Good morning! My new to me 99 F250 superduty is failing its opacity test, with a reading of 44%.

I have a few issues with this that I'd like your opinions on.

1.) It doesn't smoke at all that I can see in the drivers seat.
2.) It doesn't smoke at all standing by the tailpipe watching as my wife does a in your garage and watch version of a snap test
3.)At the test station, they made me attempt 5 times times 3 snaps each, so 15 times before they overrode their RPM sensor and had me do
it manually and give me a fail at 44%
4.) It's stock. Bone stock. It's never been chipped according to what I was told. It was owned by a landscaping comapny, so I doubt they'd chip their truck :-P

However:

1.) The oil needs to be changed, the air filter is filthy. Rock auto should be delivering air, oil, and fuel filters today and I have 5 gallons of
Rotella synthetic sitting on my bench waiting, all these things should help, but I'm wondering if the larger issue here is that
someone screwed the test up royally.

Thoughts? Advice?

 

A plugged air filter can definitely contribute to that problem.

 

Yes, totally agree.

But if I was at 44% opacity, wouldn't I be seeing smoke? That's awful high.

 

I don't know, to be honest. I've never lived in a state that required opacity testing, so I don't know what 44% would look like . . .

 

The last two times I tested, I finished at 2% opacity. 44% is high, but I believe the limit is 40% here in Washington state, so you're not too far off. As said above, I also think your air filter has much to do with it. Also, you may already know, but make sure everything is at full operating temperature. I know it takes at least 15 minutes of freeway driving to get mine fully up to temperature.

It's possible there was some operator error too, but I think if you get everything right on your end, you'll have no problem passing. As a final measure, if you continue to fail, you can add biodiesel to your tank. It burns cleaner, and might help as well. For what it's worth, both times I tested I had at least B80 in the tank.

 

The limit in Washington is indeed 40% (I'm in Spokane).

I'll do the tuneup stuff and retest and see where we're at, I just cannot believe 44% opacity wouldn't be visible. If I still fail the retest I'll top off with some biodiesel from somewhere.


Thanks.

 

My stock truck shows 1-2% opacity on the yearly test, under which they put the engine at max output/full load. 44% should be a black cloud. Did you watch the test and see what sort of smoke was coming out?

I asked about warming up my truck and the guy said, 'don't bother - it warms up very quickly on the dyno' - which given the load, would seem true.

 

I did, I can see the tailpipe in the mirror. The truck doesn't smoke at all, and didn't during the test.

 

Change the air filter and check any other maintenance items.

Take it to a different test station.

Make sure the truck is fully warmed up. And I mean completely warm. A 30 minute drive should do the trick.

Pass test.

Profit.

 

Update:

Thanks for all the advice. Second test Saturday AM = 2.8%

I did do a full Oil/Fuel filter/Air filter change, but still, clearly their equipment was on the fritz the first test.

 

Good to know, and glad you got it worked out. I am going to go with moron government worker/equipment on the fritz/ combination of the 2.

 

I have been emission testing locomotives for 13 years and 44% opacity is very visible. It is not a black cloud like some clowns like to lay down but it is obvious. By the way locomotive are limited to 40% for a max of 30 seconds and 20% steady state.

 

Yeah, the whole thing was an exercise in frustration for sure.