... I really appreciate the input from both of ya'll!
Emm yeah, I'm sorry I forgot to mention about the CEL being on constantly, my appologies. The law is not very strict about the cat converter but I would prefer being more envoirnment friendly, just personal preference. I have no idea about simulator's so wouldn't know, morever since I'm not into modifying for performance, I'm pretty new at this stuff... Like I said I keep learning more and more through the awesome forums.
Get new cats and put them back in where they belong, and replace any missing O2 sensors. Scan the ECM for codes (the CEL could potentially be something else), as well. Most likely if the cats were removed, the post-cat O2 sensors were simply removed as well, given they are likely installed in the tube immediately after the cat, and the replacement "test pipes" did not have O2 sensor bungs welded onto them.
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The only easy way you know of yes, but theres more than one computer programmer that knows how to make an ECM run an engine problem free with very few program changes.
In this case a simulator wouldnt be pointless if you programmed the ecm to do only what you wanted it to do.
All the sensors are doing is telling the ecm what they see so it can change the fuel rates according to its parameters so it doesnt run to lean or to rich. At sea level which is where this vehicle is operated parameters wont change much at all. Theres no worry of a rich fuel mixture overloading the cat since it doesnt exist.
I have "home made" operating systems for 2 of my trucks that are only used off-road, they were both custom designed by a friend that took less than an hour to tailor them from factory to custom including using water and alcohol injection on one of them. Both trucks have passed local emissions. So I know for a fact simulators arent "pointless" the engine can run without being in open loop and can still return decent mileage and power. Its all in what the ecm tells the various components to do. Besides just how did engines operate before modern electronic systems? Everybody seems to forget a combination of old and new systems can be incorporated on a vehicle and they still run correctly. Especially in a country where noone checks emissions and engine operating systems. Most of the changes made to vehicles modified in the U.S. concentrate on keeping the system from tatteling on you, when you dont have to worry about that its a lot easier to mod the system.
Sea level operation is irrelevant. The O2 sensors have nothing to do with content of intake air. They tell the ECM how much oxygen remains in the exhaust after combustion, and then again after being catalyzed in the converter, so that it may adjust fuel and ignition parameters to compensate for other factors, such as reduced efficiency over time, inefficient mixtures of fuel in the tank, etc…
I don't know what you mean exactly by "home made operating systems" but there is no way an entire operating system was written in less than an hour. Changing fuel and timing tables, sure. But that is a far cry from an operating system. I also don't know anything about those 2 trucks, such as what year they are, what ECMs are being used, etc… I didn't say it wasn't possible, I said it wasn't easy or simple. Sure there are plenty of things one can do. But the best thing one can do, is not make assumptions about what other people are doing, particularly in such unstable areas of the world, to their trucks, because of what you or your friends did to your own trucks.