I recently purchased a 2004 S4R with 96 miles on it. The bike is running extremely rich. Rich to the point of gas coming out of the joints in the exhaust pipes after or during a brief ride. Could this level of richness be caused by putting on a performance ECU? Any thoughts on what could be causing this? Regulator not regulating?
I haven't driven the bike for long stretches time since it is running so rich. (I am afraid of damaging the engine.) But i have never seen the bike run hotter than 177 degrees. Does that seem reasonable? I have read about a bad temp sensor causing issues in other places but would it be this rich?
The bike is running a full Arrow Carbon "Race" system, stock airbox and filter, and an unknown ECU. Supposedly the ECU was never changed but getting straight info from the previous owner has been difficult. I am seeking info on the ECU which I will post in another thread.
2004 and only 96 miles? Has any service or tuning ever been done to it?
A coolant temperature sensor can make the bike run rich if it fails. Your bike has two sensors, one for the gauges and one for the ECU. At speed in cool weather 177o is reasonable. I read your other post about the ECU. I can't give you a proper answer about the ECU, but if it is a DP unit or an after market reflash TPS and CO trim need to be set. Easiest way to sort this out is find someone with diagnostic software and an exhaust analyzer or bring the bike to a dealer.
96 miles on an '04? Are the timing belts and tires original? Brake fluid? Oil? If so, change the belts and fluids. You may want to hold out on the tires until you get the bike sorted out, but keep in mind traction might be limited.
Timing belts changed, new battery, brake and clutch fuilds changed, oil changed. As far as tuning for performance, not that I know of. Like I said I am not even sure if this is the stock ECU. From the looks of the plugs and exhaust pipes this bike has always run super rich. Since it seems most Ducatis run lean when stock I wonder if the ECU has been replaced and the TPS never reset...
I think I am going to spring for an ECU flash just so I know what I am dealing with. I plan on doing the bulk of the work on this bike myself so I am considering a VDSTS. I love this bike so working through these issues to get her right is definitely worth it.
Confirm that the 'return' fuel line (from the pressure regulator at the throttle bodies, back to the tank) isn't pinched or kinked.
That can happen when the tank is lifted and put back down.
Quote from: Speeddog on April 08, 2011, 02:21:18 PM
Confirm that the 'return' fuel line (from the pressure regulator at the throttle bodies, back to the tank) isn't pinched or kinked.
That can happen when the tank is lifted and put back down.
Forgot about that. The first thing to check, free is good [thumbsup]
Thanks for the ideas and feedback guys. [thumbsup] I'll into the temp sensor and return line.
It was a failing injector. It got so bad that the problem was immediately visible just by looking at the fuel spray. I swapped in a used injector, changed the oil because it was horribly diluted with fuel, and she fired tight up and purred like a kitten. WAY stronger that it ran when I first saw it. What goes wrong on an injector that it gets steadily worse over time is beyond me, but it was definitely just dumping fuel...
This bike was supposed to be "PRISTINE, PERFECT IMMACULATE". What that turned out to be was a bike that had been sitting for years with a totally gunked up fuel system, failing injector, and a cracked, leaking carbon fiber tank. It's all resolved now and I LOVE this monster.
Thanks for the info and ideas everyone.
Do yourself a favor and get the injectors flow matched from a local injector shop. Pretty inexpensive and is a def improvement
OK, now post a photo of it :D
And, did you get the OEM steel tank to go with?
No the guy that sold me the bike had already sold it on ebay.