Super Duty Smog Solutions to Help You Pass Your Test
Has a mere warning light caused you to fail a smog test in your Super Duty, even if it has nothing to do with smog?
Living in a place like California has its perks, obviously. Lots of sunshine, mostly dry weather, and excellent driving roads make it a truck lover’s paradise. Until you head out to get your truck smog certified, of course. Because Cali has some seriously strict rules that, in many cases, can quickly pump the brakes on your modding fun. Ford Truck Enthusiasts member jtybt ran into this very problem recently with his Super Duty. And it wasn’t even caused by a performance enhancing mod.
“Dang California. I originally followed Chris’ excellent thread regarding airbag steering wheel removal so it wouldn’t squish my toy schnauzers if it went off. Anyway, CA changed their smog tests for diesels and I’m getting a cruise control off signal. What that has to do with smog is anybody’s guess, especially since it never had cruise control.
I just replaced the airbag, following Chris’ thread again. But I’m getting a flashing airbag signal. When the airbag was out, I had a straight seat belt light. I suspect it’s my seat belt tensioner since I replaced the Ford seats with GM ‘swivel’ seats and they’re not connected. My question is, is there anyway to bypass the whole cruise control wiring system?”
Seems pretty silly, but those are the breaks these days. Thankfully, KC8QVO has some answers. Along with a potential solution.
“I suspect if your vehicle’s OBDII system has any fault codes it won’t pass. Whether they are emissions related or not – as is yours in relation to cruise. It isn’t that cruise has anything to do with smog, it is that your OBDII is reading a fault.
As to bypassing the signal, no idea on that one. You may get a copy of the Haynes repair manual to start with. This will have electrical schematics in it. Perhaps some not as detailed and without the parts keys, but the outline of the main circuits may help you. You may also want to consult your local Ford dealership. They may be able to assist further.
If you don’t already have a code reader I suggest getting one. I use a ScanGauge II. It is a wonderful device. There are a lot of other options out there.”
All of that at least makes this Super Duty issue a little more reasonable. But as brian42 points out, things aren’t getting any easier for owners of older vehicles like these.
“Smog shops are getting smarter on the older vehicles. I failed this year for a part I installed 5 years ago that the shop told me was okay. And it passed the last two inspections.
I’ve always had the OBD II check as that connects directly with the state (can’t cheat). My visual inspection has gone from a 5 minute walk around to this time it was a 20 minute inspection. It’s getting harder to get things by them nowadays. And even harder to find a friendly shop. At least in my area, that’s the way it’s going.
Anything that sets off the SES light is a fail, emissions-related or not. Since the 7.3L is not a fully compliant OBD II system, some of the codes do not set off the SES light. These are soft codes (e.g. AIH, EBPV) that are not picked up on generic OBD II software so you won’t fail for those.”
For older Super Duty owners in California, that’s not exactly promising news. But we want to hear from you about your personal experiences (and potential fixes) with this problem. Head over here and let us know how if you’ve managed to circumvent this issue and pass a smog test!