Bro-n-law's '99 Road King died on the road, and won't start now. Cranks strong, but no start. Bike is a TC88 with Magnetti Marelli EFI, and was running fine until he came to a red light - bike sputtered, then it died. Past few weeks it's been showing a stored DTC 56 "crank/cam sensor signal error" but was running fine despite the stored code. There are no new codes since the bike died, still showing just the DTC56.

We put a new fuel pump in the bike a couple years back, and a new crank sensor. I don't think there's a cam sensor in the bike. I can hear the fuel pump come on & pressure up with the ignition. I pulled & cleaned the head of the crank sensor -it looked fine. I cleaned the crank sensor plug connections with brake cleaner. I pulled the plugs & checked for spark - plenty good spark at each plug. The plugs themselves look fine, no oil, no soot, and not running hot/lean. Still no start.

One thing I noticed while cranking & looking for spark at the plugs, was no gas smell. I'm thinking with the engine cranking & the plugs out we should smell gas, but no.

I don't think both injectors would die at the same time. Maybe they're not getting a signal to squirt? Any chance the Screaming Eagle fuel tuner/map thing crapped out?

Any & all advice much appreciated.

JR

 

It could be the tuner crapped out or even worse it could be the ECU took a dive. If the ECU died Harley now makes one that would replace the tuner and the ecu but requires custom programing at a dealer.

To test take the tuner out and see if she fires up. If not then it could be the injectors or the ECU.

 

comments:

brake cleaner is not contact cleaner ( you want a plastic safe contact cleaner to remove oxidization from the contacts)

machine says DTC 56 crank sensors, start there ( and as pointed out below, cam sensor too.*)

fuel pressure? is fuel pump making pressure and stopping or does it keep running? pump or lines.


do not crank motor with plugs pulled unless they are grounded- doing so can add a blown ignition on top of your original problem.

mike

*ronnies HD online microfiche has diagrams if you need

 

It does have a cam sensor also.

Toby

 

take plugs out put some gas in the spark plug holes put plugs backe in try starter it should fire it wont run but should fire if it fires the problem is gas My 08 did the smes thing you are saying yours does if it fires disconnect the quick disconnect at the tank plug it back in see if it runs if it does you need a new quick disconnect that all I know about that

 

Agree! As stated, also try dropping your piggy-back tuner. If you're confident there's good spark & no fuel, check pressure as Mike stated (I think MM is around 44 psi). If you don't have a gauge, look inside the tank & cycle the pump. If there's fuel pushing around in there you probably have a cracked/severed line.
Good luck!

 

How long ago did you replace the crank sensor? I've had the crank sensor cause a nostart 3 times, once on my 99 & twice on my 00. It was several years apart on the 00, but I had to replace it twice, I'm betting it's one of the sensors & I think the crank sensor controls the injectors, good luck.

 

Turn the switch on. If the fuel pump primes up and stops, try to start. If it does start and runs for only a few seconds and dies your Cam Position Sensor/Bank Angle Sensor has gone bad.

 

Wow, lotta good leads in those responses - thanks all.

I can hear the fuel pump running then stop, so I think it's building pressure. And yeah, I always ground the plug & watch for spark across the plug gap. Spark looks good.

I didn't know the crank sensor plays into the injectors. I was thinking it was just a signal the ECU used to time the plugs - I was probably wrong on that. Maybe the crank sensor is dead again - that would be an easy fix. I was thinking DTC 56 for this '99 is a signal error, little different from the DTC for dead crank sensor (DTC 41). Maybe the crank sensor isn't as durable as I thought and it is dead again.

For now, I'll put a little gas in the cylinders, or starter fluid in the intake, and see if the bike fires it off. If it fires, maybe it's a fuel or injector problem. I'll check the quick disconnect, and I'll remove the tuner & see what happens too. I'll pull the cover & see if there really is a cam sensor under there - I never actually checked. Really hoping it's not the ECU.

Thanks for all the input - much appreciated.

JR

 

If your problem is the ECM, dig around here on the forum or EBay and find a used one, should be able to find one for about $100. I replaced mine several years ago because the original had taken on water and shorted out my tuner. The ECM actually worked fine once dried out, I replaced it to be safe and to have the original as a spare.