion, or do you guys really think it's injectors still at this point?
 

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Discussion Starter #17
I decided to go against the advice offered here. Headed over to CA-Cycleworks, who are about 5mi away, and picked up their branded fuel pump. $150, or so. Not worth dicking around with different connections trying to hack a car one in there IMO, so I coughed it up and I'm glad I did.

Reassembled, poured in a few oz of fuel and primed it by turning the key 4-5 times. Cranked it and it light immediately.

Now to fix the cosmetics! Thanks all for the advice and help!
 

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Mine is the same

My st2 is displaying the same problem.
Mine cut out a hundred miles from home.I was cruising along at about 70mph and there was no coughing ,spluttering, popping, banging. The bike just cut out and refuses to start.
There is no evidence of petrol getting through.
The bike will fire up with a spray of easystart but only for a second or so.
It would indicate a lack of fuel.

Did you manage to sort yours out. If so what was it.
Regards Pete
 

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Pete-- His problem was the fuel pump. In your case of the bike suddenly cutting out, i'd examine the fuel lines in the tank. They crack/burst with age and the fuel is no longer pressurized. Replace the fuel filter while the pump/etc is out.
 

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I decided to go against the advice offered here. Headed over to CA-Cycleworks, who are about 5mi away, and picked up their branded fuel pump. $150, or so. Not worth dicking around with different connections trying to hack a car one in there IMO, so I coughed it up and I'm glad I did.

Reassembled, poured in a few oz of fuel and primed it by turning the key 4-5 times. Cranked it and it light immediately.

Now to fix the cosmetics! Thanks all for the advice and help!
Thanks for following up with your fix, so many times we bench fix problems and once the op fixes it we never here about it. Thanks for posting!
 
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