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Hello all, I've been in a bind with this for awhile now. And sorry for a long post, i just want to put everything on the table.. Looked through tons of forums, and either what fixed their issue didn't fix mine, or the answer is just never found. As the title says I have a 2005 600 that I bought to work on. When under load it wouldn't rev past 10krpms, but wasn't too big of a deal to me at the time. Swapped from stock CCT to APE manual CCT, and when i looked at the cams the forward cam (exhaust, closest to headlight?) was a little above the mark, but the rear cam (intake?) Seemed to be 180 degrees from where it needed to be. Followed all the steps to put the cams back in timing, counted to 12 or 13 teeth (whatever the manual said it was, i can't remember exactly right now). Didnt fix it. So I looked at the fuel system, cleaned all the rust out of the tank, fuel pump, replaced the pump filter with new one, and had the injectors cleaned by local shop. Sometime after that, bike wouldn't go past 5-6krpm, would just fall on its face and backfire, but getting to that point was silky smooth. Then the revs would stay at 3,000 rpm on decel or engine brake, and sometimes would go down, sometimes had to shut the bike off. Checked dealer mode, gave me code C25 and C26, so I swapped the plugs with new ones, then moved the coils around, and the codes didn't change, bike still had the same 2 problems. Took it to a shop, they ran a fuel pressure test, said it was 25 psi so they rebuilt the fuel pump (?) And tested, came to 48 psi. Then they recleaned injectors, tank, fuel rail, ordered 4 new coils and tested the connections, said they were in spec and said they even fixed the RPM sticking issue. They did not. Due to moving, cant keep it at the shop to work on. C25 and C26 still shows up, and now won't go past 8k RPMS under load. Did some reading, and unplugged the IAP sensor, bike idles better and just revving it up in N, doesn't stick. Took it for a ride around the block, still doesn't stick. Shortly before I returned, the rpms started staying back at 3k, even though it had done fine so far. At this point I have no idea what else is next. Kickstand switch is good, no clutch bypass, no other modifications besides a yoshi slip on that came with the bike. Is there something else I should be looking at so im not trying to throw parts at it like I feel a shop would? Also, thank you for sticking through to the end.
 

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Well crap. That is sub-optimal. Only thing I have is secondary fuel filter? The high pressure side of the pump. The grease gurus will be along to give real answers shortly.
 

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Discussion Starter #3
Well crap. That is sub-optimal. Only thing I have is secondary fuel filter? The high pressure side of the pump. The grease gurus will be along to give real answers shortly.
Is that something they wouldn't have touch with the rebuild kit? Because honestly I have no idea what the secondary filter is, I might have missed it when I had the pump out the first time
 

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So, don't believe anything a shop tells you. Did dealer mode come before or after you moved the cams around? Being out of sync on the crank and cam sensors can cause ignition codes as well as general running problems. But also if your cams are in time with each other but not the crank, that could be an issue too. Did you check them against that mark, or just each other?

It sounds like you've done everything that rumor and conjecture has told you to do. So, go scientific and actually diagnose. Fuel pressure is good, but what about volume? There's a timed volume delivery test that should be performed as your next step to rule out fuel problems. What you're describing is exactly what fuel starvation causes. And unless the shop charged you about $500 for the fuel pump rebuild, you're original high pressure filter is in there and what causes the volume reduction.
 

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Wait a quick sec. You mean I might have guessed this one right???? I'ma sticky this.
 

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What I don't get is why they would rebuild a fuel pump instead of putting a new one. You can get one for $100 or just use a car fuel pump, which I did & paid less than $75. Its a Denso too, not cheap made stuff.
 

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Discussion Starter #8
So, don't believe anything a shop tells you. Did dealer mode come before or after you moved the cams around? Being out of sync on the crank and cam sensors can cause ignition codes as well as general running problems. But also if your cams are in time with each other but not the crank, that could be an issue too. Did you check them against that mark, or just each other?

It sounds like you've done everything that rumor and conjecture has told you to do. So, go scientific and actually diagnose. Fuel pressure is good, but what about volume? There's a timed volume delivery test that should be performed as your next step to rule out fuel problems. What you're describing is exactly what fuel starvation causes. And unless the shop charged you about $500 for the fuel pump rebuild, you're original high pressure filter is in there and what causes the volume reduction.
I did align the tdc mark on the crank case, then timed the cams from there, never moved engine counter clockwise. I can try the fuel test when I get to my destination, but out of curiosity, how would not enough fuel being sent cause the ignition code? From memory the C24-C27 is when the ckp has signal, but the coil signal is interrupted 8 times or more? Just for learning purposes. Also, thank you!
 

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What I don't get is why they would rebuild a fuel pump instead of putting a new one. You can get one for $100 or just use a car fuel pump, which I did & paid less than $75. Its a Denso too, not cheap made stuff.
They were only looking at the $800 ones, so the one that come with the plate, wires, connections the whole nine yards. I looked and found after market pumps, the gold tube part, but didn't know if i could just swap them out. It looks like the answer is yes 🤡
 

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Checked dealer mode, gave me code C25 and C26, so I swapped the plugs with new ones, then moved the coils around, and the codes didn't change, bike still had the same 2 problems.
So cylinders 2 and 3 are throwing the ignition fault. I'm assuming you swapped coils from a non-fault cylinder (1 and 4) and the faults stayed the same?

Is there spark at #2 and #3? I would assume so but I'll ask the simple question.

Have you checked the system voltage when it's running? 14.0-15.5V?

If all that is good, I'm starting to think the ECM may be failing although I have not read of one with these symptoms.

Any chance you can find a similar good bike and plug your ECM into it to check it?
 

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Discussion Starter #11
So cylinders 2 and 3 are throwing the ignition fault. I'm assuming you swapped coils from a non-fault cylinder (1 and 4) and the faults stayed the same?

Is there spark at #2 and #3? I would assume so but I'll ask the simple question.

Have you checked the system voltage when it's running? 14.0-15.5V?

If all that is good, I'm starting to think the ECM may be failing although I have not read of one with these symptoms.

Any chance you can find a similar good bike and plug your ECM into it to check it?
Yeah swapped coils from one and four, and the shop put 4 new coils in (didnt fix it so they only charged for 2 cause apparently 2 were bad anyways) and there's spark. I haven't checked voltage from battery actually, and not here but if anyone knows of someone in dallas with an 04/05, that would be swell. When I get there I'll be picking up a multimeter to do more electrical testing myself.
 

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The reason I mentioned the battery voltage was that there have been some weird problems and funny fault codes over the years and sometimes a new battery or charging system repair fixed it. Computers don't like low voltage.
 
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I did align the tdc mark on the crank case, then timed the cams from there, never moved engine counter clockwise. I can try the fuel test when I get to my destination, but out of curiosity, how would not enough fuel being sent cause the ignition code? From memory the C24-C27 is when the ckp has signal, but the coil signal is interrupted 8 times or more? Just for learning purposes. Also, thank you!
I was asking because the timeline of your first post isn't really clear. You had a problem, then did a bunch of work, then found the ignition codes. That begs the question if you had the codes from the beginning, or if they were caused by the work being done to address the first problem.

There are error codes for both the CMP and the CKP sensors. We've seen problems that were caused by these sensors (mainly CKP), but the self diagnostic system never registered them. You need some pretty good equipment to really diagnose them, and it's unfortunate that for most of us the only way to rule them out is to replace them. The cost of doing so sucks.
 

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Discussion Starter #14
I was asking because the timeline of your first post isn't really clear. You had a problem, then did a bunch of work, then found the ignition codes. That begs the question if you had the codes from the beginning, or if they were caused by the work being done to address the first problem.

There are error codes for both the CMP and the CKP sensors. We've seen problems that were caused by these sensors (mainly CKP), but the self diagnostic system never registered them. You need some pretty good equipment to really diagnose them, and it's unfortunate that for most of us the only way to rule them out is to replace them. The cost of doing so sucks.
Its difficult for me to remember when I first saw the codes, I THINK it mightve been after cleaning rust from the fuel system, after thinking on it, but again I cant be 100% sure. And I've seen stuff on the CKP sensor not giving a code but causing faults elsewhere, but im not trying to dive into that one unless its a pretty high chance that thats the issue
 

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I had an issue with my RPMs being limited also couldnt pass 6k would just bogg out and choke it felt like.The cause of my issue was faulty generator or rectifier i cant tell u which because at the same time i was getting a weird noise from my stator cover so i swapped out generator and rectifier and my issue went away if this does turn out to be the culprit go oem aftermarket shit i used burned up the wiring within a month not even 1500 miles on em ended going oem just swapped out last week hoping my electric issues are done for best of luck to u man i know the feeling of your bike not running properly shit sucks
 

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I had an issue with my RPMs being limited also couldnt pass 6k would just bogg out and choke it felt like.The cause of my issue was faulty generator or rectifier i cant tell u which because at the same time i was getting a weird noise from my stator cover so i swapped out generator and rectifier and my issue went away if this does turn out to be the culprit go oem aftermarket shit i used burned up the wiring within a month not even 1500 miles on em ended going oem just swapped out last week hoping my electric issues are done for best of luck to u man i know the feeling of your bike not running properly shit sucks
Is that something that could be evident from a battery test? I could also Google how to test those parts, but hey, horse's mouth and everything
 

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If you don't have a service manual, buy one. It seems expensive until you compare it to some of the other tools you need to work on the bike and realize it's the only tool you need for every single job.
 

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All you need is a voltmeter.

Ignition off you should have 12.8v +
Ignition on it should only drop a few tenths of a volt.
Running the starter, it should stay above 10.5 volts
At 5k rpm you should have 14.0 to 15.5 volts.
 
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Is that something that could be evident from a battery test? I could also Google how to test those parts, but hey, horse's mouth and everything
Yea bro get a voltmeter and while bike is running if u have anything less then 14.v charging system is crapping out and lets say at idle you do have 13v for example rev up to 5k and hold voltage should be anywhere between 14.1-15v anything more or less at 5k rpm is an issue
 
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