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olliewagon
09-15-2012, 10:52 PM
does the crank senser control fuel injectors?

bigjim350
09-15-2012, 11:06 PM
Don't the crank sensor really controls anything, just sends a signal to the comp, which does control the injectors. What kinda problem you having?

Rattelsnake
09-16-2012, 10:23 AM
Not sure if it controls injectors, but when mine went out I got no spark.

4.3LXJ
09-16-2012, 10:41 AM
It does control the injectors by telling the ECM where top dead center is. It is like an injector timer. If the CPS is not functioning, then the ECM does not know when to fire the injectors.

olliewagon
09-16-2012, 02:22 PM
thanks . I thought that but not positive . Now one more question cam sensor controls spark in the same way corect ? I got spark but no fuel . pump is running and presure is good .

4.3LXJ
09-16-2012, 05:50 PM
Correct. Probably the infamous crank position sensor

Carves
09-16-2012, 06:17 PM
X 2 on crank sensor being the likely problem. They are both "hall effect" sensors and it seems to fail sooner than the cam sensor does ... since its mounted in a hotter, dirtier location ... and that type of sensor doesnt function well in those conditions.

Crank Sensor = Spark & Fuel, Cam Sensor = Fuel ...... if I read this the right way ...


CAMSHAFT POSITION SENSOR—PCM INPUT
A sync signal is provide by the camshaft position sensor located in the distributor (Fig. 3). The sync signal from this sensor works in conjunction with the crankshaft position sensor to provide the Powertrain Control Module (PCM) with inputs. This is done to establish and maintain correct injector firing order.

CRANKSHAFT POSITION SENSOR—PCM INPUT
This sensor is a hall effect device that detects notches in the flywheel (manual transmission) or flexplate (automatic transmission).
This sensor is used to indicate to the powertrain control module (PCM) that a spark and or fuel injection event is to be required.
The output from this sensor, in conjunction with the camshaft position sensor signal, is used to differentiate between fuel injection and spark events.

olliewagon
09-16-2012, 08:59 PM
Thanks again, I'll pick one up this week .