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Discussion Starter #1
After a few sessions on track my 07' exhaust started smoking black or blue especially on up/downshifts and when I pulled off the engine died. Turned over very slowly the first try as though it was flooded, then started normally. After cooling it starts and idles fine without smoke. Next day as soon as I left pits it started bucking like crazy on the gas and wouldn't pull past 4-6k in 3rd, the more throttle the worse it bucked. I had to slip the clutch to control it through the pits. Revving it up quick it misfires or backfires around 3-4k, and holding revs there it sounds like it's missing slightly. When the bike starts to warm up, and holding it anywhere above 3k the rpm will spike and cut back down or bounce back and forth. Also idles at 2k a while before settling down.

Ive tried checking all connections under the air box like the 4 coils.
Spark plugs are black and dry
Checked battery voltage under load
Fuel pump allows a good leak when disconnecting the tank.
Disconnected the TPS, wouldn't start with the IAP disconnected.
Bike has PC3 and QS
I suspect the fuel system, looking for how to test the pump and regulator. Is seafoam worth a shot? It sits in storage with ethanol free gas and stabil but I may not have run it through the system.
 

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First I would disconnect the PC3 and see if it clears up.

Search for fuel volume test, that'll give you a good idea on the pump, but if the exhaust is smoky, then I doubt a lack of fuel is your problem.
 

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Discussion Starter #3 (Edited)
First I would disconnect the PC3 and see if it clears up.

Search for fuel volume test, that'll give you a good idea on the pump, but if the exhaust is smoky, then I doubt a lack of fuel is your problem.
Cheers, just checked the front side spark plug it looks slightly damp and smelled like oil or gas. Totally black. engine has around 4k miles on it.
 

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Discussion Starter #5
Blue smoke is oil, Gray/black smoke is fuel.

If the plugs are black, they're fouled. Get fresh plugs too.
The mechanic there said it was definitely blue smoke, but after the bucking suggested checking regulator/pump. I had a tiny fuel leak on first startup this season from throttle body area that went away, im guessing it was the hose with clamps. Also the oil level went down slightly from half to low mark after a few sessions, id changed it recently so the level could have just settled maybe.
Plug had just a little sheen to it, most likely gas.
 

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Sounds like too much fuel, not too little to me - so I would think the pump is fine.

Are both cylinders showing the same black plugs?

As suggested, disconnect the PC3 or try setting a different map. Sounds to me like the PC3 is malfunctioning or has an incorrect map.
 

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Discussion Starter #8 (Edited)
Same with PC3 disconnected. Pops from the exhaust revving it when rpms are on the way up not after I let off. It doesn't want to rev past 4k. Also passed fuel pump volume test. I don't have a setup to test the fuel pressure regulator, is it as simple as blowing air into the o-ring end and checking it blows off at 43 psi?
 

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Discussion Starter #9
Tested fuel pressure regulator with air an compressor, it starts to allow flow at 43 psi. Looking into cleaning the pump and then im out of ideas other than piston rings not sealing.
 

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Have you checked the TPS and the secondary throttle plates?

Try running it without an air filter to see how it runs (better/worse). You haven't recently oiled the air filter have you (assuming it may be a replacement reusable one)?

I'm just about out of ideas. We may need TeeRiver, Tovar, Recoil Rob, or other resident tech-wizzes to chime in.
 

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Discussion Starter #11
Have you checked the TPS and the secondary throttle plates?

Try running it without an air filter to see how it runs (better/worse). You haven't recently oiled the air filter have you?

I'm just about out of ideas. We may need TeeRiver, Tovar, Recoil Rob, or other resident tech-wizes to chime in.
I tried disconnecting the TPS same result, adjusted it before the last track day.
No idea how the throttle plates should work, I was surprised the other day to find one seems to lag behind the other. I was going to sync them if that's what you mean.
Filter not oiled recently.

Back flowed the pump and the fuel came out looking fine, though the removable filter and pump sump were suprisingly dirty for a 5k mile motor.
 

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Does this bike have the stock gauge? Can you see if there is an FI error?

The plugs have been mentioned, black with sheen. Have they been replaced? Once fouled, cleaning may not be enough.

Had this bike been sitting a while? Maybe an injector is stuck open?

As long as fuel pressure is correct and the ECM is stock, it is hard for the SV to run super rich.

Are you the original owner? Anything happen/done to the bike just before the problem started? With weird problems like this it helps to have as much history as possible.
 

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Discussion Starter #13
Does this bike have the stock gauge? Can you see if there is an FI error?

The plugs have been mentioned, black with sheen. Have they been replaced? Once fouled, cleaning may not be enough.

Had this bike been sitting a while? Maybe an injector is stuck open?

As long as fuel pressure is correct and the ECM is stock, it is hard for the SV to run super rich.

Are you the original owner? Anything happen/done to the bike just before the problem started? With weird problems like this it helps to have as much history as possible.
Stock gauges, I thought FI errors were displayed outside dealer mode? Waiting for delivery of plugs.

Bike ran great out of winter storage and a few sessions on track, dunno if injectors could get stuck after that but it has done less 4 trackdays since last spring due to clutch issues and caliper air leak.

Oil cooler delete and changed the oil out of storage, level was half and went down to low after an hour on track. Also had a temporary fuel leak on first startup, found little pools a top the front cyl and in the V and drops hanging from top of front throttle body. Could have been a fill up spill. Tps adjustment last spring, also bricked the ECU and sent it off for special re-flash, then mapped it myself.
2nd or 3rd owner, may have been a race bike from the beginning. Has been down a few times at least but not for 5 yrs.
 

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So the stock ECM has been re-flashed. The bike also had a PC3? I would suspect something might be up with the re-flash map. Can you flash back to stock?

It also might be possible super rich running from combined ECM flash map and PC3 mapping along with burning oil may have fouled the plugs.

As soon as the new plugs come in, let us know what happens. If replacement makes a big difference that is a good clue. By themselves the plugs should not foul so there is more going on than just that.
 

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Discussion Starter #17 (Edited)
No change with new plugs. The old ones have damp threads and 2-3 of them smell like oil, may have been the 2 rear ones. When I looked at the top of the valves one of the rear ones was wet on top. Coolant reservoir level was at the hose almost, haven't checked the rad yet.

Was gonna sync throttle bodies but seems likely to do more harm than good. Ill upload a video tomorrow but the way ignition cuts is very uniform in terms of rpm and cut time, at least at 3-4k when it starts happening while cold. If I hold a certain rpm it will continue the exact same pattern of cutting out.
 

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No change with new plugs.
If the new plugs made absolutely no difference then fouling is not likely the issue. Replacing fouled plugs should at least let the engine run well until they foul again.

Interesting that the engine is cutting out in a regular fashion. Videos help a lot.
 

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Discussion Starter #20
Since changing plugs and cleaning pump the bike must be running on 1 cyl. Im getting FI, solid red light, cold rear cylinder. The secondary coils fit loose compared to the mains, also gonna re check the rear injector, PO broke connectors and ive been securing it with zip ties..they were solid but nothing else has changed.

No codes in dealer mode.

Radiator took 3 cups of water. I topped it off for the track day before last.

The cutting out is similar even though its on 1 cyl., engine was cold.

 
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