I remember when I had the SSR, there was talk about if you used 87 octane fuel, the ECM would learn down and adjust the trim #'s accordingly, thus resulted in lower performance. And I know some members here use that fuel and that is fine if that is what you want to use.
Well I had forgotten what I did with the SSR and it was brought back to light after I read a similar post on the Camaro Forum. Seems like the factory was putting 87 octane fuel in the tank, hence when the owner took delivery, that is what they got or a combo of low and high octane fuel after the dealer fill. So they were saying how owners were pulling the ECM fuse to reset the computer, then the ECM would once again learn the trim #'s for high octane. That is when I remembered, that's exactly what I did with the SSR, and had great results.
So today, I pulled # 41 ECM and # 43 ECM Transmission and let them sit out for about a 1/2 hr. Reinstalled and checked all the other fuses, and everyone had to be seated properly, they all took a slight chick to seat, I was surprised as I thought I checked this over a year ago.....oh well
But let me tell you, the engine feels great, instant response, it also may be the cooler temps (68) but a nice difference. The reason I did it was not because I use 87, never have in this vehicle, but because sometimes I think I have had a bad load of gas at one time or another, so to me it was worth the time to reset the ECM fuse. It can't hurt, but only help.......

 

Fuel trim relates to rich and lean conditions, not octane. To reset the values unhook the battery for 30 minutes or so.

 

^^^^^^^thank you^^^^^^

 

if my clock lost the correct time then everthing is reset ???

 

I am under the impression that the type of fuel used will effect the fuel trim #'s. I may be totally off base in my explanation, but from what I understand, is that when you use low octane fuel, (87-89) the ECM will make adjustments for the type of fuel being used and adjust the ECM accordingly, therefore retarding the timing which would lead to a leaner condition in the engine, and cause the ECM to use the lower fuel trim #'s. Whereas if you use 93 octane just the opposite would occur and your timing would increase as per the ECM, therefore creating a more "rich" condition, and using the higher fuel trim #'s.
Yes you can unhook the battery, but you will have to redo all of your settings in the vehicle, our fuse box comes with its own fuse puller, so I think it's easier to just pull the fuse for 20 minutes or longer.

if that thank you is for me....then your welcome!!!

no, if you unhook the battery, you have to reset everything, pulling the fuse, you don't.....

 

Just to elaborate on theory of a bad load of gas that I may have gotten from time to time, is that there are times when coming out of 1st to 2nd gear @ WOT I hear heavy pinging for a second or two between the shifts and sometimes that also will happen during a passing situation using passing gear @ WOT. Now there are times when I do the forementioned and I don't hear any pinging at all. And I have found out that different brands of fuel act differently from each other, and sometimes you may be getting fuel from the bottom of fuel station tank and getting some moisture in your tank with your fill-up. And I also understand that our weather conditions affect how our engines will perform; heat, humidity, cold, temps, etc.
But I have also learned which fuel stations not to use anymore and which brands to stay away from, and especially if the tanker is in the station unloading, I come back the next day, that way I know I not getting fuel from the bottom of their tanks.........just some thoughts!!!!!
I just think it's a good idea to reset the ECM every 3 or 4 months to allow for any diffferences in the fuel quality you may be getting, a good time to remember is when you change your oil. As I stated above, it can't hurt, it only helps..........

 

Fuel Trim

The control module controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. The control module monitors the heated oxygen sensor (HO2S) signal voltage while in Closed Loop and regulates the fuel delivery by adjusting the pulse width of the injectors based on this signal. The ideal fuel trim values are around 0 percent for both short and long term fuel trim. A positive fuel trim value indicates the control module is adding fuel in order to compensate for a lean condition by increasing the pulse width. A negative fuel trim value indicates that the control module is reducing the amount of fuel in order to compensate for a rich condition by decreasing the pulse width. A change made to the fuel delivery changes the long and short term fuel trim values. The short term fuel trim values change rapidly in response to the HO2S signal voltage. These changes fine tune the engine fueling. The long term fuel trim makes coarse adjustments to fueling in order to re-center and restore control to short term fuel trim. A scan tool can be used to monitor the short and long term fuel trim values. The long term fuel trim diagnostic is based on an average of several of the long term speed load learn cells. The control module selects the cells based on the engine speed and engine load. If the control module detects an excessively lean or rich condition, the control module will set a fuel trim diagnostic trouble code (DTC).

 

thanks for a more detailed explanation, although I will have to read a few more times to have sink in the following link from one of the Camaro forums is what reminded me of the fuse pull on the SSR.
http://www.moderncamaro.com/forum/sh...ECM+fuse+reset
I know I don't fully understand how the system actually works, but I feel the fuse pull is still good to do......