Hi All, I have a 1986 tpi in a 68 c10 it started running bad and stalling I changed the fuel pump, no good, found a ruptured fuel regulator diaphragm , replaced that and the injectors from SBFI stil, no good, it idles fine but hesitation when accelerated some times backfires through intake, Tps is at .54 replaced O2 sensor tried running it with the MAF disconnected it ran exactly the same just gave me a code that it was disconnected, it goes into closed loop no problem, seem the be throwing a lean condition code after it backfires, replace the complete ignition system except the pick-up coil don't think its ignition think its fuel, fuel pressure at the rail is 42 steady goes up to 50 when the vac line is removed from regulator any help would be helpful

 

Sounds like your down to a new maf or ecm.
You might need to datalog with tunerpro rt.
https://www.thirdgen.org/forums/tpi/...i-75-jeep.html

 

Have you checked your timing?, with the diagnostic connector disconnected? Should be 6 degrees BTDC.