Working With 3800sc s1 and have spark but fuel injectors are not pulsing. I have 50psi koeo. I also have fuel in the lines pump working. I have replaced the Cam sensor no luck. rpm needle bouces when cranking. Need help.
If the cam or crank sensor is not functional it will set a code and the injectors will not energize. Check for codes. With OBD 2 it's always a good idea to invest in a good diagnostic scan tool.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
So Its a 95 s1 so obd1.5 in the works of getting a scanner capable. And I have already changed the cam sensor. Wasn't sure if I should the crank sensor bc it has really good spark?
So Its a 95 s1 so obd1.5 in the works of getting a scanner capable. And I have already changed the cam sensor. Wasn't sure if I should the crank sensor bc it has really good spark?
OBD 1.5 makes a big difference. You can still read code but only a full featured scan tool like AutoXray, Actron, Bosch or Snap on will provide live data. We use an Actron III scanner here but all of the OBD 1/ODB1.5 stuff is now considered obsolete and hard to find used. As Joe has alluded to the VOM is your diagnostic test aid.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Been awhile since I did a series II OBD1 swap, get the wiring diagrams for your ECM and make sure you have all the necessary powers and grounds ran to it. Ran into a similar issue way back when SII swaps started becoming a thing, which is similar to your S1 swap.
[This message has been edited by jelly2m8 (edited 10-29-2025).]
It means using a volts/ohm meter to check for 12V power where it needs to be, ignition on and off.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
