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Tested my 80 today and finally got it to pass on NOx but now the CO is high, been using 100% pure ethanol free gasoline.
Passed CO last time but now at 33.3923, 20 is max. I know that getting new O2's and or Cats will get me to pass but no funds to do so at this time.
Passed CO last time but now at 33.3923, 20 is max. I know that getting new O2's and or Cats will get me to pass but no funds to do so at this time.
Another failure here today too. Vast improvement from 29.xxx CO down to 18.3501, limit is 15.
- Thread starter
- #44
Well, I was feeling hopeful. All for not.
Changed the oil to 10w30 Mobile 1, filled up with 88 octane ethanol free gas, put ~70 miles on her and BOMBED latest test. Failing HC now too...
HC - 2.9134 (2.5000 max)
CO - 97.5629 (25.0000 max)
CO2 - 674.9241
NOx - 1.9010 (4.5000 max)
Pretty livid, but even more defeated at this point. Will test the EGR at some point this weekend, maybe. The cats are pretty old and have been replaced at some point I am assuming as they are welded in and everything I have seen suggests that they were bolt-in from the factory.
Have only had her since late December, but she is running the best I have seen. Better than any thing that I test drove prior to the purchase.
Would replacing the cats be a sure-fire pass? At this point I just want to get it plated and move on.
Changed the oil to 10w30 Mobile 1, filled up with 88 octane ethanol free gas, put ~70 miles on her and BOMBED latest test. Failing HC now too...
HC - 2.9134 (2.5000 max)
CO - 97.5629 (25.0000 max)
CO2 - 674.9241
NOx - 1.9010 (4.5000 max)
Pretty livid, but even more defeated at this point. Will test the EGR at some point this weekend, maybe. The cats are pretty old and have been replaced at some point I am assuming as they are welded in and everything I have seen suggests that they were bolt-in from the factory.
Have only had her since late December, but she is running the best I have seen. Better than any thing that I test drove prior to the purchase.
Would replacing the cats be a sure-fire pass? At this point I just want to get it plated and move on.
Don't know how true it is but some say that there is an additive in motor oil used as an preservative that will increase emissions till it burns off.
Here are some of my tests:
with E10 gasoline and Delo 400 syn motor oil
HC 0.8458 2 max
CO 21.5061 20 max FAIL
CO2 774.7346
NOx 4.5651 4 max FAIL
with E10 and my canola oil motor oil mix in the crank case.
HC 0.8449 2 max
CO 13.6570 20 max
CO2 691.0228
NOx 4.2559 4.0 max FAIL
with 100% gasoline and Valvoline High Mileage semi syn motor oil
HC 1.243 2 max
CO 33.39323 20 max FAIL
CO2 569.0722
NOx 3.8088 4 max
Here are some of my tests:
with E10 gasoline and Delo 400 syn motor oil
HC 0.8458 2 max
CO 21.5061 20 max FAIL
CO2 774.7346
NOx 4.5651 4 max FAIL
with E10 and my canola oil motor oil mix in the crank case.
HC 0.8449 2 max
CO 13.6570 20 max
CO2 691.0228
NOx 4.2559 4.0 max FAIL
with 100% gasoline and Valvoline High Mileage semi syn motor oil
HC 1.243 2 max
CO 33.39323 20 max FAIL
CO2 569.0722
NOx 3.8088 4 max
- Thread starter
- #46
After seeing this thread this morning, and looking this link from said thread I went out and cut open the cover on the VAF. Marked where it currently was and moved it 2 notches "tighter" or leaner. It still does not go fully closed when the engine is off, but I did not want to go too lean. Drove her up 25 to the Loveland Park and Ride exit and turned around. Went straight to the emissions check on Marshall (Wads) and 52nd.
BOOM, she passed! With flying colors, IMO.
HC - 0.8802 (2.5000 max)
CO - 10.1139 (25.0000 max)
CO2 - 780.1108
NOx - 2.3943 (4.5000 max)
It makes sense, now the spring in the VAF is going to weaken over time. I had noticed that I had to force mine to fully closed to do the test in the FSM. While I had the cover off I also noticed that when the meter / gate is fully closed it opens a circuit open.
Also noticed that it appeared that someone had been in there before.
It would make sense to me that the higher mileage 93/94's would need this even more. I just rolled 175k yesterday. So yours @landtoy80 would probably need even more adjusting possibly. Mine just barely holds that circuit open when the engine is off. I am guessing I could go another notch leaner, but I am going to leave it for now.
BOOM, she passed! With flying colors, IMO.
HC - 0.8802 (2.5000 max)
CO - 10.1139 (25.0000 max)
CO2 - 780.1108
NOx - 2.3943 (4.5000 max)
It makes sense, now the spring in the VAF is going to weaken over time. I had noticed that I had to force mine to fully closed to do the test in the FSM. While I had the cover off I also noticed that when the meter / gate is fully closed it opens a circuit open.
Also noticed that it appeared that someone had been in there before.
It would make sense to me that the higher mileage 93/94's would need this even more. I just rolled 175k yesterday. So yours @landtoy80 would probably need even more adjusting possibly. Mine just barely holds that circuit open when the engine is off. I am guessing I could go another notch leaner, but I am going to leave it for now.
WOW. I will give it a try.
Did you still have ethanol free gas in the tank?
Would it be wise to adjust and leave it that way or set it back after test?
I have for years said the exhaust smells rich.
From my reading a lean condition will increase NOx. I hope leaning the fuel mixture doesn't raise my NOx, guess I should keep ethanol free gas in it to keep the NOx down.
Did you still have ethanol free gas in the tank?
Would it be wise to adjust and leave it that way or set it back after test?
I have for years said the exhaust smells rich.
From my reading a lean condition will increase NOx. I hope leaning the fuel mixture doesn't raise my NOx, guess I should keep ethanol free gas in it to keep the NOx down.
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- Thread starter
- #48
I did still have the 88 octane ethanol free fuel in the tank. I think it would have still passed without it though.
I am going to leave mine where it is. My NOx is right around where it has been all along. Also, if/when you cut your VAF open, look at the switch when the meter is fully closed. I am willing to bet yours is way off from opening the circuit (whatever it does I do not know).
Here are my NOx readings from when I first started my emissions saga, oldest to newest, with newest being the passing one.
1.9088
2.1617
2.0799
1.9880
1.9010
2.3943
I opened mine and the spring is tight and door flap closes tightly. The little switch was in contact/open circuit. It would open the circuit and close the circuit when opening and closing the flapper door. No sign of wear or corrosion.
Unless turning the gear wheel changes the signal, tightening the spring will not help me out.
I turned mine two notches and will emissions test next week.
Unless turning the gear wheel changes the signal, tightening the spring will not help me out.
I turned mine two notches and will emissions test next week.
Tested after adjusting the VAF.
HC 0.9941 2 max
CO 20.9723 20 max FAIL
CO2 693.9485
NOx 4.4171 4 max FAIL
It lowered CO and HC but raised NOx.
I do now have 2000 mi on the oil and should change it and retest.
My best test was with E10 and my canola oil motor oil mix in the crank case.
HC 0.8449 2 max
CO 13.6570 20 max
CO2 691.0228
NOx 4.2559 4.0 max FAIL
I will make up some more canola motor oil and see how it does with the VAF adjustment and E0 gasoline.
HC 0.9941 2 max
CO 20.9723 20 max FAIL
CO2 693.9485
NOx 4.4171 4 max FAIL
It lowered CO and HC but raised NOx.
I do now have 2000 mi on the oil and should change it and retest.
My best test was with E10 and my canola oil motor oil mix in the crank case.
HC 0.8449 2 max
CO 13.6570 20 max
CO2 691.0228
NOx 4.2559 4.0 max FAIL
I will make up some more canola motor oil and see how it does with the VAF adjustment and E0 gasoline.
After seeing this thread this morning, and looking this link from said thread I went out and cut open the cover on the VAF. Marked where it currently was and moved it 2 notches "tighter" or leaner. It still does not go fully closed when the engine is off, but I did not want to go too lean. Drove her up 25 to the Loveland Park and Ride exit and turned around. Went straight to the emissions check on Marshall (Wads) and 52nd.
BOOM, she passed! With flying colors, IMO.
HC - 0.8802 (2.5000 max)
CO - 10.1139 (25.0000 max)
CO2 - 780.1108
NOx - 2.3943 (4.5000 max)
It makes sense, now the spring in the VAF is going to weaken over time. I had noticed that I had to force mine to fully closed to do the test in the FSM. While I had the cover off I also noticed that when the meter / gate is fully closed it opens a circuit open.
Also noticed that it appeared that someone had been in there before.
It would make sense to me that the higher mileage 93/94's would need this even more. I just rolled 175k yesterday. So yours @landtoy80 would probably need even more adjusting possibly. Mine just barely holds that circuit open when the engine is off. I am guessing I could go another notch leaner, but I am going to leave it for now.
This is really interesting. I have been saying for years my 94 smells WAY rich. It is at 241k. Plugs always look pretty good and I have had a random code 26 Rich code forever that comes and goes. I am going to try this tomorrow. I have a question though. In your pic I looks like you rotated counter clockwise but in the pic of the link you posted it shows that leaning out would be turning it clockwise. Am I seeing something wrong ? Looks like I just pop up the little lever on the teeth and rotate it to the right to lean it up a bit ?
- Thread starter
- #53
The little scratch in the "dial" is my original marker. In effect, making the spring "tighter" and fully closing the VAF gate when the engine is off. I am not sure what the blue mark is, like I said it looks like someone has been in there before. I did not get any service history when I purchased her. So your guess is as good as mine!
ah ok. I see that no. My eyes were going right to the blue mark. I am going to try this out tomorrow. Thanks
I saw the same blue mark and got confuseted. Then I saw the little mark.
I made a mark and took before and after pic but the after pic failed, you can kinda see it.
I made a mark and took before and after pic but the after pic failed, you can kinda see it.
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Tested again with my Canola oil and numbers got worse. They went down last time. The driver door handle broke off at the emissions station. today. I have one more free retry, I will try it Saturday morning to see if the morning moisture helps.
HC 1.0356 2 max
CO 27.9096 20 max
CO2 644.8515
NOx 4.2120 2 max
HC 1.0356 2 max
CO 27.9096 20 max
CO2 644.8515
NOx 4.2120 2 max
Last straw. Selling the 80. Driver door handle broke at the emission test station.
I will miss it but it needs to go.
I will miss it but it needs to go.
It sold,
update. So I opened up my air meter the other day. I tightened the spring one tooth. Barely noticed anything. Went one tooth at a time until i got to 3. Drove around for about an hour and it start feeling less smooth on acceleration. Then after about 10 miles cruising around I was accelerating really softly (like barely on the gas under load) and it started pinging. My timing is currently set at stock 3 degrees because when I got the truck it was pinging bad and previous owner had it set at 7 degrees. For some reason I have never been able to add timing to this thing.So I adjusted my TPS which was slightly off since last time I did it about 6 months ago. Made it run a tad better with less ping. Then I decided to loosen the spring tension one notch looser than stock and it runs WAY smooth now and not knocking. So loosen the spring tension one tooth and clocked the tps slightly to right to bring back into spec and it seems to super smooth, holds idle perfectly and acceleration seems a lot stronger.
