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Cfboss
Posted on Tuesday, May 29, 2012 - 09:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Looking for some diagnostic help. I was at a track day last weekend and ran 1 session great but the 2nd session the bike would stumble and not rev above 6000 without missing. I let it sit while I looked things over. 3rd session I reset the TPS and the bike had cooled off a bit and ran great. 4th session bike ran great to 6000, but acted like it was hitting the rev limiter.
I pulled the codes and got P0087 only. Doing some research, I see that it can possibly be a fuel pump or a pressure sensor. The bike is a May 08 build. Any other possibilities? I really don't want to take it to my lousy dealer. They are an established chrome installer and little else. How do I check fuel pressure and volts in Diagnostic mode? I don't have the owners manual.

Track day was still fun. I'll post a video soon.

Thanks.
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Methyman
Posted on Tuesday, May 29, 2012 - 10:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If you had the Electrical Diagnostic Manual it would be a great help to you. P0087 is fuel pressure sensor too low. The book has a great trouble shooting tree to follow. Part # 99949-08Y it retails for $60 but can find it cheaper on line.
http://www.lshd1.com/servlet/Categories
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S21125r
Posted on Tuesday, May 29, 2012 - 12:21 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Manual says should be 75 PSI at ignition ON, and between 55-60 PSI while engine is running. I have some Tuner Pro logs that show mostly between 55-60 PSI but does climb in the 60-70 range for higher RPMs.
You can read Pressure in Diag mode but it will be in KPA so you'd have to multiply it by .14503. Also it will exit Diag mode as soon as you start moving so you'd have to disconnect the VSS sensor temporarily. Alternately you could log via Tuner pro to see what your actual Pressures are in PSI.
If you do confirm through one of the above means that you have low pressure then you'd have to check for "restricted fuel pump inlet screen" If not clogged then replace fuel PRESSURE SENSOR. If clogged then clean it and all lines then retest. If it fails this second test then replace fuel PUMP.
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S21125r
Posted on Tuesday, May 29, 2012 - 12:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"If clogged then clean it and all lines then retest. If it fails this second test then replace fuel PUMP."

My Bad... "that should read Flush tanks and fuel lines. Refill with fresh fuel and retest. If P0087 still sets then replace FUEL PUMP"
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Cfboss
Posted on Tuesday, July 10, 2012 - 09:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Hey guys, I'm still fighting this issue. Since my original posting, I replaced the fuel pressure sensor hoping it would solve the issue. Here is what I'm experiencing: It's a track only bike, so I don't have any experience with it on the street. The last track day, I ran two 20 minute sessions with no issues. On the third session, the bike would not rev past about 6K, above that it felt like it was starving for fuel, below that it was fine. The CEL came on. If I short shifted, it was OK. By the second lap it ran fine again. 4th session, same thing, but issue went away by half lap. I can't imagine a bad fuel pump would act this way. Any ideas?
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