Codes, 12, 28, 43 on 92 LT1
Thread Starter
Race Director
Joined: Feb 2003
Posts: 11,672
Likes: 20
From: Lake Wylie SC
Codes, 12, 28, 43 on 92 LT1
Today was different. I went to join a buddy for lunch and found a flat tire, driver's rear. Okay, jack it up and there it was, a roofing nail right in the middle of the tread. My son had his plug kit at home and we plugged it. Now I hopped in the Vette to join my buddy and bingo, "service engine soon" light came on. It went out after a few minutes and the engine seemed okay for a quick run to lunch. When I got back home, I plugged in my code scanner and out popped a 12 (which is normal), 28 (which is the Quad-driver module), and 43 (which Helms says is the electronic spark control). I understand where the code 28 came from as I have a manual switch to ground the fans to "ON" signal. Now the 43 has me puzzeled. Several years ago, I installed Crane's roller rockers and they didn't set off the knock sensors so I figured it's okay. Why now? Maybe a loose rocker? Maybe a bad knock sensor? Would this make my Vette seem a little lazy? Before I get out the multimeter, anybody got some suggestions?
Thanks guys
Thanks guys
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
I have seen the spark retard set in the tune range around 10* in WOT (PE) and in some bins as high as 20* in closed loop. These numbers were max. and it would depend on the calculation of the ECM of how much it is actually taking off at specific rpm/load etc. You would need to scan /datalog to specifically know how much, and where retard is going on. I feel any retard becomes hindering to performance.
