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

 

James, I'm wondering if you remembered to disconnect the ecm from the dist. when you set the timing? Also knowing that the mini ram is a completely different intake than the tpi did you invest in a custom prom to help it run properly? I don't know for sure if you would actally need one, but I am sure that the intake will work better if you get one. TPS the company that makes the mini ram should be able to get a prom made specifically for you application. Also I have seen a bad MAF sensor cause some pretty strange drivability concerns. I think I might have a bad MAF on my 87 Formula. But I want to do some more test before I drop a buck and a half on one. Hope I offered some help.

 

i got all my code gone now , i relocated the MAF, because the miniram does not have a hole for it so i moved it to the intake, and the ecm timing pulg was, un plug setting the base timing and plug in after if was set. but it still backing threw the intake. at full thol. and no i did not get a custom prom.

 

James, what did you set you base timing at? Do you still have the stock cam and injectors? What is you fuel pressure set at? Have you tried bumping your timing up a few degrees and see what happens?

 

stock cam no it a comp cam .600 lift 245 dur. injectors are LT-1's and the fuel pressure is 45 psi all the time. i have played with the time i turn it up to 8 degrees and all the way down to -2 degrees and every where in the middle and it get worst form 0 to -2 degrees

 

James, I had the timing on my 383 with .560/219@.5 lift set at 6 btdc never had any problems, I raised it up the 15 just to see how it would run and it ran quite a bit better. I would try raising it up some until you hear some spark knock and then backing it back down and see how it runs.