Trouble in River City

We left Bloomington happy and confident after a good driving day the day before, and after getting a  good night' s rest.  Then trouble!  After driving about 10 miles the check engine light came on, and my Silverleaf engine monitoring system displayed a code indicating a loss of signal from the engine RPM sensor.  This has been a periodic problem.  This code seems to pop up once or twice every few years, and in fact came up just 10 minutes after leaving home on Saturday.  After stopping and shutting down the engine the code does not usually re-appear again, at least not for a while.  This sensor is actually one of two identical parts, one seeing crankcase speed and the other sensing camshaft speed.  If one fails completely the other will provide the same information to the engine computer.  If both fail the computer thinks the engine has stopped turning and cuts off fuel to the engine.  This means the coach stops and won't go no more.

A view from the SilverLeaf EMS

In the summer of 2011, while on our previous trip to Alaska, this same problem reared its ugly head. The code first occurred in Alaska but while we were starting to head towards home.  The first viable service opportunity was in Whitehorse, Yukon Territory.  We stopped there, and they confirmed my diagnosis of a bad speed sensor, but had no part in stock.  The next place on our route that had the part was Fort Saint John BC, almost 1500 miles beyond where we first observed the code.  Long story short, we had both sensors replaced in Fort Saint John.  It was an all day job and fairly expensive due to all the systems that had to be removed to access the sensors.  You can read about that experience here.

OK, so here we are near the beginning of a long trip. and we have had 2 identical "check engine" events in 3 days.  There was a Cummins service center about 100 miles west along our route, in Rock Island IL, near Davenport IA (both towns are on the Mississippi River and mentioned in "The Music Man", hence the reference to trouble in River City. From Wikipedia: The "river" in River City is probably the Mississippi River near Davenport, Iowa: the Rock Island conductor's announcing "River City, Iowa! Cigarettes illegal in this state" implies crossing the Mississippi from Rock Island, Illinois into Iowa.)  We made a call to Cummins and they could work us in.  Upon arrival the mechanic attached his scan tool to our engine data port and recorded a code indicating a single event of a lost engine sensor signal.

I hope he moves before we pull out!

The mechanic suggested the problem was a momentary "blip" with the sensor and was not persistent. He could not explain why it was occurring; could be a failing sensor, could be an iron particle or other debris on the magnet on the sensor, an electronic cable fault,  or one of several other problems.  There was no way to tell without removing the sensor ($$$$) and performing a more detailed analysis (delay!).  He did suggest the sensor was unlikely to fail completely any time soon, and that we were not likely to be stranded, and it would not damage any other engine parts.  We decided to let it be and continue on.  There were a number of Cummins service centers along our route, and we could always stop later if the problem worsened.

We left Cummins and immediately crossed the Mississippi River into Iowa.  Then the RPM error occurred again.  CRAP!.  We called Cummins and they said to come back.  They checked the ECM again and, once again, there was just one single occurrence of the error.  We again considered whether to have the sensors removed and the system tested.  Actually Dorcas and I debated for almost an hour.  She's a take no chances kinda girl, and my philosophy is: if it ain't really broke, don't spend over $1000 to fix it and lose a whole nother day to boot.  Finally we decided to head on and take our chances.  We still had more opportunities for a repair along our route if things turned for the worse.

In the meantime, the day turned into a scorcher. The high for the day was about 92 degrees.  But the temperature dropped substantially in the late afternoon as we skirted some thunderstorms.  After a  304 mile driving day, we pulled into the Walmart at Waterloo Iowa for the night.  Pretty good progress considering we spent almost 5 hours at the Cummins facility.  It would have been a nice quiet night if it weren't for the Chysler/Jeep dealership next door to to worry.  We were so tired it made no difference.

Parked at Camp Walmart Waterloo IA

By the way, check out our new Yakima Skybox.  I bought this off Criaig's List while in Florida, specifically for this trip.  It holds paddles, fishing rods, tackle, packs and a host of other relatively   light and bulky stuff that would ordinarily be in the way in the back of the car.

A new toy