Poor starting

[scottr]

I recently purchased a 02' R1150RT with about 50K on the clock. It has had all the scheduled maintenance by a BMW dealer. It is a very poor starter.It takes me about four tries to get the thing started. Once warmed up, it will start again perfectly but the first start of the day is a challenge (and embarrassing) It doesn't seem to matter if I choke it or try and use the throttle or whatever. It just wont start until the fourth try and then with some throttle.

I have owned about 10 different BMW's and never had a starting problem. This thing should start without touching the throttle. Any suggestions of where to start in correcting the issue?

 

Thanks

Scott

[dirtrider]

Afternoon Scott

 

It could be as simple as a low capacity battery not allowing enough cranking voltage to run the fuel pump or properly power the ignition coils/fueling computer during cold start.

 

Or an engine sensor issue.

 

Or a fuel pressure issue.

 

OR-?????????

 

So first thing try a jumper cable from a non running car or other motorcycle to your battery for cold starting to see if that helps.

 

If that doesn't help then you need to get more serious with a GS-911 or dealer computer to see if all your engine sensors are working correctly. Or lacking those manually test all your sensors. (especially engine temp & intake air temp)

 

Maybe try removing fuse #5 for about 30 seconds then re-install --key on then do a new TPS re-learn throttle twist cycle.

 

Also you can use a known good spark plug (doesn't have to be for your engine), open the electrode gap to 3/16" (use a 3/16" drill bit as a gap gauge) then plug that into a spark plug wire & lay on the engine block. Then crank your cold engine (as you would start it) & see if you are getting a nice snappy bluish colored spark across that 3/16" gap (leave the original plugs is as a cranking load) . If not you have either low cranking voltage, or bad coils, or something causing the loss of cold start spark.

 

Next, maybe run a cold start fuel return hose fuel pressure flow test. Basically see if you have any fuel coming out of the fuel return hose during cold start. If not you have low pressure or low flow during cold starting (maybe a pump issue or hose issue inside the tank).

 

Otherwise run a cold engine cranking compression test to verify you have good cold cranking compression.

 

One last thought, if it has old gasoline or possibly gasoline with high alcohol in it try some new (fresh) gasoline. Water, or high alcohol, content, or stratified fuel can cause all kinds of cold starting issues.

 

[Michaelr11]

Check the clearance of intake and exhaust valves. Tight valves will make for difficult starting.

[scottr]

Thanks DR. I'll get busy with this and let you know how I make out. What is the step of removing fuse # 5 about ("do a new TPS re-learn throttle twist cycle") I don't quite get that one...

 

Scott

[dirtrider]

Afternoon Scott

 

The fueling computer in your bike (Ma 2.4) uses the TPS (throttle position sensor) to know how far the throttle plates are open so it knows how much fuel to squirt in. To do that correctly it needs to know the exact high & low travel thresholds.

 

On your 2002 BMW Ma 2.4 system that TPS sensor position is a learnable input.

 

So, to teach the fueling computer the absolute fully closed & wide open throttle positions you should do a TPS re-learn.

 

To do that-- first remove the #5 fuse for at least 30 seconds, then make sure the choke if fully OFF, then turn the key on (do not start engine), then FULLY open & close the throttle twice. That is all there is to it.

 

The above should be in your riders manual under battery replacement.

 

[scottr]

I'll try it thanks!