Orion231 Posted August 20, 2009 Report Share Posted August 20, 2009 Ok gents here's the deal. This weekend I loaded up my '08 Buell 1125r and headed down to Hallett raceway for a trackday. The truck ran great all the way down there. Then the morning of the big day I sent my lovely wife out to grab some fuel in the VP can and return to the track before we started our warm up session. She came back and told me the truck was idling real funny and the O2s weren't bouncing like they should be. The first thing I asked her was if she was getting hard into the boost trying to show off, and she swore up and down she hadn't. I didn't have time to look at it because our track sessions were tightly scheduled. So we got a lunch break and I fired it up and the sucker was idling like crap and trying to die, which it did a couple of times. I revved it a little and it would smooth out and run ok but when the RPMs dropped it started to chug. I didn't hear any detonation and checked all my guages to make sure I didn't have any major issues. I didn't have much of a choice so I loaded everything up and told the truck to get us home and she did! I drove it real easy back home but on the Interstate it gave us no real problems, just when we woudl stop for fuel. On the way home I speculated that maybe I got some crappy fuel, or maybe the methanol injector was leaking, or perhaps the O2 sensor was going out but nothing really made sense. I do have EFI Live, but I didn't have it on me at the time, and the truck didn't not throw a service engine soon light. So here is my plan... Plan of Attack 1. Get off work tonight. 2. Hook up EFI Live, record idling and look for codes. 3. Reflash PCM with last tune from Texas rear Turbos. 4. Start at Turbocharger and clean K&N, check fittings, and charge pipes for leaks. 5. Work up to the MAF and check for debris/soilage. 6. Check injector for drip leaks. 7. Check grounds and sensor connections. Known Items... 1. Vaccum is steady. 2. No SES light. 3. Plugs are only a few months old. 4. MAF has been cleaned within 90 days. 5. Charge Piping has been cleaned within 90 Days. 6. After engine is at operating temp it will idle ok...but on throttle tip in it cuts out. 7. At cruising speed. It doesn't seem to have any issues. If I find the culprit in those steps I will be happy. The truck did this once before after I filled up on post with "premium" fuel and it ran like crap and idled like crap. As soon as the tank started to burn down I went to BP, and put some known good premium in it and it stopped! So I never worried about it. But even after filling up again down there at a station miles and miles away it was still doing it. So the question here is, anyone have any other ideas? And if anyone uses EFI Live and wants to give me a little hand I will send you the data logs to review. Thanks a lot! Quote Link to comment Share on other sites More sharing options...
Fireman31 Posted August 20, 2009 Report Share Posted August 20, 2009 Fuel in the VP can? Were you running leaded race gas? If so, what octane? Quote Link to comment Share on other sites More sharing options...
Orion231 Posted August 20, 2009 Author Report Share Posted August 20, 2009 (edited) Sorry... for clarification... the VP can was used to fill the bike. The truck gets premium fuel always. I try for 93 octane all the time if it is around. I just sent her out to fill it up for $2 and some change at a local station vs paying for premium fuel at the track for $4 and some change and the "convenience". Edited August 20, 2009 by Orion231 (see edit history) Quote Link to comment Share on other sites More sharing options...
Orion231 Posted August 23, 2009 Author Report Share Posted August 23, 2009 I feel like an idiot. I went out today and finally started to go through everything, I started at the Turbocharger and made my way up the charge pipes. I made it passed the MAF and up to the Throttle Body and lo and behold... The pipe had blown off... I could have fixed that in two seconds at the track but I was so damn tired and hot I just figured it to be the worst. Good thing is, it was only off a little so I don't think anything got sucked into the intake manifold. I just cannot believe I didn't put 30 seconds worth of effort into it and found/fixed the problem on the spot. Good thing is, $0 to fix it. Quote Link to comment Share on other sites More sharing options...
AKSSS Posted August 24, 2009 Report Share Posted August 24, 2009 I feel like an idiot. I went out today and finally started to go through everything, I started at the Turbocharger and made my way up the charge pipes. I made it passed the MAF and up to the Throttle Body and lo and behold... The pipe had blown off... I could have fixed that in two seconds at the track but I was so damn tired and hot I just figured it to be the worst. Good thing is, it was only off a little so I don't think anything got sucked into the intake manifold. I just cannot believe I didn't put 30 seconds worth of effort into it and found/fixed the problem on the spot. Good thing is, $0 to fix it. It always seems to be the quick and obvious fix that you just fly over anyways. I am kinda curious. Have you ran the truck at the track before? I haven't seen very many sts silverado numbers from the track. Just curious. I haven't ran mine yet. Still working on it before I do. Quote Link to comment Share on other sites More sharing options...
chpspecial Posted August 24, 2009 Report Share Posted August 24, 2009 12.5 at 109 mph... on 12# of boost and 7 cylinders... 7.79 1/8th of a mile on that run... and I lost sparkplug #7 around the 1/8th mile mark, so I think, but it was do to the #7 piston having blown ringlands, otherwise it might have been a high 11 pass Quote Link to comment Share on other sites More sharing options...
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