Well, I thought I had total control of the tune and was in open loop all of the time.

Not so.

I understand that BLM's and INT's are set to 128.

What else do I do to eliminate closed loop for now, while I get it tuned?

 

Set the closed loop enable temperature to the highest possible value and reset the ECM. The reset may or may not be required as some ECMs reset the BLMs to 128 at key on while others do not.

RBob.

 

Thanks!

So, is this the only step necessary, or is setting the BLM's and INT's at 128 also required?

Also, is setting the target idle higher a good idea? I mean, it could allow more vac at idle, especially with a rougher idling cam. Guess it would not be if it causes the TPS voltage to go above 1 volt.

What's hilarious is the factory tune had the WOT delay time at 30 seconds. Guess its because its a truck

 

Resetting the ECM will gaurentee that the BLMs are at 128 (do the battery cable dance or the ECM fuse dance).

Setting the desired idle RPM higher will not affect the TPS setting. Only the IAC counts will increase.

Common for the truck ECMs to have delay parameters for PE mode. Some will even decay out PE SA after a set amount of time.

RBob.

 

Jeezz... I saw the PE delay, but never really thought about it before. Mine is still set to 5 seconds. Thats not what I need for 1/8th mile blasts....

 

Hmmm. That name and local looks familiar. Do I know you

 

Yep. Its me.

Been lurking here for while now.

 

Quote:

What's hilarious is the factory tune had the WOT delay time at 30 seconds. Guess its because its a truck

The truck ecm's do incorporate a WOT delay but also use a second table for fast entry into WOT which has no delay. This table typically uses a higher TPS setting. There is also an "RPM to bypass WOT delay" constant.