That's a Roger my friend will do. Now Do I have to drive X many miles at X MPH to reset it?

 

It will reset very quickly. I wouldn't worry about it.

 

Thanks for your help.....now I have to find a zip tie for my TPS plug because the clip that locks it into place is broken and I'm having some stumbling issues on cold starts and now it's starting to do it on warm starts. The IAC valave is opening up to keep it from stalling.

 

Ok, here's a different twist to this question.

Is there any way to get the PCM to readjust faster after it gets reset? It seems like it takes mine as much as 2 tanks of fuel sometimes before its performance becomes consistent. Before it has readjusted itself, the truck seems like it performs very differently each time I drive it. One time going for a drive it will seem to have extra pep and sensitive throttle response, then the next time I start it and go for a drive it seems to be less peppy and more sluggish than the last time. Shifts seem to happen at different rpms and different throttle positions, etc. until finally after as much as a couple of tank fulls of gas, the performance becomes consistent. Anybody else experience these conditions to this extent, or am I the only one?

 

I'm pretty sure it does clear any stored codes and CEL's, but I could be wrong. You don't need to do it for an air filter change unless you want to, but an air filter isn't going to make any performance difference. I would do it after install of any performance part like bored out TB, heads or rockers, cam, etc..., and after any tune-ups. You actually don't need to do it at all, it will eventually learn whatever it is you have put in. It's just more proactive this way.

The downside of doing it is that you will see a decline in your gas mileage for a little while. When the PCM is reset, it runs rich for some time. More in the beginning, then less as time goes on until it has everything dialed in.

 

Dude you hit it right on the head. Mine does that but I haven't reset my PCM yet. But you are dead on. I haven't the foggiest idea of whats going on either.

 

Hey Silver I know this is kinda off topic but I notice you're running a Flowmaster Super 40 and a Magna Flow Cat, how's that working out for you? That's what I'm in the market for. Currently I have the original cat and a 5 ft section of 3" straight pipe that has split duals out back.

 

Welcome to speed density design. I notice mine takes anywhere from 200-400 miles before I feel like it is were it needs to be. On a mass air system, it seems like it happens a lot faster.

 

What's the difference between and speed density design engine nd a mass air? Also look at my previous response regarding you exhaust system.......unless you no longer have it.

 

It's complex when you start looking at open loop operations versus closed loop, but in a nut shell, speed density engines have no way to accurately measure the amount of incoming air into the cylinders. Speed density engines use a combination of readings from different sensors (namely o2) to give the PCM an idea of how much air is present. But it takes time because the algorithms used in the PCM require data collection over a period of time to so that it has confidence in the readings it is seeing. It is also not able to make changes that quickly either.
More modern Mass Air Flow (MAF/AFM) engines use a mass air sensor to give the computer that information real time, and it can therefore make changes to fuel and timing much quicker based on that information.