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Discussion Starter #1
Figured I'd post here, in case anyone else has had a similar problem....my hydrocarbons are running around 566 at idle, and should be under 115...this confirms what I thought, it's running way too rich...

However my o2 (oxygen) is reading 1.9 at idle and should be closer to 0.

What I suspect is I could have 2 problems

1. In order for the cat to work, oxygen should be close to 0....with oxygen at 2%, I suspect that the cat is dying....

2. I'm running rich, real rich. 9-10 mpg's average....lower than what I should be doing in a 5.0. (also smells extremely rich) I was thinking o2 sensor, but it "looks" fairly new (def a bosche o2 sensor)...any of you know how to test this 4 wire o2 sensor??

Any other ideas from your experiences?? I'm not as worried about being able to pass smog now, as I am getting the run-rich problem to go away...as I know I have a few more mpg's I can pick up. I've got to get my hydrocarbons down quite a bit.
 

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You should have come across this thread by FSB member Sixlitre - I done failed my smog test (tears) where it would have shown you how to go about PASSING 100% a Cali smog test assuming your BKO has no serious mechanical problems.

So:
New spark plugs
New O2 sensor if approaching or at 30K miles, preferably Denso/ Motorcraft instead of Bosch, as they tend to run richer by design....recent FSB thread etc. AND disconnect the O2 plug from the harness, DON"T shortcut and just cut the wiring and crimp on the new one because you want the best continuity for voltage so it's functioning optimum.
Oil/filter change if approaching 3K miles
Back down timing from OEM 10* BTDC to approx 8* BTDC (BTDC = before top dead center) check and make sure you can read your harmonic balancer and the timing marker is clean, paint both silver if necessary.
Drive the vehicle 1 hour prior in order to heat up the engine and CAT/S etc.
Add 2 x 32 oz. bottles = 1/2 gallon of 91% Isopropyl Rubbing Alcohol ($5.-6.00 in any Drugstore, Grocery Pharmacy) to 1/4 tank of gasoline in a discrete location right before you drive in to test, the alcohol creates mositure when mixed with gasoline reducing HC and CO% numbers dramatically as well as all the other numbers across the board.
Make sure you have the correct/approved "gas cap" on, they don't like key/locking gas caps.
Make sure all somg equipment is on and working efficiently, especially for a visual inspection.otherwise you will FAIL.
* BEWARE of smog technicians ASKING YOU ANY QUESTIONS regarding the length of time or distance it took you to get to the smog facility, whether you work on the vehicle yourself or made mechanical changes, just anything out of the ordinary PLAY DUMB, I DON'T KNOW, I DON'T WORK ON THE VEHICLE ETC. ETC. ETC.

I have now sucessfully PASSED to bi-annual smog tests here in Socal, 2009 and recently Sept. 2011 passing with flying colors.......there are also several smog passing products available like "Guaranteed To Pass" and "Heet" sold in most auto parts stores......Guaranteed to Pass is worthless IMO, back in 2007I used it and failed 1st time out and I didn't get the refund as they had advertised....can't speak for Heet but I'm sure it won't fair much better, the alcohol works tried, true and tested.


Good Luck ~ :thumbup
 

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Figured I'd post here, in case anyone else has had a similar problem....my hydrocarbons are running around 566 at idle, and should be under 115...this confirms what I thought, it's running way too rich...

However my o2 (oxygen) is reading 1.9 at idle and should be closer to 0.

What I suspect is I could have 2 problems

1. In order for the cat to work, oxygen should be close to 0....with oxygen at 2%, I suspect that the cat is dying....

2. I'm running rich, real rich. 9-10 mpg's average....lower than what I should be doing in a 5.0. (also smells extremely rich) I was thinking o2 sensor, but it "looks" fairly new (def a bosche o2 sensor)...any of you know how to test this 4 wire o2 sensor??

Any other ideas from your experiences?? I'm not as worried about being able to pass smog now, as I am getting the run-rich problem to go away...as I know I have a few more mpg's I can pick up. I've got to get my hydrocarbons down quite a bit.
And, why have you eliminated bad cats as the potential problem?
 

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Discussion Starter #4
that's fantastic information, thanks!!!
The high HC isn't a function of the cats...that's a function of the engine running rich. I don't seem to have a vacuum leak, so it's not introducing air into the system and richening out....It's "got" to be the 02 sensor why it's running rich.

My cat could be marginal, hence the high o2 reading....that's something that I may be able to get to pass by driving the piss out of it and warming it up. If it still doesn't pass, I'll cut both of them out and put in one 3 way hi flow cat (not exactly legal, but oh well right?)...or keep them both and just replace the faulty one. I'll also be trying all the results above...My timing is at 14 degrees, which will bump up hc's a little..so I'll back off on that.
I'll post up my results as I work on it over the next couple of days.
 

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Discussion Starter #6
I dont kow why you didnt just call me Jeremy? My cars never fail, ever!
haha...thanks man! I'm in the same boat, however I'm wanting to fix this thing soley because of gas mileage...putting 16 gallons in and getting 150 highway miles off that is bullshit...now I don't mind crap mileage, but in the case of this truck, I should get at least low teens, so that's my goal, and tweaking this truck to pass smog will greatly help bring my mpg's to where they should be. If I can get my MPG's to mid teens where it should be at, then that may help my decision to step up to 35's eventually.
 

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Don't forget the 91% Isopropyl Rubbing Alcohol for the Smog test...............it's a winner every time.

Good Luck ~ :thumbup
 

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I was thinking o2 sensor, but it "looks" fairly new (def a bosche o2 sensor)...any of you know how to test this 4 wire o2 sensor??
In my opinion, if you were thinking 02 sensor, you were right. I'd take that Bosch sensor to the shiznit can, and replace it with a Motorcraft. Bosch, and Ford don't mix. Mine is a 2 wire sensor, IIRC, Motorcraft.
 

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Discussion Starter #9
swapped out the old 4 wire o2 for a used 3 wire mustang o2 I had laying around...this made an instant difference and I could tell it was running much leaner

backed the timing down to 9 degrees, had a 1/4 tank of gas and dropped in two 32 ounce bottles of that alcohol.

The o2 sensor made the biggest difference...it dropped my hc's down about 70%....not still within passing limits, but almost...it tells me a brand new 4 wire sensor will do the trick...

however my 02 and co2 is way off...the rear cat is faulty....

20 minutes after dumping that alcohol in, it ran so f'ing back I barely got it out of the parking lot...

I had to go to the gas station and put 6 gallons of gas in, which brought me above gas tank and it's still missing like a f'ckr

my .02?? Stay away from the alcohol, or use a very limited amount of it...it's not going to work anyhow, unless your vehicle is very marginal...then it would possibly do the trick to sway you over.. even so, the limits are so tight now (they were just reduced) that the smog tech said I'd likely never be able to get it to within passing range anyhow no matter what I do
 
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