[2amcorner]

Bike would crank but not turn over unless I held the throttle open until it reached a certain temperature. I would go for a ride hang out for an hour and bike would start right up. Next day same problem. It has been colder lately, but being in Florida when the sun is up its still bloody hot and same issue. No codes present. Bike has 25k miles and figured I would check the valves again. Fuses and Relays are all good. All of them were out of spec. Put them in spec and still same issue. I started getting C21 Intake air temp sensor about 6 months ago and replaced it with another one and the code still wouldn't go away until one day it was and didn't reappear until the first retrying of starting bike after valve adjustment. Checked Battery and recharged anyways. Checked Voltage and Resistance all good. Unplugged and reconnected everything I disconnected and sprayed some contact cleaner. Still getting C21 and then started to get C28 Throttle valve motor and C29 Throttle Position Sensor 2 as well. Checked the Voltage and Resistance and still all good. C28 and C29 went away when I unplugged the ECU connectors.

Disconnecting the ECU connectors will erase the codes unless the problem still persists, but I am still getting C21 and no start. Replaced Fuel Pump with a spare and the C21 went away until taking taking tank off and back on. Tried spraying some Brake clean "Green bottle" and still no start. Checked throttle cables, Clutch as well as readjusting clutch with major adjustment. Have tried new gas, spare starter switch. Fuses were checked through out all the steps taken. I have a new IAT sensor coming tomorrow, but still confused because the bike should still start with it disconnected. I can get the bike to start by holding the throttle open just a bit and keeping it held open, but as soon as I release it and it dies. I've adjusted the throttle cable and still same thing. It's been almost a month of no riding. Way too long. Please help.

 

[2amcorner]

Swapped ECM problems gone.

 

[Mb1500]

Glad you got it sorted!

 

[2amcorner]

Unfortunately something else is going on. New ECM did fix the no start and codes popping up, but as soon as I try to take off it sputters and doesn't want to go far. I got the new ECM off Ebay and it has a Brocks sticker on it, but I think its fuel maps are stock. Cheaper flash "Stage 1". I know he recently started to offer a stage 1 that would make the exhaust codes go away, Fan kicking in earlier, Top speed limiter removal and then a stage 2 that would also come with updated fuel maps. So not sure if what I am experiencing is because of the full exhaust and Sprint filter, but I would assume that it shouldn't be acting like this. Have a throttle body coming Tuesday as well as primary injectors. Will keep this updated until resolved.

 

[sandpalm]

I have similar issues with my bike (same model / year) and am just about ready to replace the ECM, now I'm not so sure. I'm not ready to give up and move on just yet so I will update as well if I get it resolved; hopefully you can get yours sorted.

Agreed, I don't believe your exhaust / filter is causing the issue.