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cam sensor question

I'm curious as well. Just waiting for the rain to stop.
I soldered in a 250 ohm resistor with each resistor. Luckily I happened to have some from another project. In hindsight I should have used the green led on the signal wire as it is much easier to see when lit. I have plenty of time to kill as it will be 6 days (including the weekend) for harley to get the sensor. I just want to be sure before I give the ok for a non returnable part. The bike owner is away so time is not a big deal.
 
Ok, I went for a ride tonight with my wife (wasn't a good idea) and at first the bike ran flawlessly. The green led was on steady and bright and the red led was blinking. I mounted the leds just under and beside the ign switch so I could clearly see them while riding.

After stopping for a bit, I restarted the bike and noticed the red led wasnt blinking, it was on steady. I thought this was strange and then the bike stalled. I started it approx 8 times and each time it ran for about 5 secs. red led on steady and then it stalled.

After waiting about 10 minutes I tried again and this time the red led was blinking so I headed for home. It stalled in traffic about a half a dozen times (remember my wife was with me) and each time the red led stopped blinking just before the check engine light came on. I should also note that the green led was always on as long as the ign was on and the red led stayed on steady whenever it stalled. The intensity of the leds did not change when it stalled.

I believe I am going to order that cam sensor now. Thanks for the led idea hoople. I'll let you know when I install the new sensor and I'm going to research this ecm and see about convincing the owner on getting some software and a cable.

Sorry one more thing. Just out of curiosity, I unplugged the cam sensor connector and then I tried starting the bike. It starts, runs for about 3 - 5 seconds then stalls.
I also unplugged the sensor with the bike running and the check engine light came on and then it stalled about 3 seconds later......just like it was stalling on me.
 
tech2 said:
I unplugged the cam sensor connector and then I tried starting the bike. It starts, runs for about 3 - 5 seconds then stalls.
Click to expand...

Wow, no kidding. Without a cam sensor signal, the engine will start and run for 3 seconds.. That must mean the ECM gives the engine some kind of grace period to learn and come into phase with the ECM. It can start and run using only the crank sensor signal. I guess that also would mean for the 1st couple of seconds, the ignition and injectors may be firing on both TDC of compression and TDC of the exhaust stroke (or until it sync's using the cam sensor signal)

But to start & then run for 3 seconds.... That indeed is a strange one.
I would have guessed that the engine would not have started without a cam sensor signal.
That's good info..
 
Hoople, I am much more familiar with cars than bikes. I'm actually just getting back into riding. I do know that a lost cam signal on a car sometimes just means the check engine light comes on. No driveability complaint.

I wonder if the coils on the bike are fired at TDC (same as waste spark) from the crank signal until it gets an accurate cam signal. I believe the crank signal is the heart beat and the cam signal is for accuracy.
I'm wondering if the VAS portion of the cam signal being lost is the only reason why it quits? I am very curious about this. Any insight from anyone would be very much appreciated. I must say that being a newbie to this site, it sure is nice to be able to bounce ideas back and forth when problem solving. I have been reading some of the other forums on this site and there certainly are a lot of very knowledgeable people on this site.
Thanks
 
do you know a friend with a simular model bike? swap out for his module.
not bragging but rideing a tri glide i carry a spare cam sensor.also can't find in your profile where your at.
 
Thanks. I don't know anyone with the same bike, I'm just getting back into riding (it's been 25 + years). I am north of the border and will update my profile.
I have bit the bullet and ordered the cam sensor so it's already on my Visa card.
I'll let you know how it turns out. I'm pretty confident that's the problem but my fingers are still crossed.
 
tech2 said:
I wonder if the coils on the bike are fired at TDC (same as waste spark) from the crank signal until it gets an accurate cam signal.
Click to expand...

I know that the late model (Delphi) fuel injection systems are SFI or sequential. That I am sure of. So the ECM does phase to the engine and there is no waste spark firings. The early MM systems may be MPFI or port injection but I strongly doubt it. Since your bike does have a 'single fire' coil, it would only make sense that the FI system would also be sequential.

I guess you could run the engine without any phasing and just fire the injectors & plugs on every TDC of the crank, but the fuel milage, emissions and chance of backfiring would be horrendous.

So I guess what happens is the ECM starts the engine without phasing in order to "kick it off" on the 1st revolution (unlike the late model Delphi's which must revolve more than once). Then once started, it will sync the cam signal and now the engine becomes true sequential fuel injection.
You would have the best of both worlds... easy starting on the 1st revolution plus true sequential FI.
 
Hoople, you are a man of wisdom. I guess the area that confuses me is why would the bike stall after loosing the cam sensor signal. Once the bike see's the cam signal and starts, it is in sync. with the crank signal. From that point on, as long as the crank signal exists, the computer knows where the cam position is by it's first signal.
I wonder if the bikes that have a bank angle sensor mounted under the seat would stall if they lost the cam signal when running? I keep thinking it's about the built in VAS in the cam sensor shutting the ignition off when the bike angle is exceeded.
 
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