| Author |
Message |
    
Biobuell
| | Posted on Wednesday, September 03, 2008 - 12:51 pm: | 
|
I'll start this off by saying I am NOT mechanically inclined, so tend to rely on the competence of mechanics. I took my XB12R in to a local bike mechanic for a routine spring service a month ago (I was unable to ride earlier in the season). When I picked it up, I noticed that when starting cold, it ran rough and stalled. If I gave it throttle, it would surge, nearly die, catch again, nearly die, surge, etc. It seemed to me that at least in part, it was starving for fuel. Once the bike was warmed up, after about four minutes, it ran fine, with great throttle response.
I then took it to a Harley dealership (did not do this earlier as nearest dealership is 150 miles away) to have problem resolved. Mechanic there said TPS was shot, and that the ECU was incorrect (stock) since I have the race muffler which was installed by previous owner. He replaced both, at no insignificant cost.
I picked up the bike this weekend, which required a trip back to dealer. When I went to start it, I noticed it still would not start properly when cold. Although the bike does not surge on cold start up, it still will not start cold without throttle, and acts as though it is starving for fuel until it warms up (only two minutes now). The dealer is aware of the situation, but I did not have the time to wait until they could re-examine it (it was a Saturday, Labour Day weekend, so they could not look at it until yesterday).
Two questions - 1. Any suggestion about what the underlying problem may be?
2. Was the ECU change necessary? The bike seemed to run fine with the old one, and before the problem surfaced, always started well.
I will have to take any solution back to the dealer, and be prepared to argue that the job was not done properly, so any information is appreciated.
Thanks, all.
Bill |
Biobuell
| | Posted on Thursday, September 04, 2008 - 11:46 am: |
|
Anyone have any suggestions, please. |
Sparky
| | Posted on Thursday, September 04, 2008 - 01:41 pm: |
|
It would be interesting to find out what the first shop's tech tinkered with that may have screwed up the cold start. He might have broken a sensor or one of the sensor's wires. There are sensors in the airbox, cylinder head, exhaust pipe and fairing, plus an exhaust valve in the muffler and its servo unit in the airbox.
Did the Check Engine Light ever come on giving an indication of a problem? If the TPS were indeed shot, I would think that there would be error codes stored for that problem. But they might be stored in the original stock ECM. You do have both ECMs now, right?
It's better to run the race ECM with the race muffler, but the bike will run with either ECM as long as the TPS reset procedure is performed correctly following a replacement of the ECM or TP sensor.
Have the dealer redo the TPS reset and check for error codes. |
Brewtus
| | Posted on Thursday, September 04, 2008 - 01:53 pm: |
|
I would have them check the spark plugs. Make sure they are the proper heat range and gapped correctly. It sounds like they could be fouled. |
Packrat
| | Posted on Thursday, September 04, 2008 - 05:53 pm: |
|
And something I learned from reading here.....DO NOT even touch the throttle when starting the bike...leave it alone for like 2-3 minutes, just idling on it's own....I guess this applies AFTER ya get it running right, sounds to me as though the ECM change was not necessary.... I run K&N filter, Special OPS tailgunner exhaust, and the STOCK ecm. I had the TPS reset with a race ECM hooked up, then hooked it right back up to the stock unit...it runs fine, no flat spot, etc,etc,etc, for the last 6,0000 miles. You do not HAVE to have the race unit is my point, at least on my bike.....the advice about spark plugs sounds like it just may fix your problem...if it does, I'd ask about them removing the new stuff they sold you, and see if all is well----let us know how it goes!! |
Biobuell
| | Posted on Thursday, September 04, 2008 - 07:50 pm: |
|
Thanks to all of you for great information.
Sparky, tech did routine service - checked air filter, oil filter, changed oil, lubed cables - but maybe in checking air filter did something to sensor or sensor wire in airbox? Check Engine Light never came on, but I do have both ECM's, so can check for error codes. No exhaust valve, as this is the race muffler. Prior to this problem developing, I never noticed any running problems associated with running the race exhaust and stock ECM, which is consistent with your advice.
Brewtus - plugs were fouled after problem began, but dealer tech changed them (and he is supposed to be a Buell tech so hopefully he got gap and heat range right). However, with bike starting like it does, it would not surprise me if they are fouled again.
Packrat - Normally I can leave the throttle alone when starting - not now, or it dies. As I just noted, spark plugs were fouled, but were changed, so that isn't the current problem. However, you too have confirmed what I suspected - stock ECM was not part of problem or solution.
Thanks to you all for your help. Now I just have to take the opportunity to get this sorted out - difficult with the dealer so far away, but oh well. |
Bombardier
| | Posted on Thursday, September 04, 2008 - 09:33 pm: |
|
Sounds like an AFV reset is in order. |
Brewtus
| | Posted on Thursday, September 04, 2008 - 10:11 pm: |
|
OK, the next step I would perform was a TPS reset(again) and like stated before AFV reset. (Make sure the tech knows how to reset the TPS properly. Lots of info here on how to do it.) i would do both at the same time. I would also check to make sure the intake air temp. sensor is plugged in.
If you would like I can lend you my VDSTS cable and walk you through the steps on the TPS and AFV reset. PM me if interested.
Please post back on results.
Rob
(Message edited by brewtus on September 04, 2008) |
Biobuell
| | Posted on Monday, September 08, 2008 - 01:12 pm: |
|
Bombardier and Brewtus,
Thanks for the additional information. I will certainly add your suggestions as to what should be done. At present, I am reluctant to do the TPS and AFV resets, but may take you up on this when riding season ends. Meantime, I will certainly repost once I have a chance to get dealership to revisit and hopefully address my problems.
Thanks once again, and in particular thanks to you, Brewtus for your generous offer of assistance with the VTSDS cable.
Bill |
Bombardier
| | Posted on Monday, September 08, 2008 - 11:33 pm: |
|
Find out what your AFV is currently by using VDSTS or ECMSpy.
If its over 100 I would say that there may be an induction leak.
It could something as simple as the little rubber cap is missing from the side of the throttle body or your inlet gaskets are no good. |
|
Troubleshooting (Poor Starting/Running/Handling/Ride Issues) »
Archive through September 10, 2008 »
Cold Start Issues - 2004 XB12R