OK so i just install a miniram on my 89 iroc. wasn't starting had no fuel pressure so i used some starting fluid to see if it would fire up and it back fired sending flames threw the MAF and blow up my intake. After that a fixed the fuel pressure crank it and fired up and ran. So i set the fuel pressure and the base timing. Got it to idle great and then rev it up fast and it back fire again and again so i checked the timing and fuel over and over still the same. Saw the check engine light came on so got a scanner and pulled codes, 23 MAT is too LOW, 33 MAF / MAP sensor too HIGH, 42 Electronic Spark Timing Moitor error. and that's where im at now. Never seen the codes before on my old set up. not sure what to check now the MAF look fine inside. not sure y it was back firing, it runs great just driving down the road but you get in to it and cuts out and back fires.

Ok reading some more on here and my 42 code was from the timing, the 23 code is for air temp?.. thinking to my self the miniram has to place for the MAF, so i guess that my 23. and my 33 is what ? when the engine back fired and torched my intake
and F my MAF.

thanks James

 

Look for a ground you didn't hook back up. It's possible these sensors all share the same one.