Bad fuel pump or something else?

[rbj69]

Hey everybody, hopefully you can help me out a little here. My bike started sputtering a bit on the highway at constant speed. Noticed it about a week ago. Then it started happening a little more often. The other day I am riding and it is perfect, no problems. Then after riding around most of the day it starts again, but much worse. It went from a skip/misfire feeling to a buck. The rpm needle would jump or dive and it felt like it was trying to die. This happened the whole way home regardless of throttle application. The next morning it started and immediately shut off. I tried holding the throttle open and not touching it to see if I could get it to idle, but it shuts off immediately. Just tried again and it wont even start now. The fuel pump comes on, but sounds a little different.

-Has plenty of gas (I would be the one to run out and not notice)
-Checked and cleaned the fuel pump wire connector, didn't notice any chaffing on wires.
-cant hook ecmspy up to troubleshoot because it wont crank. I think it has to be running anyway.

I am about to start checking voltages with my multimeter. Normally I wouldn't post until after I checked everything I could, but I am suppose to be moving in under two weeks! So I need any and all help I can get. Thanks guys!

 

[07Bolt]

If its a 03-07 XB then it might be the regulator. Check the regulator connection down beside cam cover. Check battery connections to.

 

[Thaloc]

I was just coming to post something very similar. Just as I'm about to sell her too... my luck.

2008 XB12R

Anyhow I had a very similar experience recently. We had just had a heavy two day rain and I didnt roll the bike into the garage. Its got a full tank of ethanol free gas. I went out for a ride the next day and it just lost power, almost like running on on cylinder for a second, then died. For the next week it would run fine for the most part, but about once a ride it would start to chug a bit and begin to lose power. If I pulled the clutch and gave her a little rev she cleared right up and ran fine the rest of the ride.

I figured I got some water into the fuel somehow so I put in a bit of Seafoam and road her twice since then. Now she wont start. I dont hear my Fuel pump priming at all, I check the fuses and wires and they are fine. I also hear an odd noise coming from my intake manifold, its very quite though so it could have been there the whole time but just drowned out by the Fuel Pump when it worked. But thats all I can hear now when I switch to run, a slight ticking from a black cylinder connected to the manifold that the fuel line leads into.

When I get home I'll check to see what codes she is throwing, hopefully it is just the pump. In that case ill be looking for a used pump if any of y'all got a lead on one.

RBJ69, here is a link to get error codes w/o software;

http://bcrider.com/DDFI.html

 

[Infernorodz]

Chk fuel relay. Sub frame grnd. Batt vlt. Fuses.

 

[Thaloc]

http://www.ebay.com/itm/New-Intank-...Parts_Accessories&hash=item4174709b3c&vxp=mtr

Is this too good to be true. It feels like it must be.

 

[Infernorodz]

I actually just purchased a fuel pump for 03 v6 mustang $38 it works fine eBay.

 

[rbj69]

Thanks, that's good news about the fuel pump. I thought it would be more expensive. I checked the fuses, regulator clip, and battery. The battery was at about 12.4v. I put it on charge just to be sure and then swap the relays to check them. The ground is under the air box right? Still need to check that.

Hope you get yours figured out Thaloc. Thanks for the link.

 

[snrusnak]

Not sure this will help at all but figured I'd post this info here. I had fuel pump issues a few months ago and here's what I did: (very detailed)

http://www.buellxb.com/Buell-XB-For...el-pump-fix.-Cheaper-than-replacement-from-HD

I found that my fuel pump ground(inside the tank) was actually loose. I assume this was my problem, or the cause of my fuel pump going bad(didn't test it, figured while I was in there just replaced it and move on, since it was only ~$100 for the mustang pump).

 

[rbj69]

Battery charged to around 14v. After sitting it dropped to 12.75. Bike turned over but still wouldn't crank. When cranking, it dropped a couple volts then went back up after shutting off. I switched the relays around and still no luck, everything stayed the same.

Thanks for the write up link snrusnak. That will definitely be helpful if I end up replacing the pump/filter.

I did bypass the start/stop switch a while back. It is on whenever the bike is on. Don't know if that could cause any issues. Maybe the wires came loose inside the switch housing and aren't getting good contact. Fuel pump still primes every time though, just sounds a little different.

Going to pull the airbox off and spray some starting fluid to see if it is in fact fuel related. Hopefully tonight, maybe tomorrow.

 

[rbj69]

Ok I got it running...for now. Tried spraying starter fluid in the throttle body and it didn't want to start. Then I noticed a little elbow coming off the throttle body that I thought I capped off. Looks like its for a vac line or something. I put my finger over it and it almost started. Then I noticed the breather for the crank case reroute deal was still off. Put it back on and she started right up. Stayed running so I took her out for a ride and ran perfect. Went out again and it started doing the skipping again. Checked the battery voltage and it wasn't going up with it running. Thought it was supposed to be above 13v while running.

 

[snrusnak]

FYI that little elbow on the throttle body is for california model emissions only. They are always uncapped, I don't know that it matters. I capped mine.

 

[rbj69]

The bike died again today. It idled for about 15 seconds and killed over. It still turns over and everything like before, just wont crank. Battery voltage checks out at about 12.7. I was beginning to think it was the voltage regulator, but even if that went out, the battery should still crank it. I guess something I messed with before was the culprit, I just need to start narrowing it down.

 

[Infernorodz]

If you sprayed starting fluid and it didn't fire you either have no spark (possible wrong timing) or no compression. Starts simple especially if frustrated. Chk signal to plugs, to coil, make sure you have spark in cyl plugs may be fouled. Then compression if you still can no run also chk timing.

 

[snrusnak]

If you haven't already done it I'd try plugs. My bike backfired real bad/continuously one time when the battery terminals were loose and after that I couldn't get it to start or even attempt to fire for a month worth of working on it. I changed the plugs and it fired right up. These bikes foul plugs very easy. Might not be the problem but it's a cheap/easy starting point.

 

[rbj69]

Thanks guys, I bet one of the two will be the culprit. Its in a U-haul now so I will check those when I get situated and report back.

 

[rbj69]

Thought I solved the problem. One of the plug wires was loose on the coil. Snugged it back up and this time it started and idled fine, even when opening the throttle. Before it would die as soon as I hit the throttle. Took her out and after about 4 or 5 minutes she started doing the misfire again so I hurried home. Hooked up ecmspy and ran all diagnostics (everything completed) and did a tps reset. There were no current codes, but 2 stored. Code 11 Tps short to ground and Code 15 air intake sensor shorted to supply voltage or open. After the tps reset it seemed to run a little stronger, but still ended up doing the misfire deal. Maybe something related to one of the stored codes?

 

[Infernorodz]

Make sure your all plugged in I've forgotten to plug in the ais... Try a wiggle test for shorts then test each sensor per service manual... That's about all you can do for those... Good luck

 

[rbj69]

Turns out my breather filter from the oil line reroute was the culprit. It was filthy! Won't let it get like that again. Thanks for all the help guys.