What Octane? Reply #32 – December 28, 2011, 06:19:58 PM My car actually hit the same on both the 15 and 25mph dyno sniffer tests. It passed visual fine, because the egr was still there. The vacuum line controlling it broke making it not function. It also did better with the smog pump bypassed when it locked up on me then it did functioning. They still ran the test, but failed me when they notice the pulley seized and bypassed.After repairing my egr gas mileage stayed the same as before. I was averaging 25-27 freeway, and near 30mpg if I did 5 under(70mph). I also averaged 14-19 city, but generally about 16. 14 being worst average, and 19 being best while driving careful. Never could crack 19mpg city though.Emissions, in my opinion, are useless. 3 of 4 years I drove my car without a functioning egr. No differance in fuel or emissions. Best mileage I was getting was with the smog pump bypassed. Quote Selected
What Octane? Reply #34 – December 28, 2011, 08:22:39 PM Her you gohttp://www.foxtbirdcougarforums.com/showthread.php?11193-Failed-emissions-got-a-new-cat-convert-and-got-WORSE!!!&highlight=Right there, paid $800 for a new cat and smog pump, and emissions got worse. The problem ended up being two bad map sensors, two bad fuel pressure regulators, and one bad o2 sensor. Actually, the emissions didn't change after swapping everything, except the map sensor, but all of the other sensors were bad. What is a dynamic or active test?Until this year cars were ran from 15mph to 30mph on a loaded dyno with the sniffer hooked up. Starting this year, now it is a idle and 1500rpm stationary test. My 87 bird I junked in march, ran better emissions with the smog pump bypassed then when I fixed it a week later. The egr did not function the first three years I drove the car. 4th year I replaced the vacuum lines and fixed my egr. Emissions were actually slightly worse with functioning egr then the previous 3 years.I also put about 40k on that car between the 3rd and 4th year. Nothing changed emissions wise except the nox going up slightly. I do not have all the paper work anymore. I threw it away when I junked the car. Long story short, here is two examples where a working smog pump and egr raised emissions. I honestly do not believe they do anything for the car, as long as it is running correctly. The gas mileage is definately not effected, in my cars at least. I drove between 200 and 400 miles a day, 7 days a weeks. I was down right buttstuff about my mileage.I worked 50 miles away from my home, and drove an additional 10 miles for a car pool each way. Then I drove back, and then did pizza delivery 25 miles from my home and 50 to 100 miles a day on the job. I could tell everytime I filled up if my tire pressures changed, and remedy it and be right back where I was before. The smog pump seizing and being bypassed gave me 1-3mpg and the egr being repaired did nothing. Getting the smog pump working again got me down that same 1-3 mpg freeway.I am not trying to argue anything, I just think that there is more to this then either of us are seeing. Quote Selected
What Octane? Reply #39 – December 29, 2011, 06:45:26 AM Actually, that engine had either 297 or 397k on it. Never did figure out which. I rolled the odometer over 199k twice. A 30 year emissins tech is the person, after running codes, told me it was my cat. I ended up passing by hollowing out my new cat, and replacing the map sensor. The origonal map sensor failed, and the one I replaced it with was also badout of the box. I ruled out that code thinking it was just stuck in memory and was already replaced. Third one, swapped off of a good running car cleared everything up. Passed emissions fine the very next day, with a hollowed out cat and new map sensor. That car had quite a few issues. Not too many $110 police impounds that you can get 150k out of. To give you an idea of how screwed up that car was, and not well maintained, it still had 1985 motorcraft wires on it. I learned quite a bit from that car. What actually killed that car was they wanted me to have an ignition key on it. I guess its against the law to drive with a busted out ignition key. I swapped in a floor shift colum and added the colum shifter to it and theshifter ended up snapping off. So, how did a new cat make my emissions worse if there so good for the engine and emissions? I never claimed to be an emissions tech, or be an expert, I am just giving you my experiances. Overall, the more emissions componets functioning on every car I have had, theemissions got worse, not better. Just saying. The egr definately will not effect gas mileage, in my experiance, and hasn't helped me any with emissions either. Quote Selected
What Octane? Reply #40 – December 29, 2011, 06:59:03 AM Oh and tom, if you would like to replicate my test, you can do the same thing by pulling the vacuum line off of the map sensor. When I had my motor mounts go bad on my last tbird, it would pull the vacuum line off the intake. It would shoot black smoke out of the tail pipe and leave black soot on the ground. Quote Selected
What Octane? Reply #41 – December 29, 2011, 01:08:52 PM You never saw me say that there aren't times when running higher octane fuel isn't in your best interest Tom. If you modify your engine so that it will still make more power, even though the fuel you're running has to have higher octane to avoid detonation, the modification was well worth it. Definitelu run higher octane. If the Engineers who designed your engine tell you to run 91 octane in the car, I'd never recommend running a lower octane fuel than what they recommended. What I have been saying all along is it's possible to think you're improving power by doing something that's supposed to add power, but actually doesn't. A perfect example of this ia advancing your timing so much that you have to run higher octane fuel. When you do that, power levels don't increase. You gained power by bumping the timing, but you lost the same amount of power by having to run a less potent fuel. I can't make this any easier to understand Tom. I've already made it perfectly clear that I think that running a higher octane fuel is fine if the modification you did results in a power gain even though your now using higher octane fuel.Higher octane+engine mod that equals a net gain in power=GOODHigher octane+engine mod that equals less, or no net gain in power=BADHaving to run higher octane is not always bad. Quote Selected
What Octane? Reply #44 – December 30, 2011, 07:08:59 PM Well tom, I am not trying to pretend to be an expert, and true I am practically cutting teeth compared to you. My emissions issues from that link were basically the first trouble shooting I did to any car. I was 18 years old, and I'm not even 25 yet. I do not come from an automotive back ground, nor do I think I know everything. Almost everything I learned was from forums or first hand experiance. When you talk I listen, and look into it. But I can prove one out of two times I replaced a cat, and both times my emissions go worse. In my opinion, the egr will not positively effect emissions. I ran my last car hard and kept it running good. In a 12 hour day, I was driving it at least 6 hours a day. I can tell you which gas stations in my area were the last to use ethonal, based purely off of gas mileage. In my experiance at least, there isn't a doubt in my mind that I am right. Maybe my cat wasn't working at all on either of my last two cars, and maybe my egr was clogged on one of them. But on my thunder bird I swapped both my intake and egr to a h.o. unit, and I cleaned the out of it and made sure it functioned, after they failed me for a seized smog pump. The emissions were worse, not better. I don't have any other explaination, do you? Quote Selected
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