Help (I have a hunch its the fuel pump)

[danath 34]

Ugh... So the past week or so, I noticed the bike has been running poorly. Its running rougher, has noticeably less power, and takes significantly longer time to reach redline. Once I hit about 8.5k rpm, I can really feel the power drop off.

So my first thought was that I got water in the tank a couple weekends ago when I washed the bike. I heard what I thought sounded like a gurgling sound as I poured water over the tank rinsing the bike off (no hose at my apartment). I thought this was just the water filling under the little flapper that protects the key hole, and thought nothing of it. It also seemed to run just fine. But just in case, I drained the tank today, filled it with fresh gas, and put in some injector cleaner for good measure. It didnt make a difference.

My next thought was that maybe I accidentally pressed some of the buttons on the face of my PC3 usb, messing up my map. I re-loaded the Brock's map, and it still didnt fix the issue.

So now I am thinking it is my fuel pump. The past month or so it has been whining and making odd noises, but I havent noticed any poor performance until recently. Is there a simple DIY test a newbie wrencher could do at home to see if it is truly the pump, or do I need to take it in? Also anyone know of any good deals on a pump online?

Am I right in thinking its the pump? Are there other things I should look at?

 

[lil charlie]

Sounds like your on the right track.

 

[EarlyBird]

What mods have you done to the busa? How many miles on it? Have you removed the Pc3 and run it stock? Same thing no power? I have had a few Pc3's on another bike go bad on me before.... reason why I ask! What does the spark plugs look like? They should look tan..... if charcoal black.... its too rich or wet and black way to much fuel. Your fuel pump could be going bad as you said. A fuel pressure test of the system could tell you if the pump is at least supplying the proper pressure. Again trying to help!

 

[danath 34]

Almost 14k miles, and its an 08. Ive got a brocks alienhead with the PC and marble mod. Its been running fine for about a month (or more?) so far with these mods. I also recently changed the plugs (same time as the pipe). Havent pulled them to see what they look like, tho.

Tomorrow I will also unplug the PC and see how it runs.

And how do I do a fuel pressure test? Is this reasonably easy to do at home?


Thanks for the help

 

[EarlyBird]

On a suzuki I am not sure, but I am going to assume there is a adapter that goes in between the tank and the fuel rail to install a gauge. I dont have one for a bike. I have a gauge for auto's only.

*I would start with the Pc3 removal first. Checking the plugs wouldnt hurt. It would give You an idea how its running.*

Check all your wiring connections too, to were your PC3 is tapped into the stock harness.

A compression test wouldnt hurt either... but again you need an adapter to go in to the spark plug hole and a compression gauge to do that. Just rules out the mechanical part of the engine.

 

[San Diego Busa]

Im a newb, but any chance it got switched out of A mode to one of the other ones?

 

[III]

Im a newb, but any chance it got switched out of A mode to one of the other ones?

The ECU resets it back to A whenever the bike gets turned off...so everytime you turn your bike on, you're in A-Mode no matter what you had it in when you turn it off.

 

[III]

Ugh... So the past week or so, I noticed the bike has been running poorly. Its running rougher, has noticeably less power, and takes significantly longer time to reach redline. Once I hit about 8.5k rpm, I can really feel the power drop off.

So my first thought was that I got water in the tank a couple weekends ago when I washed the bike. I heard what I thought sounded like a gurgling sound as I poured water over the tank rinsing the bike off (no hose at my apartment). I thought this was just the water filling under the little flapper that protects the key hole, and thought nothing of it. It also seemed to run just fine. But just in case, I drained the tank today, filled it with fresh gas, and put in some injector cleaner for good measure. It didnt make a difference.

My next thought was that maybe I accidentally pressed some of the buttons on the face of my PC3 usb, messing up my map. I re-loaded the Brock's map, and it still didnt fix the issue.

So now I am thinking it is my fuel pump. The past month or so it has been whining and making odd noises, but I havent noticed any poor performance until recently. Is there a simple DIY test a newbie wrencher could do at home to see if it is truly the pump, or do I need to take it in? Also anyone know of any good deals on a pump online?

Am I right in thinking its the pump? Are there other things I should look at?

I'm no expert, but I don't think it's fuel pump. If it's whizzing, it's working...or at least that's been my experience.

I'm thinking it's what EarlyBird suggested, especially since that's exactly what you went for when you first started troubleshooting. I'd definitely check the plugs, especially with the aftermarket pipe. They may have been fouled if the pc3 is acting up. What kind did you put in last time?

 

[San Diego Busa]

The ECU resets it back to A whenever the bike gets turned off...so everytime you turn your bike on, you're in A-Mode no matter what you had it in when you turn it off.

Ahh. Didnt know that.

Thanks

 

[fastblackblur]

I had very similar symptoms to yours on my liter bike recently. The bike would start no problem but wanted to fall on it's face when i first took off, it would smooth out a little and but was definetly way down on power. No smoke or anything, just not running right. Turned out I had a couple of dead coils. Replaced them and the bike is back to normal.

As stated earlier I would take off the PC and see if tht effects anything.
Once you've done that verify your getting spark.
I would also verify you don't have any loose tubes around the air intake.

There is a test to see if your fuel pump is working, it's in the service manual.

good luck

Gary

 

[danath 34]

again, thanks for the responses guys.

1) yeah, I checked the mode selector as well, just to be sure, as it does kinda feel like its stuck in C mode, and nope, its in A.

2) Going to pull the PC this weekend probably. We'll see what happens.

3) The fuel pump is not just whining like normal... It does a couple things. You know the whining it makes when you first turn on the bike as it pressurizes the fuel rail? Sometimes it simply does not stop, and continues whining that loud as the bike runs. Even when it doesnt do that, it is still considerably louder than normal when running. Also, the second thing it does, is sometimes when I turn the bike on initially and it pressurizes the fuel rail, it kinda cuts in and out as it does it, in almost a sputtering sound if that makes sense.

4) The spark plugs I didnt actually install myself. I had my mechanic check my valve clearances, and he told me he could install the plugs for free while he was in there. He put in some NGK Iridiums.

5) A fuel filter wouldnt clog that quickly, right? I was thinking a clogged fuel filter would be a much slower onset kind of thing. Am I correct?

 

[badassbusaboy]

It's the fuel pump alright. Mine did the same thing. Watch out because it will run lean up top. The best price I got on a new pump was $437.00. Dealer was $700.00. Let me know if you can't find one for around $437.00.

 

[JGGUNS]

It's the fuel pump alright. Mine did the same thing. Watch out because it will run lean up top. The best price I got on a new pump was $437.00. Dealer was $700.00. Let me know if you can't find one for around $437.00.

Holy crap!!! For a pump? That's absurd.

 

[EarlyBird]

Well it could be a pump or a faulity connection or a shorted connection. You didnt mention that there was more gone through on your busa. The valves being checked. Did the tech remove the tank when doing the valve clearance check? Did he bungee cord it back real tight... Bungee cord hooked to front fuel tank eyelet and pulled real tight towards the back of the bike... Usually passenger seat removed and the other end of the bungee hooked there. Could of pulled or stressed the fuel pump wiring? It just seems funny that after the work and upgrades you had done to your busa..... You are now having problems! I got 16.9k on mine and have quite a few bolt ons and a afr tuner installed and all is well currently. Just trying to help you out with your issues. When you go into your bike check all connections and routing of all wiring and pc3 wiring too.

 

[danath 34]

It's the fuel pump alright. Mine did the same thing. Watch out because it will run lean up top. The best price I got on a new pump was $437.00. Dealer was $700.00. Let me know if you can't find one for around $437.00.

Damn... that is expensive... Anyone think its worth it looking around for a salvaged or used pump?

Well it could be a pump or a faulity connection or a shorted connection. You didnt mention that there was more gone through on your busa. The valves being checked. Did the tech remove the tank when doing the valve clearance check? Did he bungee cord it back real tight... Bungee cord hooked to front fuel tank eyelet and pulled real tight towards the back of the bike... Usually passenger seat removed and the other end of the bungee hooked there. Could of pulled or stressed the fuel pump wiring? It just seems funny that after the work and upgrades you had done to your busa..... You are now having problems! I got 16.9k on mine and have quite a few bolt ons and a afr tuner installed and all is well currently. Just trying to help you out with your issues. When you go into your bike check all connections and routing of all wiring and pc3 wiring too.

Yeah I will check the wiring, but I saw him putting it back together, and he did completely remove the tank, so unless he tried bungee cording it back before he removed it, I dont think there should be stress on the wiring. I will open 'er up and take a look tho. And he checked the valves a couple weeks before I did the upgrades; it was bone stock. It then ran fine for the past month or so before this... And thing is, it seems to run OK in the low/mid range... You REALLY notice it on the top end, but if you werent looking for it, you might not notice a problem if you stayed in low/mid range... Its still ride-able. It almost just seems like the fuel pump isnt able to keep up with the demand for fuel in the upper range...

 

[EarlyBird]

From what you just told me in the post above... I would look at the Pc3 as the first place to go... then remove it. Then go ride it and try it out.



Go to this after you do the above:

If the problem is still there... then would have to agree it is a fuel pump issue. Also for what it is worth... see if the secondary throttle valves are working correctly.... You have to take the top of the air box off. Then look at the throttle bodies. The top butterflies are the secondary valves. When you turn the key on with ignition button on. They should cycle. I believe opening from 1/4 open to WOT to then a 1/4 open again. Just making sure that it isnt sticking. A code would be set I believe, during the test cycle when you first power up the busa. Also make sure your ram air ducts are not blocked with a rag or something. I have heard of weird things like that.... where some one left a rag in the air box... thank god before the filter. But it choked up the bike. It would idle and run at low speeds, but got to crap at WOT!.

 

[Bigdog5]

I had a buddy who had similar issues with his '08. He removed the PC3 and everything was fine!!

 

[badassbusaboy]

Before I got the new pump I tried the salvage yards. Busa parts was the first ,told me they had a good one that came off a good running bike. Well I got the pump put it on and nothing, so I sent that one back. Stike one. I ordered another one from cycletherapy they said it came off a 09 with low miles and plugged it in and worked. Well I got this one put it on bike started and ran good. Next day I was going for a ride and it took five times to start, So I called cycletherapy to see if I could take it apart to see if maybe the filter was clogged or something. They said ok, so I took it apart the filter was clean but when I pulled the pump out of the housing the nipple on the pump was broken right off. Pump was dropped or from the crash damage. Sent that one back strike two. I din['t want strike three so I ordered a new one and its perfect now. I just don't have luck with used parts.

 

[danath 34]

From what you just told me in the post above... I would look at the Pc3 as the first place to go... then remove it. Then go ride it and try it out.



Go to this after you do the above:

If the problem is still there... then would have to agree it is a fuel pump issue. Also for what it is worth... see if the secondary throttle valves are working correctly.... You have to take the top of the air box off. Then look at the throttle bodies. The top butterflies are the secondary valves. When you turn the key on with ignition button on. They should cycle. I believe opening from 1/4 open to WOT to then a 1/4 open again. Just making sure that it isnt sticking. A code would be set I believe, during the test cycle when you first power up the busa. Also make sure your ram air ducts are not blocked with a rag or something. I have heard of weird things like that.... where some one left a rag in the air box... thank god before the filter. But it choked up the bike. It would idle and run at low speeds, but got to crap at WOT!.

Ok, thanks, will do.
I should be able to pull the PC and give it a test ride tomorrow. Just been too busy this week to do much with it.
I'll also check out the throttle valves like you mentioned while Im at it.

Before I got the new pump I tried the salvage yards. Busa parts was the first ,told me they had a good one that came off a good running bike. Well I got the pump put it on and nothing, so I sent that one back. Stike one. I ordered another one from cycletherapy they said it came off a 09 with low miles and plugged it in and worked. Well I got this one put it on bike started and ran good. Next day I was going for a ride and it took five times to start, So I called cycletherapy to see if I could take it apart to see if maybe the filter was clogged or something. They said ok, so I took it apart the filter was clean but when I pulled the pump out of the housing the nipple on the pump was broken right off. Pump was dropped or from the crash damage. Sent that one back strike two. I din['t want strike three so I ordered a new one and its perfect now. I just don't have luck with used parts.

yeah, thats what Im worried about... I dunno, though, the chance of a much cheaper solution may be worth the risk of lost time... We'll see.

 

[danath 34]

So today I removed the PC3... still lacking power up top.

I also checked over all the wiring beforehand, and everything was good. Checked out all the hoses to the tank/pump, and all were good as well.

Double checked that I didnt leave a rag in the ram air ducts (didnt think I had, but you never know).

I also looked at what I think are the secondary throttle valves... If I understand correctly, I take off the top of the airbox, and should be able to see them towards the rear of the bike.... Im looking in the right place, right? (see pic)
When the key is off, they are all the way open. Turn the key on, fuel pump starts pressurizing, and there is no cycle like you were saying, they still stay 100% open. Then start the bike, and they close (or probably 1/4 open) and open up a bit as the throttle is turned.


Also, just to make sure, I did get the right hose for the pair valve, right? The one with the arrow and the little twist tie is the one I stuffed the marble into. Again, however, it ran fine for quite a while just like that, so I dont think its the issue.