Fueling & Injection - Injectors quit pulsing, need help on new startup




marksboy7
07-19-2012, 09:31 PM
Ok guys I need help getting my car started back for the first time with the new motor in it. I'll get one problem solved then run into another. I've got good fuel pressure, spark plugs are firing, checked all my sensors. We've come down to discovering that my injectors quit pulsing after it fires for about 5 sec. We thought that the theft deterrent system might be shutting it down. Anyone have an idea on what is happening here?


On a side note, I've got an interceptor scan gauge in the car and I can hold the throttle wide open, butterfly on the TB is all the way open, and my gauge tells me I only have 31% throttle. It's a new TPS sensor, even tried the old one, same thing on both of them. Tried doing a reset on it but I didn't know if that would help any with the motor not running.


tsquared38016
07-19-2012, 09:40 PM
I had a similar problem. It was either the cam or crank sensor. If the comp cannot tell the timing sequence it will not fire the injectors. You should be able to disconnect the sensor and try cranking. If it starts and runs then replace the sensor. If you have an AutoZone store they should be able to print you a diagnostic tree for the injectors not pulsing.


TT

marksboy7
07-20-2012, 12:25 PM
New crank and cam sensor still same thing. I have to cycle the ignition at least 3 times in between it firing up.


Old Geezer
07-21-2012, 06:22 AM
" We thought that the theft deterrent system might be shutting it down. Anyone have an idea on what is happening here?"

Have you had the VATS removed?

marksboy7
07-21-2012, 01:03 PM
I'm not sure. I sent the pcm to Frost for a tune to get it up and running but I don't know if the VATS was removed.