We finally escaped Livingston after 6 loooooong weeks.
If you remember all the way back to the last blog post, we had to wait a few weeks to get the HOW into a reputable shop to find out what was wrong. When that day finally arrived we limped it in for its service appointment. The mechanics noticed right off that the catalytic converter was glowing. They thought at first that some blockage downstream in the exhaust path caused the cat to overheat, which in turn told the ECM (Engine Control Module) or in the case of the HOW, the PCM (Power Control Module) to go into kind of a safety mode to avoid damage to the engine. There wasn't anywhere that carried replacement catalytic converters for 15-year old RVs, so we had to limp it back to Rainbows End, four miles (uphill) up the highway while one was ordered.
The new cat arrived in three days, but by then not only was it the day before Thanksgiving, but they had no openings to install it for two weeks. This garage is well known for its quality service, and since they're the only game in town, they are booked up weeks in advance.
We passed our time for two weeks and finally it was our day to get the HOW back to the shop. The mechanics removed the old cat and checked downstream for blockage. Nada! They reset the error codes in the computer and ran the engine a bit. The check engine light came back on and the computer threw the same codes as before. The cat was not the problem, but was collateral damage resulting from something else. They trouble shot from the COPs (Coil on Plug) backward towards the battery, and found that there was a complete circuit going into the PCM, but there was no ground coming back out on the way to the COPs. No ground equals open circuit. Open circuit to the COPs means no power to the spark plugs. So there was no spark on the entire bank of 5 cylinders on the driver's side.
Since the computer was wonky, it continued sending fuel to those dead cylinders, and since there was no spark, the unburned fuel exited the cylinders on the exhaust stroke and sent it through to the catalytic converter. The catalytic converter's job is to get hot enough to ignite any unburnt fuel that happens to make it into the exhaust system. When you dump half of the raw gas needed to propel a vehicle down the road, (in the HOW's case that's usually about 7.5 MPG), into the exhaust that cat gets hot enough to glow orange. That amount of heat will disintegrate the ceramic honeycomb inside the cat.
Now... if you can't find a cat for a 15-year old RV locally, there ain't no way you're gonna find a PCM. It would have to be sent to Houston to be rebuilt. This time we were assured that as soon as the computer came back they would get us in and install it and the new cat. In the mean time, the mechanic rammed a pipe through the old cat so it was kinda sorta usable and told us that since we needed to be able to drive the HOW, (after all it IS our house), he'd come by the next day to pull the PCM so it could be sent out.
Back to Rainbow's End. Again...
While we waited, we figured we'd replace the 15-year old toilet, so we ordered on of those. Finally, after some calls back and forth to the shop so they could give the computer rebuilder guy detailed information about the HOW, so he'd know what he needed to do to match the computer to the motorhome, the PCM came back, and it got installed along with the new cat and a shiny new toilet. They drove it around, I (Paul) drove it around, and all seemed well with the HOW.
Turns out there was a technical bulletin on the very problem we experienced on our computer. What sucked was that the tech bulletin was released a couple of years after many vehicles with the same computer were already out on the street. It wasn't a recall, but more of a heads up to the dealerships, that if they see vehicles with the problem, they should swap out the PCM at no cost. Of course there is no recourse this long after the fact.
Well, so it goes. We headed south to get back on track with our plans to spend some time on the Gulf of Mexico, before heading to Hondo. We gave up on the idea of going to Arizona since this little delay ate up a lot of our winter budget.
We arrived at Galveston Island State Park, weeks late, but glad to be there. I was on Galveston Island decades ago on one of the Cheap Trick tours I worked. It was dreary, wet and cold then, and it was dreary wet and cold this time! We got down to the beach the first afternoon so Penny could see the ocean.
After that it rained and got really cold. It rained so much that some of the campsites flooded. It never dried out enough to return to the beach; even for the one stretch of a couple of hours of sunshine.
We did get to enjoy some of the local flora. There was some kind of little burs that stuck on and on everything: shoes, socks, feet, tires, you name it
As is often the case, the morning of our departure was gorgeous. While we were driving to the park exit we noticed that at 35 MPH, the engine RPMs were only around 1700, and the rig was shuddering. Now I know that when a vehicle's computer is reset back to its default, it can take some time to "learn" how you drive. After a while that went away and all seemed fine again. Once we got up to highway speed I noticed that whenever the How downshifted to go up a hill, it shuddered like before. THAT did not go away.
We decided we had better give up on the rest of our Gulf tour, and beat it to Hondo where I could check it out. After lots of Internet research, I was able to ascertain that one of two thing may be wrong. One is that the transmission fluid is bad. When we were driving the rig in its disabled state, the engine would rev up to the 4000 - 4500 RPM range, and wouldn't shift properly. I'll have the fluid flushed and replaced, and then drive up into the Hills Country so I can do a shakedown. If that ain't it, I'll find a way to reprogram the PCM since that controls the transmission as well as the engine. If that ain't it either... I'll cross that bridge if I get to it.
Wish us luck, and stay tuned...
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