Check engine light?

Check engine light is normally nothing to worry about at all. If there were no noticeable issues with the vehicle (overheating, shifting poorly, missing etc.) Then it is most likely just an emissions issue (i.E. Faulty oxygen sensor). When it comes back on, take to local auto part store and ask them to scan your vehicle for trouble codes. They do it for free and the code(s) will pinpoint whatever the culprit may be.

BLINKING CHECK ENGINE LIGHT IS AN INDICATION OF A misfiring possible bad coil
driving for 45 min may damage the catalytic converter
and cause more problem
best to have it towed or checked close by for recommendation if you can drive it the distance you need to get to your mechanic

It means you should have the codes read, the computer(PCM) has stored trouble codes! Autozone will check them free, write them down and post them here for further help!

Standing by.

That's the cam sensor replace sensor

Need to know how to align it with the tool. And maybe a few tests to confirm? Here are some test:
CMP signal provides PCM information for fuel injector synchronization. The CMP signal originates
from Camshaft Position (CMP) sensor. Enter this system test only when instructed during QUICK
TEST. This test is only intended to diagnose the following:
? CMP, CMP/TSS GND, PWR GND, SIG RTN & VPWR Wiring Harness Circuits
? Faulty Camshaft Position (CMP) Sensor
? Faulty Powertrain Control Module (PCM)
1) KOER & Continuous Memory DTC P0340: Check If Engine Will Start

This DTC indicates PCM has detected a CMP sensor circuit fault. Possible causes for this fault
are:
? CMP Circuit Open Or Shorted To GND Or PWR
? CMP GND Circuit Open (Hall Effect Type CMP Sensor)
? SIG RTN Circuit Open (Variable Reluctance Type CMP Sensor)
? CMP Incorrectly Installed (Hall Effect Type CMP Sensor)
? Faulty CMP Sensor
? Faulty PCM
Attempt to start engine. If engine starts, go to next step. If engine does not start, P0340 is not
cause of no start, go to NO START/NORMAL CRANKTEST under SYMPTOMS in
TROUBLE SHOOTING - NO CODES - EEC-V - CNG & GASOLINE article.
2) Attempt To Re-Generate DTC P0340

Clear PCM memory. Start engine. Raise engine speed to 1500 RPM for 10 seconds. Return to
idle speed. Raise engine speed to 1500 RPM for 10 seconds again. Turn ignition switch to OFF
position. Perform QUICK TEST to retrieve Continuous Memory DTCs. If DTC P0340 is not
present, fault is unable to be duplicated at this time. Go to TEST Z, step 1). If DTC P0340 is
present, go to next step (for Econoline and Pickup 4.2L) or step 5) (for all others).
3) Check VPWR Voltage To CMP Sensor

Turn ignition switch to OFF position. Disconnect CMP sensor harness connector, located at
right front of engine. Turn ignition switch to ON position. Using a DVOM, measure voltage of
VPWR circuit between CMP sensor harness connector terminal and negative battery terminal.
See Fig. 49. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less,
repair open in VREF circuit.
4) Check PWR GND To CMP Sensor

Turn ignition switch to OFF position. Using a DVOM, measure resistance of PWR GND
circuit between CMP sensor harness connector terminal and negative battery terminal. See Fig.
49. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair
open in PWR GND circuit.
5) Check CMP Sensor CMP, CMP GND/SIG RTN Or PWR GND Circuit For Open

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Disconnect PCM connector(s). Inspect connector for loose, damaged or corroded terminals.
Disconnect CMP sensor connector. Using a DVOM, measure resistance of each CMP sensor
circuit between PCM harness connector terminal and CMP sensor harness connector terminal.
See Fig. 48, Fig. 50-Fig. 55. If all resistance measurements are less than 5 ohms, go to next
step. If any resistance measurement is 5 ohms or more, repair open in affected circuit.
6) Check CMP Circuit For Short To Power

Reconnect CMP sensor. Turn ignition switch to ON position. On Econoline and Pickup 4.2L,
measure voltage between PCM harness connector CMP and VPWR terminals. See Fig. 49. On
all other models, measure voltage between PCM harness connector CMP and CMP GND/SIG
RTN terminals. See Fig. 48, Fig. 50-Fig. 55. If voltage is less than one volt, go to next step. If
voltage is one volt or more, repair short to VPWR in CMP circuit.
7) Check CMP Circuit For Short To GND Or SIG RTN

Turn ignition switch to OFF position. Disconnect CMP sensor. On Econoline and Pickup 4.2L,
measure resistance between PCM harness connector CMP and PWR GND terminals. See Fig.
49. On all other models, measure resistance between PCM harness connector CMP and CMP
GND/SIG RTN terminals. See Fig. 48, Fig. 50-Fig. 55. If all resistance measurements are
more than 10 k/ohms, go to next step. If any resistance measurement is 10 k/ohms or less,
repair short to ground or CMP GND/SIG RTN in CMP circuit.
8) Check For Shorts In PCM

Reconnect PCM harness connector(s). On Econoline and Pickup 4.2L, measure resistance
between PCM harness connector CMP and VPWR terminals, and between CMP and PWR
GND terminals. See Fig. 49. On all other models, measure resistance between PCM harness
connector CMP and CMP GND/SIG RTN terminals. See Fig. 48, Fig. 50-Fig. 55. If all
resistance measurements are more than 500 ohms, go to step 10) (for Econoline and Pickup
4.2L) or next step (for all other models). If any resistance measurement is 500 ohms or less,
replace PCM.
9) Check CMP Sensor Output

Turn ignition switch to OFF position. Reconnect CMP sensor harness connector. Set DVOM
on AC scale to monitor less than 5 volts. Start engine. Using a DVOM, measure voltage
between PCM harness connector CMP and CMP GND/SIG terminals while varying engine
speed. If AC voltage varies more than.1 volt, replace PCM. If AC voltage does not vary more
than.1 volt, replace CMP sensor.
10) Check CMP Sensor Output During Cranking

Turn ignition switch to OFF position. Disconnect PCM connector(s). Ensure CMP sensor is
installed properly and reconnected. Connect DVOM between PCM harness connector CMP
and PWR GND terminals. Set DVOM on DC scale. Using starter, crank engine (DO NOT
allow engine to start) in short bursts for at least 10 engine revolutions.
If voltage does not switch from less than 2 volts to more than 8 volts, replace CMP sensor. If
voltage switches from less than 2 volts to more than 8 volts, ensure Hall Effect type CMP
sensor is installed correctly and synchronized. See CAMSHAFT POSITION (CMP) SENSOR
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under FUEL SYSTEMS (GASOLINE ENGINES) in REMOVAL, OVERHAUL &
INSTALLATION - TRUCKS - EXCEPT BI-FUEL article. If CMP sensor is installed correctly
and synchronized, replace PCM.
NOTE:
If engine has a miss and DTC P0340 is present, ignition,
alternator noise, Radio Frequency