THE BIKE: 2002 R1150RT with about 40000 miles.
THE PROBLEM: The bike will start nicely and run for about 5 minutes on choke, then run rough, then die. This happened with a cold bike in a cold garage (20-30 deg) while the bike is on the stand. Same issue if the choke was turned off after a couple minutes. It would usually restart after 10 to 15 minutes. (Thermal issue?).
WORK I DID: new coil, new spark plugs and wires, new fuel filter and internal tank lines, new external quick disconnects, new HES sensor and lines.
DIAGNOSTICS: An aftermarket error reader shows no error codes. when the engine ran rough, the Lambda voltage (O2 sensor) would oscillate, and the bike stopped. (Possibly a problem in the software transition region from using no O2 sensor to the closed loop feedback using the sensor). I replaced the O2 sensor with a used one from eBay and the Lambda sensor voltage oscillation was gone. The bike still stopped after 5 minutes. I’m out of my league.
BMW DEALER: They did a valve adjust, fuel injector cleaning and test. Fuel spray pattern looked good. They measured pump output at 2.8 bar, the lower pressure limit. New plugs were black. The dealer mechanic says that the plugs are getting spark when the problem occurs. He has ruled out electronic problems.
BMW mechanic replaced the fuel pump (new aftermarket brand) and all internal hoses. No improvement, with the pump pressure still 2.8 bar.
CURRENT STATUS: mechanic thinks the next step is to replace the fuel regulator. I’m sure he’s right, but this is very expensive at the dealer, and I’m not interested in doing it myself.
HELP NEEDED: Has anyone seen this problem and can provide me with any information or alternate directions to investigate?
Sorry for the length of the post!
THE PROBLEM: The bike will start nicely and run for about 5 minutes on choke, then run rough, then die. This happened with a cold bike in a cold garage (20-30 deg) while the bike is on the stand. Same issue if the choke was turned off after a couple minutes. It would usually restart after 10 to 15 minutes. (Thermal issue?).
WORK I DID: new coil, new spark plugs and wires, new fuel filter and internal tank lines, new external quick disconnects, new HES sensor and lines.
DIAGNOSTICS: An aftermarket error reader shows no error codes. when the engine ran rough, the Lambda voltage (O2 sensor) would oscillate, and the bike stopped. (Possibly a problem in the software transition region from using no O2 sensor to the closed loop feedback using the sensor). I replaced the O2 sensor with a used one from eBay and the Lambda sensor voltage oscillation was gone. The bike still stopped after 5 minutes. I’m out of my league.
BMW DEALER: They did a valve adjust, fuel injector cleaning and test. Fuel spray pattern looked good. They measured pump output at 2.8 bar, the lower pressure limit. New plugs were black. The dealer mechanic says that the plugs are getting spark when the problem occurs. He has ruled out electronic problems.
BMW mechanic replaced the fuel pump (new aftermarket brand) and all internal hoses. No improvement, with the pump pressure still 2.8 bar.
CURRENT STATUS: mechanic thinks the next step is to replace the fuel regulator. I’m sure he’s right, but this is very expensive at the dealer, and I’m not interested in doing it myself.
HELP NEEDED: Has anyone seen this problem and can provide me with any information or alternate directions to investigate?
Sorry for the length of the post!