No start/no spark.

Joined
Aug 18, 2026
Messages
4
Age
69
Location
Montreal
Bike
‘82 Honda CBX
Hola, new member looking for help. Searched the archived posts. No bueno.
Just replaced a faulty alternator on my buddy’s 2004 1300 w/109,000km. Was running fine before I replaced the alternator.
Now…no start/no spark and I have a code for the TPS (#8).
Battery fully charged, cranks fine, sidestand up/clutch in/neutral selected, fuel pump primes well and there’s pressure at the fuel rails. Voltages at the TPS connector are per the FSM. All the fuses seem ok.
Cleared the fault code but it keeps on coming back.
Any suggestions greatly appreciated.
Mike C.
 
If you had the throttle bodies removed, I think it is possible to have the TPS and MAP sensor connectors installed backwards. The TPS connector should be blue and the MAP connector grey.

The voltage wire color codes are the same as well as the voltage supplied.
 
If you had the throttle bodies removed, I think it is possible to have the TPS and MAP sensor connectors installed backwards. The TPS connector should be blue and the MAP connector grey.

The voltage wire color codes are the same as well as the voltage supplied.
BINGO! I had switched to connectors. Should have been: Grey to MAP sensor, Blue to TPS.
Thanks a bunch.
STILL no spark, or any volume from the injectors though 😥
Does it matter that I am trying to start it with the air filter housing (air temp sensor connected) and the upper fuel tank removed?
 
Last edited:
OK, The CMP sensor connector located in the valley at front of right head can be swapped with the purge solenoid on mid right side of frame at aft end of engine. Purge connector should be blue, CMP connector black. Having the upper tank off should not affect spark or fuel.

Are you getting a code 18 from the ECU?
 
Will check the connectors you mentioned.
After your input regarding the MAP sensor and TPS connectors I managed to clear the codes and there are no other current/stored ones.
 
DOH!
Thanks, Paul, for leading me in the right direction. Pulled back the rubber heat guard to discover I hadn’t reconnected the RH cam position sensor. Funny, I remember looking at it when dropping the alternator in and reminding myself NOT to forget it.
Strange there was no fault code.
Running smoothly and showing 14V @ 2,000rpm.😎
Huge ‘thank you’ for helping out.
Mike C.
 
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