semlin
curmudgeon
OK, so I finally got around to working on my EGR system this weekend. With much assistance and coffee from Riley, I cleaned the throttle body/plenum, replaced the modulator and VSV for EGR, cleared all hoses, then went back and failed the provincial emissions test again.
Here are the before and after EGR repairs results (g/km)
substance max allowable before after average
HC 0.99 0.6756 0.6245 0.1655
CO 12.43 9.9628 9.0036 2.6518
NOX 1.55 5.3381 3.6388 1.4807
So not much change. I have failed NOX twice and I'm still way above the average passing 93 80 on the other two (although I passed). My NOX did come down 33% but that might be due to the fact I was running a 10% ethanol blend 94 octane gas this time (supposed to reduce NOX emissions)
Anyway, the emissions guy says with that high a result it must be the cats. He said don't waste time on the EGR. They see a lot of fails, and a lot of applications for exemptions where you have to detail repairs made to show $500 spent to get a free year.
I have no codes and have checked the DLC to make sure it functions. My 93 has no 02 sensor behind the cats.
So now I have a couple of choices. I can fix it or try and beat it. There is the "emissions pass" in a bottle option at the local auto places for $40. The local parts dealer said a litre of methyl hydrate in a quarter tank of gas will get you through, but you have to then fill the tank up right away. Does anyone know if this is bad for the engine?? I use that stuff as gas stablizer for my outboard fuel so I assume it can't be that bad?
To fix it likely means new cats. I'm going to start a separate thread asking about this.
Here are the before and after EGR repairs results (g/km)
substance max allowable before after average
HC 0.99 0.6756 0.6245 0.1655
CO 12.43 9.9628 9.0036 2.6518
NOX 1.55 5.3381 3.6388 1.4807
So not much change. I have failed NOX twice and I'm still way above the average passing 93 80 on the other two (although I passed). My NOX did come down 33% but that might be due to the fact I was running a 10% ethanol blend 94 octane gas this time (supposed to reduce NOX emissions)
Anyway, the emissions guy says with that high a result it must be the cats. He said don't waste time on the EGR. They see a lot of fails, and a lot of applications for exemptions where you have to detail repairs made to show $500 spent to get a free year.
I have no codes and have checked the DLC to make sure it functions. My 93 has no 02 sensor behind the cats.
So now I have a couple of choices. I can fix it or try and beat it. There is the "emissions pass" in a bottle option at the local auto places for $40. The local parts dealer said a litre of methyl hydrate in a quarter tank of gas will get you through, but you have to then fill the tank up right away. Does anyone know if this is bad for the engine?? I use that stuff as gas stablizer for my outboard fuel so I assume it can't be that bad?
To fix it likely means new cats. I'm going to start a separate thread asking about this.