We purchased a 2003 Holiday Rambler with a GM 8.1 Workhorse Engine. It appears to be in great shape visually, only has 20K miles on the engine, but when driving it on the freeway the other day the check engine light came on and I lost power. Luckily I was able to limp to the off ramp and into a shopping center. I had it towed to the Chevy Dealership and they have now had it for several days. I received a call that they tested it and code 202 came up which is for the O2 sensors. They said they cleared the codes and test drove it and all is fine so far. They said that they want to put more miles on it to see if they can get it to trip the code again so that they can determine what is causing the problem. I am concerned that the issue has really not been solved with clearing the codes and that it may reappear at some later date. Should I have them replace the O2 Sensors even if they can't get it to trip the code with test driving? Any insights, advice and past experience is always greatly appreciated and Happy Holidays!

I have the same 8.1L engine and occasionally it will go in to limp mode or a check engine light will come on. I have a ScanGauge hooked up continuously and monitor several different parameters while I drive. I always clear the codes and usually disconnect the chassis battery with the disconnect switch to reset the ECM. In every case, this has corrected the problem and it may not show up again for several months or several thousand miles. I have had the O2 sensor code show up and it went away with a reset. I am still on my original O2 sensors and I am now approaching 90,000 miles. I basically chalk up an occasional check engine light or limp mode as being something temporary that probably tricked a sensor in to thinking there was a real problem. If there was a real problem, a reset would not work and it would quickly show the same code.Naturally you can replace the O2 sensors if it gives you peace of mind but that does not mean that another temporary problem may show up next time out.

It is hard to imagine the 02 sensors are bad at such a low mileage but it is possible to kill them. If someone used the wrong silicone sealant when replacing a part it will continue to contaminate the sensors. Of if there was ever a problem where antifreeze went through the combustion process (head gasket, etc.) it will also foul the sensors. It may even be possible for bad gas to coat them.You can save a small fortune by replacing them yourself. . They are very inexpensive (the last GM 02's I bought were about $23 at NAPA but that was a while back) and are no more difficult to change than a sparkplug (which is what they're made from).You don't want to push them for too many miles because your only hurting yourself. Long before they fail, they get lazy and don't respond quickly to fuel mixture changes - they don't trip the light until they are very bad although some models trip the light at specific mileages regardless of performance. Fuel efficiency diminishes as well.Personally, I would go ahead and change them myself. Rgatijnet, At 90K you wont believe the performance difference you'll feel with fresh sensors.Happy humbug!Scott

I had the exact same problem with my 2004 8.1 engine. I replaced the sensors myself and the problem continued. I cleaned the MAF and the problem cleared right away and my power increased. So have them clean the Mass Air Flow Sensor.

P0202 is NOT an O2 sensor code. Sure that's what they found?

tderonne wrote:P0202 is NOT an O2 sensor code. Sure that's what they found?Was thinking the same, that will be injector issues...

GM 8.1 Workhorse O2 Sensors | Good Sam Community

rgatijnet1
Explorer III
Dec 24, 2016
I have the same 8.1L engine and occasionally it will go in to limp mode or a check engine light will come on. I have a ScanGauge hooked up continuously and monitor several different parameters while I drive. I always clear the codes and usually disconnect the chassis battery with the disconnect switch to reset the ECM. In every case, this has corrected the problem and it may not show up again for several months or several thousand miles.
I have had the O2 sensor code show up and it went away with a reset. I am still on my original O2 sensors and I am now approaching 90,000 miles.
I basically chalk up an occasional check engine light or limp mode as being something temporary that probably tricked a sensor in to thinking there was a real problem. If there was a real problem, a reset would not work and it would quickly show the same code.
Naturally you can replace the O2 sensors if it gives you peace of mind but that does not mean that another temporary problem may show up next time out.
ScottG
Nomad
Dec 24, 2016
It is hard to imagine the 02 sensors are bad at such a low mileage but it is possible to kill them. If someone used the wrong silicone sealant when replacing a part it will continue to contaminate the sensors. Of if there was ever a problem where antifreeze went through the combustion process (head gasket, etc.) it will also foul the sensors. It may even be possible for bad gas to coat them.
You can save a small fortune by replacing them yourself. . They are very inexpensive (the last GM 02's I bought were about $23 at NAPA but that was a while back) and are no more difficult to change than a sparkplug (which is what they're made from).You don't want to push them for too many miles because your only hurting yourself. Long before they fail, they get lazy and don't respond quickly to fuel mixture changes - they don't trip the light until they are very bad although some models trip the light at specific mileages regardless of performance. Fuel efficiency diminishes as well.
Personally, I would go ahead and change them myself.

Rgatijnet, At 90K you wont believe the performance difference you'll feel with fresh sensors.

Happy humbug!
Scott
ArchHoagland
Explorer
Dec 24, 2016
I had the exact same problem with my 2004 8.1 engine. I replaced the sensors myself and the problem continued.

I cleaned the MAF and the problem cleared right away and my power increased.

So have them clean the Mass Air Flow Sensor.
tderonne
Explorer
Dec 24, 2016
P0202 is NOT an O2 sensor code. Sure that's what they found?
MudChucker
Explorer
Dec 25, 2016
tderonne wrote:
P0202 is NOT an O2 sensor code. Sure that's what they found?

Was thinking the same, that will be injector issues...
ArchHoagland
Explorer
Dec 25, 2016
Mine were P0151 and P0131 codes. I noticed kcgaz said code 202 but I thought maybe he was confused.

In any case the O2 sensor is doing it's job of reporting a problem with the air/fuel mixture and it's burning.
kcgaz
Explorer
Dec 25, 2016
Thanks for all of the great input. I thought the service guy said 202, I will check when I call Monday. I was not aware of the limp mode, anything else that I need to be aware of with this engine? My past RV's have been Ford products.
MudChucker
Explorer
Dec 25, 2016
Strange, some how I pocket posted several hours later...
ArchHoagland
Explorer
Dec 25, 2016
kcgaz...I'd suggest new plugs and wires based on my experience over the past 80,000 miles and 12 years.

Another thing to be aware of is the transmission, Allison 1000, came with Dexron iii in it.

That needs to be changed every 2 years or 24,000 miles along with the spin-on filter.

I suggest switching to Transynd that is the recommended synthetic fluid now.
Coffee_Grinder
Explorer
Dec 25, 2016
Would like an opinion of diesel vs gas on class A homes. Not familiar with diesels at all but believe they are more expensive to maintain