I have a code 43 and code 33 in my 91 firebird with 350 speed density. I am looking for the diagnostic flow charts for the listed codes. Can anybody help??

 

43 is the knock sensor circuit, so check to make sure its plugged in. Have you been over there on the passenger side lately?

 

hey i have the same problem lol. its given me fits for two months now and still have not figured it out. I get about half throttle and i hear a rattling sound, then motor misses a few times and it goes away and runs fine. then the codes pop up. I dont do it till 2nd or 3rd gear to. 1st gear works great.

 

Yeah was there 1 month ago when I hooked it up when I installed the new engine and again last night . I am getting knock retard but no knock counts and I do hear what sounds like pinging at above 7% throttle. I pulled timing out via the prom but I still get code 43, so now I think I have false knock. The knock sensor is out of a 88 firebird formula 350 tpi, would that make a difference??? Everything I have read in the promboard states that I need to get the codes fixed before I can do any real hardcore prom tuning . So I really just need to know what are the steps to diagnose the codes if anybody can help

 

YES! It makes a difference. The 85-89 TPI uses one style knock sensor and the 90-92 uses a different style knock sensor. There's your problem right there.