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Hello, My name isXXXXX will try to help, are you sure that the engine is cranking enough and the speed sensor is picking it up, the sensor needs to see 50 rpm to start reading, you symptoms sorta sound like a slow cranking engine, If you have ET and lap top you can give it a external power source and watch the speed sensor with ET.. Just a thought..let me know.
Hello, thank you, XXXXX XXXXX do you have ET ( cats Electronic technition) on a lap top, you would have to give the data link external power so the lap top could stay on when reading the speed sensor.. lets go back a little though , you say you replaced fuel pressure valve.. was this the regulator valve in the filter base or the relief valve in the transfer pump.?/, also were are you testing the fuel pressure?and what is the cranking pressure?
Ok regulator filtered pressure tested and at 600 rpm should be 65-87 psi, this test port is on the r/s of the base, it sounds like you are almost there just the engine is spinning below 600
the unfiltered pressure is done at 2100 rpm at the top of the filter, and you should see 104-114 psi
what are your cranking RPMs? does the tach register?.. once you get it to start on either what ist the filtered pressure at 600?. If you have changed the regulator and spring, and the transfer pump all these pressures should be good..
if these are ok.. you have to plug it into CAT ET with the external power connector and monitor the speed sensors, to make sure they are getting a signal to fire the injectors..
here is the procedure..the other thing it will tell you is that the ECM is even on you did check the fuse to the ECM. it doesnt need the ECM to start on either..the ECM does need at least 11 volts and the engine to starter ground and starter to chassis ground on and clean connection.
Note: This may require Cat ET to be powered directly by the vehicle batteries or by a separate power source. If this is necessary, use the 167-9225 Harness (Service Tool Adapter). Connect the harnesses 70–pin connector to the ECM J1 connector. Connect the harnesses 9–pin connector to the adapter for the Cat ET service tool. Connect the red cable clamp to the +Battery terminal. Connect the clamp for the black cable to the −Battery terminal.
motor running at 600 rpm fuel pressure is 85 psi and at 2100 it is 106 psi the tach did work untill the motor was changed now it moves very little off the bottom also it is trying to fire when cranking.i have another c12 and check the fuel pressure with the ecm fuse out and at cranking it holds at 40 psi it might not be the fuel pressure it just seemed weard that they were not the same.