SV Portal Forums banner
1 - 8 of 8 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
Hi guys, lurker here

I only ever seem to come here to talk about my problems but I'm having one that I could use some guidance on. Last week, I was out riding the SV and all was well. Rode it to work in the morning and back and later that evening. There was nothing to indicate there was an issue, until I turned around to head home. As you do, I was WOT in 3rd above 5k and noticed some hesitation. I replicated the circumstances to try and see what was going on and it progressively got worse on the trip home to the point where full throttle would only produce misfiring at any rpm. Now my fuel pump has been making nasty noises at me for probably about a year so I've had another on reserve just in case. I of course assumed it was the issue. Upon removing the tank I found a metric S*** ton of rust in the tank and pump housing. I cleaned the tank and filter out thoroughly, installed new fuel pump and pre-filter and reinstalled. Wouldn't you know it once getting it started (which took some effort) it smoked terribly and ran like crap. Pulled plugs and they were soaked in gasoline and looked like they had been running rich for a long time.

Since then I have checked/done the following with no change in running condition:

Compression: 181 front, 172 rear
Fuel pressure: 44 psi with bike off and old pump reinstalled
Spark: good
Filters: Clear as they can be

Any recommendations on what to try next? Would a leak down provide any useful information at this point knowing it has compression? Should I start checking sensors? Light a match and close my eyes?

Let me know what you guys think!
 

·
Obsessed with SV1000s
Joined
·
8,729 Posts
I bought a 2006 SV1000S a couple of years ago that had been sitting for over a decade with half a tank of gas in it and there was quite a bit of rust in the tank. Here's my thread about it. After lots of trouble shooting that included new plugs, the fuel pump from my 2005 crashed SV1000, and sending the fuel injectors off to be cleaned, I found out what was causing my horrible stumbling and misfires at 5,000 RPM and above. I had been using premium ethanol-free gas and decided to use the cheapest 87 octane after finishing off a tank of the expensive 91 octane, ethanol-free stuff. To my surprise, all hints of running issues completely disappeared immediately. If you've been using high octane gas, try the 87 octane and see what happens. Good luck! :niceone:
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #3 ·
That certainly would be a cheap fix, I'll have to see if I can find any ethanol free 87 in the area... worth a shot anyway as the tank is empty now. Thanks!
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #4 ·
Bumping this as I have new information but am still looking for insight on a path forward.

After diagnosing everything easy myself (new gas, spark plugs, compression, fuel pressure, voltage, power commander) I took it to a dealership and had them do a compression and leak down check as well. On a cold engine, front cylinder was 155 psi, rear was 150 psi, leakage for both was 2-3%. To me this would indicate my issue is not mechanical.

That being said, what would cause the bike to run rich to the point of fouling the plugs at idle? There are only a few sensors on the bike that I believe could cause it, TPS, Crank Position, maybe water temp?, and the ecu itself. Has anyone had a similar issue? Is it possible to test sensors with a multimeter for correct values?
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #5 ·
Checked a bunch of stuff out now, starting with the tps. Tps needs adjustment but is in working order. reads 1.2 to 4.2 kohms in a linear fashion. I think I found a problem though, using a multimeter on the power supplied power pin of the tps connector, and negative terminal of the battery yields 1.12V. Acoording to the service manual this should be between 4.5 and 5.5V. I also checked the supplied power pin of the IAP sensor connector, they share the VCC pin on the ecm, and it also reads 1.12V. I have a fully charged battery, so this should imply the ecm has a short?
 

·
Registered
Joined
·
12 Posts
Comparing the SV fuel pump to that on my V-Strom, try a fuel flow test. If the volume of fuel is correct, then check the fuel flow pressure plus the low pressure fuel screen. However if the fuel flow test fails, consider a bypass of the existing high pressure filter. With rust / dirty fuel in the tank, it is most likely the high pressure filter that is the cause. While these threads are for the V-Strom, they will help as a guide. https://www.vstrom.info/Smf/index.php/topic,3981.0.html and http://www.vstrom.info/Smf/index.php/topic,6105.0.html.
 

·
Registered
Joined
·
2,210 Posts
If you have both the inlet screen and high pressure filter clean....then your TPS voltage reading looks like a good place to dig in. If it's supposed to be getting 5V from the ECU ...and it's not...then you have your culprit. The wiring can develop high resistance at plugs or along the wiring route and that's what I'd be looking at. Check the voltage at the pin out of the ECU which will say yay or nay if it's doing what it should, and if you get the 5V then you have a bad connection or bad wire to the TPS.

When the filters clog it normally happens slowly which could have masked the TPS problem which will make it run rich and now that it's getting fuel properly it needs the TPS to modulate it. Shouldn't be too hard to find now that you've narrowed it down.
 

·
Disturbed, very...
2003 SV1000S
Joined
·
1,389 Posts
IF you had a quote "metric s*** ton" of rust, the filter would have been overwhelmed, and your injectors WILL be grubby as hell....

I had the issue with the protective factory coating in my tank doing the same thing, (most bikes had that flushed out before build), and
even though i sorted the filter/pump, she still was not happy.....wet plugs and all.....got the injectors flow tested and they squirted rather
than sprayed.......ultrasonic bath and cleaning fluid and away they went again....woo hoo....

Not saying it is all your probs, definetly chase the electrical things, but, get them squirters spraying

( editorial note......if it was a metric S***, it would be tonne, not ton..... s*** stirrer i am....)
 
1 - 8 of 8 Posts
Top