The other day I had an unusual problem I took my 02 Road King out for a ride, I just finished installing plugs and changed the fluids, went about 20 miles and the bike was running great, I stopped at a friends house for a while and when I went to leave, I started the bike and it would run for 2-3 seconds and stop I tried several times to start the bike but it would not stay running, if I tried to twist the throttle it would rev high and quit in 2-3 seconds, had to trailer the bike home. next day I took the air cleaner off and looked at the throttle body and everything seemed to be connected, behind the throttle body there was a vacuum cap that seemed to be dry rotted replaced that and still the bike wouldnt start after several attempts the bike started and stayed running and today is still running ok I read thru the EFItutorial here and found a component called the IAC idle air control valve seems like it may possibly be the culprit not sure, not sure how to retrieve engine codes if one came up, and if someone thinks that could have been the problem do you know where this IAC valve is located, and how to replace it I put some miles on the bike and the problem has not duplicated itself not sure if I can trust it not to happen again though.
02 Road King starts/wont stay running
- Thread starter Wayne R
- Start date
Hoople
Account Removed
If you could not keep it running at a high RPM, it probably is Not the IAC.
The IAC sets the idle speed. Above idle, it really does not come into play.
Check for ECM codes. See help/links
Hoople
Account Removed
Just a far reaching wild guess but I would like to know what your fuel pressure was at the time of failure. It's almost like you lost fuel pressure due to the pump not starting up.
Be aware that even though you may have an IAC error code stored, it does not mean you need to change the IAC motor. The IAC does not send position feedback to the ECM. That means the ECM may "peg" the IAC in an attempt to maintain idle speed. If the idle speed still can not be maintained to the correct set point, the ECM will blame the IAC as being faulty for not stepping even though it's pegged and some other reason is causing the idle to drift.
Be aware that even though you may have an IAC error code stored, it does not mean you need to change the IAC motor. The IAC does not send position feedback to the ECM. That means the ECM may "peg" the IAC in an attempt to maintain idle speed. If the idle speed still can not be maintained to the correct set point, the ECM will blame the IAC as being faulty for not stepping even though it's pegged and some other reason is causing the idle to drift.
Hoople, not sure what the fuel pressure was when it wouldnt start I didnt smell any gas, and didnt see the engine light come on not sure if I have a stored code im gonna go out now to see if i can bring up a stored code saw in the self help section a codes and activation center gonna try that.
BUBBIE
Well-Known Member
JUST A QUESTION?????????? AND A CHECK FOR THE PROBLEM...
ARE WE SURE IT IS A LACK OF FUEL???????? or could it ELECTRICAL???
The way I (I) CHECK AND NOT WANTING TO SUGGEST A UNSAFE WAY TO CHECK..... but (BUT)......I would get a small (SMALL) Quantity of FUEL in a SPRAY BOTTLE... with the AIR COVER OFF spray a small amount to take over the IDLE and KEEP IT GOING at the IDLE....VERY SMALL amount of fuel ONLY!!!!
IF THIS WORKS,, and KEEPS RUNNING,,, IT IS STARVING FUEL.....
You can play with the spray to see if it is ONLY low or if the high speed is NOT working....... careful (CAREFUL) have a co2 type extinguisher available RIGHT THERE...
IF it DIES even with the added FUEL SPRAY it probably is the CAM or CRANK sensor..... COMMON ON THIS YEAR BIKE (my 2000 fxds)
signed....BUBBIE
Bubbie, I thought I had enough gas in the tank, I only had 140 miles on that tank of gas the needle was just under 1/4 of a tank the low fuel lite never came on, I did run the bike a little hard for a while though, Im thinking maybe it didnt have gas because its running fine since it started feel a little stupid if thats the problem but the bikes running strong since it started and im just gonna ride it until or if the problem happens again Thanks for all the help.
I was just going to post that you were probably running out of gas, as your symptom is just like what happens if main fuel is out, just before I turn the fuel valve to reserve.
One other thing on EFI bikes is to check the in tank fuel line for pin holes, causes fuel starvation, surging and erratic behavior.
http://www.hdtimeline.com/diagnostics_and_fuel_injection_related/979-engine_dies_and_runs_in_spurts.html
Glad you have sorted things out, reminds me why I like having reserve position on my fuel valve, and not have to rely on a fuel guage (odometer mileage method not withstanding).
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CalgaryBikeBum
Active Member
Also check that the rotten vacuum line is really connected well and its pulling the fuel petcock diaphragm open? No vacuum ..no Fuel. Or perhaps its pulling it partway open so it runs a bit then dies. Something to check.