No start

KRYSTOFF_D

MEMBER
2007 DODGE MAGNUM
2.7L
6 CYL
2WD
AUTOMATIC
180,000 MILES

No codes in the the ECU.
New fuel pump, fuel pressure verified.
Battery new, tested and verified.
Ignition coils and plugs verified.
Starter, starter relays and all fuses checked and verified.

It was noticed that when the throttle body was disconnected and you attempt to start the car, the starter will engage and the engine will crank over but no start.
Plug the throttle body back in, no start no crank.
Manually push the butterfly on the TB open and closed and try to start the car it will crank but not start. Key off ignition and try again and no crank, no start.

I replaced the throttle body, same symptoms.
The new TB readout via a simple code scanner shows the TB at rest at 8.7%.

Again, no codes other then from connecting and disconnecting harness and sensors during the diagnosis procedure.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Just to confirm the issue, it only cranks if you unplug the throttle body? If everything is connected and you turn the key then the engine will not crank at all?

If this is the case, we need to check some voltages because at rest the throttle body should not be at that percent. It should be pretty much zero so let's check the voltages at the sensor on the throttle body.

Then we need to check the voltage leaving the PCM on the starter circuit. Clearly I suspect the PCM is stopping the start but normally throttle position doesn't factor in.

https://www.2carpros.com/articles/how-to-check-wiring

Let's start with this and go from there. Thanks

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