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Discussion Starter · #1 ·
Hello Everyone with this problem. I have been through the sh#t trying to figure out stuttering and spitting at about 7,8,9000 rpms. I did everything from fuel pressure flow test, adjusted timing and valve clearances, new plugs, checked coils pulled out and cleaned injectors checked for vacuum leaks changed oil. Replaced iat sensor replaced Iap sensor changed tps and stps to checking wiring all with no codes showing at all. So I was stumpped and could not find answers anywhere. So what I have come up with with trial and error and testing is I believe the problem is stva even though it test fine. I have them separated at the connector and have been testing I had to enable the accelerator function on my PCV and make adjustments to settings and test make more adjustments and retest I am still fine tuning the accelerator pump function but it's just about there. Some people would call it the day or done deal the way its running now but I believe I can get her to run a little better. I ordered the heal tech stva eliminator to cure the fI light and code. Yes it shows a code when disconnected but not while it's connected go figure. But if I get this fine tuning to where I'm satisfied I think I will just eliminate the secondaries permanently. Ebay sellers want $250.00 and up just for the stv actuator. I'm on a fixed income that's alot of cash for me just for that part. I don't know pros and cons to secondaries being deleted but I'm running better than I was. I could not even do a power up wheelie and I run a 08 1000. Buy she will yank the front up once again. This might not fix your problem but if you tried all the standard diagnostics check with no outcome this might be the next thing to check. If any one knows about the proper way to work with the PCV accelerator pump settings it might save me sometime. Not much info on Dyno jet web site. Also could use some input on pros and cons running with out secondaries. Hope this helps someone that is as frustrated as I was. Ride hard but keep y safe.
 

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Someone was just asking about how to check whether the STVA was the issue and Chuckster suggested just unplugging the actuator then manually pushing the throttle plates full open. You will get a fault code and maybe some hesitation on quick throttle down low but it will not affect performance up high.

If it still sputters then you know the STVA is not the issue.

BTW, I don't think the STVA will be the issue. If it does not open, it would still run smooth and fine but like you only had partial throttle.
 
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^This.

Just to double down in that, there's absolutely no reason to disable your secondary throttles, as some people here seem to want to do, except for your situation!

Like @rv6john says, this is precisely the time to disable secondaries and see how that runs.

The secondaries are there to automatically control the manifold vacuum when you crank the throttle open and regulate a smooth transition of air flow so the engine does not lean itself out and stutter. At the engine speeds you are having problems with, the secondaries don't actually do anything*, so cut them out the loop first. For the test, ignore the stuttering at low engine speeds.

*I think they do something if you make very erratic and sudden throttle movements at high speeds by accident or something else, but you get the idea.

If you fix them open and the bike is nice again at high engine speed, then probably they were not opening up properly.

If it makes no difference to those high engine speeds locking them open, it's not that.
 

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Discussion Starter · #4 ·
Thanks for the reply guys. Yeah it helped and ran alot better but still not where it needs to be. After some more research I came across a forum and pretty much same issues. And it was the crank position sensor. So I have one on order. Oh and I pulled the secondary injectors back out and cleaned them again. And left air box off and ran a bore scope zip tied it and had It aimed down 1 of the injectors video recorded it. And rode down the road with rpms up.. They are spraying but not sure if it is enough. But will know more when I get CPK. If that's not it I guess ecu next. Just waiting for last option because a bit pricy and will need to get that one flashed to.
 

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Discussion Starter · #5 ·
Well CPK arrived and installed. But did not make a difference. I have researched and researched I don't know how many hours I have . I have read post after post and have come across many with the same problems to the T but they end with no fix. If I get this figured out I will let the world know. I have repaced just about every sensor except cps, and speed. The thing that really keeps pissing me off is no f#@king codes that sure would help. I'm on a fixed income and this issue is affecting the rest of my life. Unfortunately it's my only transportation so need it running its best not to mention it's not as safe running and riding this way. Am missing something. Is there a way to check the secondary injector signal while parked or do I have to put it on track stands and strap it to the ground which I'm not wanting to do so much. I just can't afford to buy even a used ecu if it does not correct the problem. I hope someone might have some more ideas. If anyone has a 07-08 ecu the are willing to get rid of cheap let me know. Thanks
 

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Discussion Starter · #6 ·
Oh yeah, can anybody tell me if I contacted suzuki if they would work with me or just brush me off and tell me to take it to a dealer. Thanks
 

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Well CPK arrived and installed. But did not make a difference. I have researched and researched I don't know how many hours I have . I have read post after post and have come across many with the same problems to the T but they end with no fix. If I get this figured out I will let the world know. I have repaced just about every sensor except cps, and speed. The thing that really keeps pissing me off is no f#@king codes that sure would help. I'm on a fixed income and this issue is affecting the rest of my life. Unfortunately it's my only transportation so need it running its best not to mention it's not as safe running and riding this way. Am missing something. Is there a way to check the secondary injector signal while parked or do I have to put it on track stands and strap it to the ground which I'm not wanting to do so much. I just can't afford to buy even a used ecu if it does not correct the problem. I hope someone might have some more ideas. If anyone has a 07-08 ecu the are willing to get rid of cheap let me know. Thanks
Have you done a compression test yet? Maybe something a bit more 'mechanical'. Exhaust valves staying open or something?

" Unfortunately it's my only transportation so need it running". I don't want this to sound like an arse, but if it is a 1000 and it's running OK up to 7,000 revs, that'll still keep you ahead of pretty much every fancy car on the road. Is it giving you problems below this engine speed? Try riding with low engine revs, it's got sacks of torque, it'll get you to where you are going.
 

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Discussion Starter · #9 ·
It's flashed with a pcv. And I had it tuned about a year ago or less. I tried to get it dynoed about 2 yrs ago and they could not do it do to the problem I'm having now. I went through the same test and diagnostics and all were good. Plus no codes. Over a period of time and messing with it it cleared up either by itself or something I did but don't know what. So I took it back to get it dynoed. I took it to Attack Performance to yoseph . The are at the top of there game and very recommended. So they set up a custom map. All was great until about 2mnths ago I was hitting the twistys and went to pass a car and lost top end power and the sound of the bike changed. After checking things out I found the spring gave away to the exhaust butterfly valve and closed off. So l completely removed it . Done deal ran fast as hell. Then about a week to 2 later bang my old nightmare problem showed back up. I take exceptional care of my bike. I live in california so it does not sit. It's ridden daily. I have done everything you can think of and what the manual tells you to no success. But during testing I noticed with certain things I try it hit harder a low rpms and sometimes the highs but nothing is consistent. Except for the lows it pulls good. I know its a 1000 and I can get by with the power I have but I'm also very anal and like things right or it will just keep bothering me. I mean I bought a sports bike for the performance so I just want it to perform 100%. Lol.. thanks for the help guys. If you can think of anything else I might of missed please let me know. If there is a so cal. Member near long beach or sorounding areas with a 07- 08 1000 that would not mind letting me try there ecu that would be awesome. Can contact me @ [email protected]. Thanks again guys.
 

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It's flashed with a pcv. And I had it tuned about a year ago or less. I tried to get it dynoed about 2 yrs ago and they could not do it do to the problem I'm having now. I went through the same test and diagnostics and all were good. Plus no codes. Over a period of time and messing with it it cleared up either by itself or something I did but don't know what. So I took it back to get it dynoed. I took it to Attack Performance to yoseph . The are at the top of there game and very recommended. So they set up a custom map. All was great until about 2mnths ago I was hitting the twistys and went to pass a car and lost top end power and the sound of the bike changed. After checking things out I found the spring gave away to the exhaust butterfly valve and closed off. So l completely removed it . Done deal ran fast as hell. Then about a week to 2 later bang my old nightmare problem showed back up. I take exceptional care of my bike. I live in california so it does not sit. It's ridden daily. I have done everything you can think of and what the manual tells you to no success. But during testing I noticed with certain things I try it hit harder a low rpms and sometimes the highs but nothing is consistent. Except for the lows it pulls good. I know its a 1000 and I can get by with the power I have but I'm also very anal and like things right or it will just keep bothering me. I mean I bought a sports bike for the performance so I just want it to perform 100%. Lol.. thanks for the help guys. If you can think of anything else I might of missed please let me know. If there is a so cal. Member near long beach or sorounding areas with a 07- 08 1000 that would not mind letting me try there ecu that would be awesome. Can contact me @ [email protected]. Thanks again guys.
I still feel compression test data is needed. Could there be a valve issue?
 

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Discussion Starter · #12 ·
Yeah, compression check done. Changed all sensors, replaced plugs fuel pressure check 3 times flow test 3 times. Adjust tps and replaced tps and stps. Cleaned fuel injectors twice. Hooked came up to throttle body and rode while recording. I did everything people and the manual said to do with no success. But here is the good news I finally have fixed her. I took out the fuel pump for the fourth time broke it down put the high pressure filter in my ultra sonic cleaner for 4-5 cycles blew through the pressure regulator with compressed air @ 43-45 psi opened right up. Didn't want to blow through high pressure filter because heard they can be fragile. I didn't see much of any thing in my clean tank but figured f#@k it and I ran compressed air through all the orfices of high pressure filter housing. 3 times on the 3rd time it blew out some clear gel crap looked like clear gelatine keep in mind I had no codes, fuel pressure was on point even rode with pressure gauge hooked up to test under load didn't see much drop . Volume test was up to spec. Only used carb cleaner and starter fluid to clean high pressure filter prior. But if you are frustrated like I was when you go to clean your pump strainer and H.P filter. I recommend using compressed air. Hope this helps someone. I am very thorough about repairs but shit happened and could seem to be in spec but it doesn't take much to F things up. Being it was clear could see any obstruction in the filter and it was stuck like a booger. And would only break free with compressed air.
 
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