radman

I have a 89 suberban with tbi keep geting code 43[ esc] when check engine light is on is the spark retarded?? have replaced everything ...HELP

John86

the code is for a knock sensor. if it is bad it can retard ur timing. wat all have u replaced?

radman

I have replaced Knock senser, dist,egr,esc box,with scanner on we never get a knock indicated

MalibuMaxxSS

maybe replace the 89 suburban.........sorry I just dont beleive in dumping money in a no win situation.......

John86

u could have an ECM problem or a wiring problem.

radman

I have replaced ecm also, the short block has 40 k on it i just put vortec heads on it so i have 9.5-1 comp.and 4.88 gears and it is just a dog. I use this to hunt coyotes and plow snow. I know it is a heavy vec. butit has to go better. Ihave had this problem with esc ever since i got the truck.we never get a knock signal and block learn never gets below 140 , i have 15psi fuel preasure, is there any way to keep it from retarding spark??

My next step is ?? Probably go to carb and hei??