Real quick did a 730 swap from a 165, and have just stared to really tune chip. Got the idle, and idle BLMs working well then started to drive and adjust VE tables. I got a formula off the thirdgen site, and everything was working great until...


Quick note I have my INT hard set at 128. So I can get my BLM's locked in close to 128 before letting the strim take over. So the first few chips my BLMs are in the 108 to 116 range. AFter a few chips I now have the blms ranging from 116 to 122. INT still locked at 128. Drove the car about 24 miles on the last chip with good performance, and no problems. I took it out today and now I get a CODE 45? CLeared code 45 and put the new chip I had done a few more changes to. Same chip just different VE table. Now my BLMS are at 116 for just about every RPM and KPA except idle. Using Datamaster I found the code 45 is set when the car hits 128 BLM and it then goes into open loop. Or is this the CODE 45 putting it in open loop, and the BLMS read 128 as they do when I first start it? Here is where is gets really wierd. While driving with the code 45, the BLMs dropped back to 116 and then it went back into closed loop. The code went away. From then on it stayed under 128 and I never got the code 45 again. That trip. Any ideas? Could my car be dropping out of closed loop for some reason, causeing the code? I did notice my O2 volts are very high they seem to stay in the .800+ range. Even when datamaster said I was running 124-126 BLM

 

It varies some, but in general when you set a code the ecm defaults to some preset settings. So the ecm doesn't stay in lean mode. So you will see 128 when not in learn mode.

As the O2's numbers begin to look ok, then the ecm again goes into learn mode.

You're initally so far off that the code 45 sets, then as the engine get warmer, it colds, then as the O2 starts to work again you go closed loop and the learn cycle gets things right enough to stay closed loop.

You need to find the rich spot that's the problem, and lean it down a little. Or if running a monster motor, set the timer for code 45 to a higher value.

 

MaskID $8D? I always thought that the INT had to move
X steps from 128 before the BLM would move.

RBob.

 

I figured it out. Stupid me had my BLM and INTs set to 128
started over with a fresh Aujp and all is good.

Thanks for the responce guys