General reset ecu runs better?

[snakeyes711]

I only found maybe two threads after searching this , only one was from 2003, and none really had a concrete answer why after resetting my ECU my car seems to have more power. As in it pulls stronger. My fuel trims are hovering around Low 114%, mid 107%, high 104%. When I reset the ecu the low trim moves back to where it was first.... It just feels stronger, thats all I can really explain.

 

[Ceddy]

By resetting the ecu you reset the OctaneTrim.

Every time you get some Knock while driving, the OctaneTrim is reduced, and the ecu will advance timing less. The OctaneTrim is like a FuelTrim but for Knock, the more it is reduced the less timing Advance you will get.

The OctaneTrim was added as a safety feature in case you get a bad tank of gas.

 

[snakeyes711]

....Are you shitting me? It seems like its worse the more knock I get each time...

 

[Spoolin4Ever]

....Are you shitting me? It seems like its worse the more knock I get each time...

Exactly; it slows down the car (by: retards the timing) so you don't blow the POS to pieces . (BTW, it does not always slow it down in time, in which case you burn a valve like I did or a piston like some have).

I was one of the people that created a thread about this before.

 

[snakeyes711]

so, it doesn't ever go back up until I reset the ECU? that sucks because I run 93 with STP oct. boost....I feel like I been robbed!

 

[Ceddy]

so, it doesn't ever go back up until I reset the ECU? that sucks because I run 93 with STP oct. boost....I feel like I been robbed!

If there is no Knock for a period of time, OctaneTrim will increase and advance timing to its maximum.

 

[snakeyes711]

well, maybe I'll reset, and pull the boost back a bit so I don't really ever see knock. The max knock I really see is 7-8. It'll go up to 16-20 if I go near redline because I'm running out of injector, the IDC is like 94% but thats at 18 psi, and I don't really ever rev it past 5,500.

Is there a level of knock for it to do that? Or knock period? Besides 9 counts, before it pulls timing?

 

[jeffo]

The ECU will decrement the octane value if the knock is 3 or more. So, you need to see 1-2 knocksum at most to keep full timing.
Are you sure that your base timing is set to 5* BTDC, as checked with a timing light, as per the VFAQ? I find way too many guys running 7+ degrees of base advance.

 

[snakeyes711]

Yeah, I actually run at 4*. It feels better set at 4. So what happens at 3 or more, it just starts pulling 1* or it changes to a different map. Kind og like at 5 K ecu sets timing at say 20, if its adjusted octane value, whats it doing? Changing the whole map to lower tiing numbers?