any idea's please

my 92 lumina z34 3.4 dohc wont start,the codes are as follows
#33-MAP sensor circuit high,and
#43 electronis spark control circuit
if you have not guessed it already.IM LOST.
so if you guys or gals could please give me the breakdown of what these mean.and some ideas of what to do. thanx in advance

some times it starts fine,and then an hour later it dont:confused:

new crank sensor,new spark plugs,new coil packs

Basics, do you have spark to the plugs, fuel pressure at the rail, will it start spraying carb cleaner into the intake?

yes,i understand that,ive got fuel pressure,i had spark,i dont know if i do now.
but i was just wonderinf you could tell me what those two codes mean and possible cure.
could the map sensor be dirty or fu##ed maybe?i have power to the injectors.
can it be cleaned?i
is it possible for a icm to work then not work then work again?
I DONT NO,
thanx guys

33- MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 6%.

This code most commonly indicates a vacuum leak. Your engine is known for intake gasket vacuum leaks, especially after the car warms up and all the different metals expand.

43- Knock sensor signal voltage was either above 4.8 volts or below 0.64 volts for 10 seconds.
The code for the EST circuit is 42, not 43.

This knock sensor code may indicate a bad knock sensor, a wiring problem to it, or that the engine has developed a knock or piston slap issue triggering the code.

If you actually have a code 42, EST circuit, that is one of the hardest codes to properly diagnose and correct, due to the fact that many different components can trip it (ECM, ICM, crank sensor, etc...)

33- MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 6%.

This code most commonly indicates a vacuum leak. Your engine is known for intake gasket vacuum leaks, especially after the car warms up and all the different metals expand.

43- Knock sensor signal voltage was either above 4.8 volts or below 0.64 volts for 10 seconds.
The code for the EST circuit is 42, not 43.

This knock sensor code may indicate a bad knock sensor, a wiring problem to it, or that the engine has developed a knock or piston slap issue triggering the code.

If you actually have a code 42, EST circuit, that is one of the hardest codes to properly diagnose and correct, due to the fact that many different components can trip it (ECM, ICM, crank sensor, etc...)
thankyou very much, i noticed a loose connection on this thing?on the right side of the block,i looked up all sensors on the net and found it to be the knock sensor.
so.... you just confirmed my guess.thank you very much
also do you think the code 33 would come on from turning the engine over and over to long? im gonna get my butt in gear and find out.
did i mention THANK YOU VERY MUCH:lol2: