jeffro67 Posted July 3, 2010 Share Posted July 3, 2010 Well i'm still at it, and i think i may already know the answer to this question. But I'll ask anyway, cause i need some reassurance. 99 bird. k&n filter, vance & hines slip ons, pcII(no professional mapping). recently purchased and having a couple issues, i'll try to make a long story short! "fi" light came on, did "loom fix"---fi light is gone. Was just cruising along about 60 mph and tach dropped to 0, twice, but kept running. Thought it might have something to do with pcII, so i took it off to compare and symptom never reapeared. Put some seafoam in tank(about 3 ounces to a full tank) and drove it around trying to mimic the problem, didnt happen. But what DID happen was this: Now it runs real rough at idle, stumbles until it gets to about 3500 rpm then smooths out. Put the pcII back on, and it still runs like shit! What do the think .......Im guessing fuel pressure regulator? seems to be a common issue.. To check the fpr, do you remove the vaccuum hose and look for a fuel leak and that proves it? I wouldn't think the seafoam would have caused this in such a diluted quantity, or coincidence? any advice on how to fix this would be greatly appreciated, i just want to ride this thing, not keep fixing it! Quote Link to comment Share on other sites More sharing options...
cecome Posted July 3, 2010 Share Posted July 3, 2010 Not 100 % on this but the tach thing happened to me when my r/r went out. Might want to check the charging system. Only takes a minute. You can search for threads on r/r and it will fill you in. Quote Link to comment Share on other sites More sharing options...
Zero Knievel Posted July 3, 2010 Share Posted July 3, 2010 My thoughts. 1. K&N might be dirty. Buy a "recharge kit" because you WILL have to clean and re-oil it if you keep using it. Dirt would obstruct air intake but might be overcome at higher RPMs. 2. You have a non-standard air filter and aftermarket exhaust. You MUST re-map the ECM...hence the PCII. Air filter change you can get away with. Aftermarket exhaust might be a problem. 3. I have maps for your PCII, but they are based on stock equipment, so I can't say if you reconnect the PCII and use one of my maps it will fix anything. B-12 Chemtool/Seafoam should have cleaned out any fuel system issues. See if you can find someone with the same bike and K&N filter w/your make of aftermarket exhaust. Any map that they know works for them should work for you. Quote Link to comment Share on other sites More sharing options...
spicholy Posted July 3, 2010 Share Posted July 3, 2010 1: check the connector between your R/R and the stator. Mine toasted itself. A dead tach. was my signaling event. If that is in good shape, then..... 2: Try running some SeaFoam through it. May have some bad fuel or a goobered up fuel injector. Quote Link to comment Share on other sites More sharing options...
ironmike Posted July 3, 2010 Share Posted July 3, 2010 Aside from the other advice you're getting (which is pretty good by the way), you may be on to something re: the fuel pressure regulator (FPR)... I understand (from anecdotal sources) that poor fuel quality - especially that with ethanol/methanol/etc... additives - may be the suspected culprit. The FPR can go bad slowly or all at once - it depends on how severely the internal diaphragm may be compromised. If the membrane merely has pin hole(s) it tends to act up more slowly as pressure rises - and demand (engine load) increases. Symptoms can include throttle lag, sputtering, rough idle, and even sudden recovery under acceleration (like it cleared its throat and woke up!). If the membrane is further deteriorating (and it will...) you can forget the any sudden recovery incidents, and the residual symptoms only get worse - like it's running way too rich. If the membrane is fully torn/compromised, the vent lines flood with raw fuel and eventually flood the combustion chambers; that's why checking for raw fuel in the vent lines is a sure testing protocol. You typically lose cylinders 2 & 3 first - flooded, drowned plugs, cold exhaust headers (2 & 3 - if 1 & 4 are still running - don't try to touch!). In a worst case scenario, you can hydro-lock the engine with raw fuel - it will bypass the rings and contaminate the oil. The fix is relatively easy. The FPR is on the right end of the fuel rail (Lift the tank and it's right there). Disconnect, unbolt, replace with a new FPR, and ride. It's really that simple. Oh yeah, if you suspect any fuel may have gotten into the oil - I strongly recommend an oil/filter change before you ride. Quote Link to comment Share on other sites More sharing options...
jeffro67 Posted July 4, 2010 Author Share Posted July 4, 2010 Thanks for all the responses. a couple things to add. The bike idles real crappy with OR without the pcII on it, So i think that rules that out, i think? After i did the "loom fix" i peaked at the r/r plugs and they were good(no burned up ends) New battery was put in also, and i metered the battery when running to about 14.1 give or take. So the charging system seems good also. I was thinking it might be a clogged fuel filter also, but the bike only has 9,600 miles and the tank looks real clean inside, hope its not that! I guess i'm gonna check out the fpr tomorrow for leaks, possibly change the plugs while i'm at it Any spark plug recommendations? OR words of wisdom to changing them! the only reason i really think it's the FPR is from searching this site and seeing EXACTLY the same symptoms which was remedied by replacing the fpr! Thanks in advance, When i figure out the culprit I'll be sure to let everyone know. Quote Link to comment Share on other sites More sharing options...
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