i have a buddy with a 1998 z28 with 5.3 heads #206, CC 273XFI, typhoon intake and 85mm TB, pacesetter midtubes. we been tuning it just fine then one day the B2 LTFT is bottomed out -100% so im like wow looked at o2 voltage and its still moving like normal and car runs like a turd, ive tried reseting the fuel trims via hp tuners and it wont even move a bit off -100. then i tried to do it while the cars not running/key on and still nothing.

any help would be awesome, im leaning towards ecm messed up....

 

Dead injector on bank 2?

 

I wish it was that easy done checked all injectors. I should still be able to reset trims and be zero once again but it don't. I checked for intake leaks around gaskets, TB, intake boot, maf, exhaust leaks and nothing found.

 

That's a PCM brain-fart value, LTFTs peg at +/-25% and
throw a too-rich or too-lean code if it's a real, sustained
mixture error.

 

You can't log many PIDs on the 98 computer as you can on the 99+ computers. Try logging less than 23 and see if you get a normal reading from it.

 

I did that and noticed I was at 25 PIDS and you was right I backed it down too 24 and now its logging just fine.

Thanks a million he was about to order a new ecu.

I have a 99 ws6 and it let's me log more just didn't realize that 98 were that much lower