after having my superchip for about a year now, and after resetting the computer numerous times i have come to the conclusion its not the best idea to reset it. every time i reset it, there is about a 500 mile period where the truck runs rough, shuts off at redlights, has a jumpy idle, and generally runs rich as crap. i have heard that these computers automatically relearn themselves, so why does everybody say to reset the dang computer?

finally, i thought maybe it has something to do with the superchip, maybe because it has to program the peak fule curves and all that good stuff, that it takes longer.....sorta like that initial learning period when you first put the superchip in.........

so my question is...why reset the computer? if its gonna relearn anyways, why drive a truck that shuts off for 500 miles? i am about to reprogram my chip and install a granatelli MAS, so i need to know whether it is to my advantage to reset the computer when i put them on............

thanks in advance mike

 

Hi Bullitt

Why do you reset the pcm...numerous times? Do you have to flip chip?

Anyhow...yeah, that would bug me to. I have flipchip 87/91+oct..the only thing ive noticed is when i flip..(i do disconnect) a very slight hesitation on restart...a very slight rough idle for only a few seconds.(not a problem) Next restart..just like new.

That has to be from doing the disconnect...the reason i do that is its my understanding it clears the pcm...which allows the new program to load quicker...not completely..as rest comes in with mileage. This part...requires tech. answer for some one else.

You can just flip, fill up, drive away...no disconnect...thats just the way ive always done it.

So far nothing like your problem...but i hardly ever flip anymore..My 4.6L likes that 91+ (higher when i can get it)

Good luck...OT

 

Hi Bullitt,

I couldn't agree more, certain situations excepted.

We'll always do a reset after doing a program change of course, so it takes efect as quickly as possible. But as far as just clearing the ECU just to clear it, or even clearing it when we get to the track, like with our Lightning, we generally don't do that. We don't clear the ECU unless we're doing mileage testing, and then will clear it each time we change brands, or if we install a new part, etc. In other words, we only do it when there's a *reason* to reset it.

I prefer to let adaptive strategy do it's thing, Ford has done some excellent work there, so let it do it's job.

Usually the symptoms of idle speed variation & smoothness clear up in most vehicles wihtin about 20 miles after clearing the ECU, a few take as long as 50 miles. I've never seen one whose idle was affected for hundreds of miles after clearing the ECU.

To answer your question, yes, when you have your custom programming done and you reinstall the Superchip, I would clear the ECU, just as I would clear it after removing the Superchip. However, that is not *required*, you can skip that and just realize that it's going to take longer for certain aspects of the new program to take real effect, that's all, so it's strictly up to you. We clear the ECU after every program change to effect that change as quickly as possible.

 

Hey All,

After adding an intake and exhaust system, should I need to reset the PCM, to get the full effect of the added parts?

Also, If resetting the PCM, with midgrade fuel, would the PCM relearn the octane curve, for the higher octane fuel?

Thanks in advance, R1968

 

Hi Ranchero1968,

Well, some people will do that right after installing those parts, and that does tend to speed the relearn a bit. However, that is not in any way *required*, and once you've had those parts on there for 500+ miles or so, there isn't going to be any difference in whether or not you cleared the ECU. This issue of clearing the ECU is most applicable when changing the program of the ECU, as it does make that happen quicker.

No, you cannot get your computer to reprogram itself for higher octane by clearing it and then running mid-grade. Anything more than 87 octane is a waste when running the factory program, as that is what the engine is tuned for. The only way to change that is to use something like the Superchip.

Clearing the ECU does not reprogram it, change it's program or change what octane the engine is tuned for; it simply forces the ECU to go back thru the relearn cycle & start the adaptive strategy adjustments from scratch.

Looks like a couple of very nice Fords you have there.

 

Mike,

Thanks, for the input. The questions actually came from a friend of mine. A debate, concerning possible learning capabiities of the ECU, running mid grade fuel.

Some areas during my travels, have 86 or 88 octane, not 87. I usually run 88 octane when this occurs, and have actually gotten 21 mpg @ 75 mph w/ cruise set. This has happened on several trips, while visiting my parents.
With that mileage gain, I was questioning the capabilities of the ECU to possibly learn or adjust enough to run 88/89 octane fuel.

I am still undecided, concerning my possible Superchip purchase.

Thanks once again, for the speedy input. Enjoy the weekend...
R1968

 

OK, understood.

To be technically correct, the later model FoMoCo's have an extremely limited ability to respond to higher octane. In the owner manuals, it usually says to not use anything other than 87 octane, which is correct for the factory program, as that is what it's actually tuned for. We have seen cases of check engine lights, *loss* of power and a drop in mpg from running higher octane on the factory program, and this is exactly why Ford warns to use only 87 octane. This happens because the higher you go in octane, the longer the A/F mix takes to ignite in the combustion chamber, and so the fuel curves have to be carefully calibrated for the octane level to be used. This will vary a bit from one vehicle to the next, and based on just how much octane you put in, usually a mid-grade is not enough to make those kinds of problems appear, that usually takes a full premium gas.

Now, in the newer vehicles, if you use higher octane for long enough, it is possible to see as much as about a 2% gain in power (max of about 5 hp in a 5.4), though not any real difference in mpg unless the energy content actually is higher in the higher octane fuel, and that certainly happens frequently.

So the bottom line is, you might pick up a couple of ponies using a bit more octane on the factory program, or you might make *less* power and see mpg drop from the fuel curves not being calibrated for the effective burn rate of the higher octane which causes no enough time for all the A/F mix to burn. There is that much variance in the response of these vehicles to higher octane on the factory program, so it's no wonder there is a lot of debate & confusion, even among "the experts."

 

Well, my SuperChip came Wednesday, and for my own curiosity, I filled up with my first tank of 92 on Monday so that by time I get to install the chip, I could time a few 0-60 times. This would eliminate fuel being a factor when comparing before\after chip install. (Chip ordered here at F150online from Performance Products on Sat., arrived brown truck express Wed. !!)

I have never used anything but 87 octane Amoco or Texaco gas. Well, after the second tank of 92, i can feel a slight difference in pep! I really did not expect this at all, cause the 5.4 is built to run on 87.

Could it be that I had a little ping all along and the ECM has been compensating by retarding the timing slightly?

Was going to install chip today, but it's raining.....maybe tomorrow. Hope mine isn't one of those that needs to be soldered!

 

Hi Rebel,

Yes, you could have had the knock sensor causing the ECU to retard some timing depending on the fuel quality, that is certainly possible. That generally happens with lower quality fuels, not with higher quality fuels, but you can get a surprise anytime. If you just happen to get a tank of fuel that isn't up to snuff, a higher octane and/or better quality fuel would allow the timing to return to normal and cause something like that.

 

Well, consistent with my usual luck, it appears that I have the ECM that needs to have a drop of solder. And on top of that, I also have the mounting bracket with the extended "lip" that had to be ground down to accomidate the chip. Imagine that.

 

Hi Rebel,

Well, try not to feel too bad, Murphy affects us all sooner or later, though I know saying that doesn't make it any more fun!

I don't know if you may have already contacted us, I don't know who you are due to the use of screen names here on F-150 Online, but if not, please let us know if you'd like our assistance with the jumper info, etc. We can always help you get up & running!