No Service Engine Light - Not Passing Smog

[2ndwindranch]

I am continuing this conversation as a new post. Once we found our OBD2 connector (per thread diagnostic plug location) now we're getting 0 codes, like all is well. All is NOT well. I've just finished searching through these forums for similar "service engine" lights and came across a thread that talks about a bad ECM? If I'm a techie person, is this something I can fix or take a look at?

I also saw something for emission warranty for coaches, how do I find out if we're covered under an emission warranty. We purchased this RV in Oregon from a dealership that is now out of business (we also had to take them to court for not handling the registration portion of our deal properly).. anyway, we're now in California.

We're just trying to take the next steps to figure out what is wrong, and though we could just plug in our OBD2 device and all would be solved... NOT!

[Fred and Bonnie]

Start at http://www.arb.ca.gov/msprog/warranty.pdf for info on California emission warranties.

What part of the test did your unit fail?

Check your local WCC service center to verify they are qualified to troubleshoot the emission system, you may have to use another service.

fred

[Duner]

Quote:

Originally Posted by 2ndwindranch ....... If I'm a techie person, is this something I can fix or take a look at?

My 1st motorhome, a Ford V10, failed the CA smog and I found one of the two O2 sensors had failed physically. I think it's a common problem to have an O2 sensor failure. You can do a resistance test to check them. Compare the two and see if one is off. Not sure what ohms they should be, somebody on the forum may know. At least it's an easy thing to eliminate.

[DAN L]

Quote:

Originally Posted by 2ndwindranch I am continuing this conversation as a new post. Once we found our OBD2 connector (per thread diagnostic plug location) now we're getting 0 codes, like all is well. All is NOT well. I've just finished searching through these forums for similar "service engine" lights and came across a thread that talks about a bad ECM? If I'm a techie person, is this something I can fix or take a look at? I also saw something for emission warranty for coaches, how do I find out if we're covered under an emission warranty. We purchased this RV in Oregon from a dealership that is now out of business (we also had to take them to court for not handling the registration portion of our deal properly).. anyway, we're now in California. We're just trying to take the next steps to figure out what is wrong, and though we could just plug in our OBD2 device and all would be solved... NOT!

please add your rv info to your signature profile.

ifirc your rv is too old, 454?, for any kind of warranty. the ecm is the engine control computer. it is kinda drastic to just replace it without any good reason. if you want to throw parts at it, imho oxygen sensors would be a good bet.
it is possible that you erased the codes when the code reader was plugged in to the obdll plug. you gotta follow the instructions to get a good reading.
on my machines with my code reader, one plugs in the code reader, turns the ignition switch on (do not start) and then ask the code reader to read. after reading it should show codes or state that their are 0 codes. it is possible to erase codes inadvertently when trying to read them.

[2ndwindranch]

Quote:

Originally Posted by DAN L please add your rv info to your signature profile.

Thanks Dan, I added RV info to profile this AM!

Yes, it is a 454 and I've been thinking O2 sensors all along. I think at this point we're just going to take it to the WH dealer about an hour away for them to take a look at it (they're the ones who found the plug!). Anyway, the issue with us fixing it is a friend of ours is a mechanic and he and my husband have a barter so it's in our financial interest to let him fix it so we may have the dealership do the estimate and pay them for their time to troubleshoot, but who knows. This whole thing took a wrong turn on us.

[2ndwindranch]

Fred, the unit is failing high hydrocarbons. There is no service engine light. Our OBD2 unit has no information or no stored information as if the onboard computer has no data. What's weird, is that after I drove this for 2 hours taking it to and from the Workhorse service center an hour away, you'd think it would have triggered a fault. The OBD2 cannot even retrieve a VIN like it appears it should?

[dieselclacker]

Just my opinion, but your idea of taking your coach to a COMPETENT Workhorse service center seem like a good one. Save the barter with your mechanic friend for another occassion.

Dieselclacker

[DriVer]

Quote:

Originally Posted by 2ndwindranch All is NOT well. I've just finished searching through these forums for similar "service engine" lights and came across a thread that talks about a bad ECM? If I'm a techie person, is this something I can fix or take a look at?

2ndwindranch, When an SES lamp is set, it is typically related to an emission control device. You may or may not get a DTC on your scanner however that said if your machine is scanned using a Tech II scanner at a WCC or GM dealer, they should be able to determine "What's up!"

Quote:

I also saw something for emission warranty for coaches, how do I find out if we're covered under an emission warranty.

What is your year, make and model again? Perhaps you can place this info in your signature file. Chassis type? If you are a Chevrolet, I don't expect that you are still covered under the extended emission control warranty.

[2ndwindranch]

Quote:

Originally Posted by DriVer What is your year, make and model again?

It is a Chevy 454... 2000 Winnebago Brave Workhorse Chassis. (I need to fix my sig... just noticed I have it as an '01)

As an update this AM, I just plugged the scanner into 2 other vehicles, all get the same reading no DTC codes present. That seems normal, those 2 cars are running fine, but I was hoping there would be some sort of historical DTC codes present.

I am using a INNOVA 3100e CanOBD2 Diagnostic Tool. I have opened a tech support ticket with them for assistance on making sure I am reading everything right. I know for sure we have no inadvertantly erased any data as that button is red and even gives an are you sure warning

There's really nothing we can do until Tuesday and we have all weekend to just stare at this thing in our driveway so you'll have to pardon my several posts because we just aren't that patient.

[bigskymt]

Harbor Freight sells a laser thermometer for $40. A catalytic converter needs to reach about 600F to work and up to 1200F. If its not reaching that temp your emisions will be high.
02 sensor failure will give you a check engine/service engine and a code.

[2ndwindranch]

Ok, do to clarify, if the O2 sensors are bad, I would have a service engine light, correct? We do not.

If its the catalytic converter, there would be no service light, correct?

We are still planning in taking it in, and at this point using our obd2 tool on our other cars to make sure were reading this correctly.

What's weird is the scanner does not pull the vin no. From the RV.

[Topflite51]

Quote:

Originally Posted by 2ndwindranch Ok, do to clarify, if the O2 sensors are bad, I would have a service engine light, correct? We do not. If its the catalytic converter, there would be no service light, correct? We are still planning in taking it in, and at this point using our obd2 tool on our other cars to make sure were reading this correctly. What's weird is the scanner does not pull the vin no. From the RV.

I have seen very few bad O2 sensors, that activate the service engine light.

Generally speaking, if the converter was bad you would have failed other parts of the emissions test.

[bluepill]

I believe that CA has "smog shops" that specialize in emissions problems. If you want to test the O2 sensors and catalyst efficiency yourself it is quite easy. You just need a voltmeter (Walmart or Radio Shack under $20).

Tap into the sensor lead - not the heater or ground - of each O2 sensor and observe the voltage swings. I won't get into details, but you can Google all the info you need in less than an hour.

[2ndwindranch]

Update on today progress since earlier post... bought heat gun at harbor freight, am sitting in the RV now getting things nice and hot. We have 2 converters almost in top of each other, the upper one got to 450, the lower one got to 180. The engine wad running for about 15 min, rev'd at 2500 rpm and engine reached 110 normal for us driving temp. As a side note, were trying no generate a service engine light by removing the gas cap, didn't happen this round, nut I'm aware that takes time.

We will do the voltometer test now, the obd2 did explain the amps change there, so I will review that explanation.

THX! Stay tuned for more!

PS: what us up with both converters not reaching 600? Is it because there are 2, so the 2 temps combined ate around 600... or is that our issue?