PC3 problems starting on 08 SG
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Cruiser
Joined: Feb 2008
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From: Wisconsin
PC3 problems starting on 08 SG
Have any of you guys had problems starting after the bike is already warm? I am guessing it has something to do with my pc3. Once the bike is hot and I shut it off, it sputters and backfires and after about 3-4 attempts I can get it fired up. Has anyone else had this problem? Or should I just contact fuel moto? I figured I would ask you guys first. Thanks for your help in advance.
Jason
Jason
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Joined: Jan 2008
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From: Illinois
I use a sert and I had that same problem with the stock heads and even after I switched to 103+ heads with compression releases.
At first, my tuner adjusted the start up timing. That seemed to solve the problem, but after several miles of riding and hard starts, it proved not to.
I read something on here that I tried and it worked. It turns out that I don't have enough cranking fuel. I am not sure if it works the same way with a pc111 as a cert, but with a sert, you can test it by hitting the starter as soon as you turn the ignition on. Don't wait for the engine light to go out.
If it fires up easily when you hit the starter as soon as the ignition is turned on and starts hard if you wait for the light to go out, you are not getting enough fuel while cranking.
With the sert, a small amount of fuel is dumped into the motor as soon as the ingnition is turned on. If you wait for the light to go out when the motor is hot, that fuel has already disappated.
You'll get alot of different opinions on here about what the problem is, but after 12,000 miles of trying different things, I found out for certain for me it was not enough cranking fuel.
Dennis
At first, my tuner adjusted the start up timing. That seemed to solve the problem, but after several miles of riding and hard starts, it proved not to.
I read something on here that I tried and it worked. It turns out that I don't have enough cranking fuel. I am not sure if it works the same way with a pc111 as a cert, but with a sert, you can test it by hitting the starter as soon as you turn the ignition on. Don't wait for the engine light to go out.
If it fires up easily when you hit the starter as soon as the ignition is turned on and starts hard if you wait for the light to go out, you are not getting enough fuel while cranking.
With the sert, a small amount of fuel is dumped into the motor as soon as the ingnition is turned on. If you wait for the light to go out when the motor is hot, that fuel has already disappated.
You'll get alot of different opinions on here about what the problem is, but after 12,000 miles of trying different things, I found out for certain for me it was not enough cranking fuel.
Dennis
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Joined: Jan 2008
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From: Pacific Northwest
Rotchkes, you lost me on the start it before the light goes out thing. To my knowledge the light goes out after the fuel pump has cycled up to pressure thereby ensuring fuel for starting. If you start the motor before the pump completes that cycle you don't have complete fuel pressure. Logic dictates that this would indicate a rich condition not lean. If I'm incorrect here please show me the err in my thinking.
Ganzo68 I would take a look at the plugs when it starts hard to verify a rich (wet) or lean (dry) start condition and get ahold of Fuelmoto - those guys are great. Good Luck.
Ganzo68 I would take a look at the plugs when it starts hard to verify a rich (wet) or lean (dry) start condition and get ahold of Fuelmoto - those guys are great. Good Luck.
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Joined: Jan 2008
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From: Illinois
Rotchkes, you lost me on the start it before the light goes out thing. To my knowledge the light goes out after the fuel pump has cycled up to pressure thereby ensuring fuel for starting. If you start the motor before the pump completes that cycle you don't have complete fuel pressure. Logic dictates that this would indicate a rich condition not lean. If I'm incorrect here please show me the err in my thinking.
What makes the difference is that waiting for the fuel light to go out does allow the system to be fully charged, but that has nothing to do with the fuel that has dissappated in the hot motor while waiting for the system to fully charge.
I don't see not waiting on the light to go out to be the permanant solution to the problem. I see it as a good way to test the theory to determine if your bike has too little fuel at cranking. If the theory proves true for you, adjust the cranking fuel table so there is more fuel pulsed into the motor when you turn the ingition on.
This solution is in the sert manual, someone posted it on a thread I started awhile back about 103" hard starting issue.
Dennis
Elite HDF Member
Joined: Jan 2008
Posts: 4,351
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From: Illinois
I also meant to add that when this was being discussed on a different thread, there were several members who sent pm's to me and thanked me for sharing that piece of info. Many of us that have had hard starting problems have been chasing start-up timing, compression releases, heavy duty starters and anything else we could think of to make the problem go away.
It might not be what is causing your particular problems, but it is very easy to test and the cheapest fix if that is your problem.
Dennis
It might not be what is causing your particular problems, but it is very easy to test and the cheapest fix if that is your problem.
Dennis
Tourer
Joined: Apr 2008
Posts: 435
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From: CT.
I am by no means an expert, but I do clearly remember reading on this forum... a couple mos. back, something about tha EFI tuner (pc3) having some kind of software glitche
and was hard to start , the trick was to start bike as soon as the ignition was turned on.
I installed pc3 3 weeks ago, I remembered...and don't wait for the "light"
fires up hot,warm or cold nicely.
and was hard to start , the trick was to start bike as soon as the ignition was turned on.
I installed pc3 3 weeks ago, I remembered...and don't wait for the "light"
fires up hot,warm or cold nicely.
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What rochkes said, well almost...my .02 on this. If you wait for the pump to fully prime the injector dumps a full load of fuel into the cylinder. Rather than the fuel dissapating, I think it vaporizes causing it to easily combust,(hot chamber). Kind of a pre-ignition thing.
Mine actually blew an intake seal during one of the "spit backs".
I may be wrong and probably am but WTH... that's my story and I'm sticking to it...8{) I have been using the starting technique described above for a while now and it works for me.
FWIW - I use normal start up procedures when cold but flip the switch and hit the starter quickly when hot. I do let it idle until all lights are out.
Mine actually blew an intake seal during one of the "spit backs".
I may be wrong and probably am but WTH... that's my story and I'm sticking to it...8{) I have been using the starting technique described above for a while now and it works for me.
FWIW - I use normal start up procedures when cold but flip the switch and hit the starter quickly when hot. I do let it idle until all lights are out.
Last edited by RoadKingRon1; Apr 10, 2009 at 12:41 PM.
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Elite HDF Member
Joined: Jan 2008
Posts: 4,351
Likes: 461
From: Illinois
What rochkes said, well almost...my .02 on this. If you wait for the pump to fully prime the injector dumps a full load of fuel into the cylinder. Rather than the fuel dissapating, I think it vaporizes causing it to easily combust,(hot chamber). Kind of a pre-ignition thing.
Mine actually blew an intake seal during one of the "spit backs".
I may be wrong and probably am but WTH....I have been using the starting technique described above for a while now and it works for me.
FWIW - I use normal start up procedures when cold but flip the switch and hit the starter quickly when hot. I do let it idle until all lights are out.
Mine actually blew an intake seal during one of the "spit backs".
I may be wrong and probably am but WTH....I have been using the starting technique described above for a while now and it works for me.
FWIW - I use normal start up procedures when cold but flip the switch and hit the starter quickly when hot. I do let it idle until all lights are out.
When I find a day of good weather and my tuner has time to adjust my cranking fuel table, we'll find out for sure and I'll post the changes that were made and what the results are.
Either way, hitting the starter on a hot engine sooner instead of later with great results beats adding compression releases and getting no results.
Dennis
Elite HDF Member
Joined: Jan 2008
Posts: 4,351
Likes: 461
From: Illinois
I meant to ask anyone who "knows" for sure......
When you turn the ignition on and go through the start up process, is fuel being pulsed the whole time? Just when you first turn the ignition on? Does it keep pulsing fuel while cranking if it doesn't start?
If I knew that for sure, it would be easier to understand why it helps to hit the starter button as quick as possible on a hot motor.
Dennis
When you turn the ignition on and go through the start up process, is fuel being pulsed the whole time? Just when you first turn the ignition on? Does it keep pulsing fuel while cranking if it doesn't start?
If I knew that for sure, it would be easier to understand why it helps to hit the starter button as quick as possible on a hot motor.
Dennis