Hemi won't start
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Hemi won't start
Last June my 5.7 Hemi with 290k miles died. I purchased a remanufactured engine and had it installed. It ran great but the red lightening bolt was flashing and the mechanic said it needed a new throttle body but it would be fine like it is. I drove it like that for 12k miles but suddenly it had a couple of episodes where it was very difficult to start and then finally wouldn't start at all. I purchased a new throttle body and replaced it, following the instructions on programming it. The throttle body light was still flashing but it started and ran fine for another 1000 miles.
I was driving it recently and while driving down the road the engine just shut off. As I coasted I put it in neutral and simply restarted it with no problem. This happened about 5 times until I reached my destination. About 6 hours later it started right up but about a mile into the trip it stalled for good.
Here are the codes that I got:
P0038 H02S Heater Control Circuit High Bank 1 Sensor 2
P0108 Manifold Absolute Pressure Sensor High Input
P0118 Engine Coolant Temperature Sensor 1 Circuit High
I've consulted the local experts and have followed their advice. First I replaced the PCM but that was no help, wouldn't start. I also changed the MAP Sensor, still no help. It won't start.
An interesting thing that I noticed: The plug going to the MAP sensor has 3 wires in it. They are for 5 volt positive, ground, and signal. I checked them with a multimeter with it disconnected from the MAP sensor and got these results...5 volts on the wire providing power, a good ground on the center one, and 5 volts on the signal wire. It would seem to me that I shouldn't get anything on the signal wire, that it should receive a certain amount of voltage between 0 and 5 volts to send back to the compouter. Am I right about this?
I'm at my wits end and don't know what to do next. Sorry for the long post, I wanted to provide as much information as I could. Anybody have any ideas?
I was driving it recently and while driving down the road the engine just shut off. As I coasted I put it in neutral and simply restarted it with no problem. This happened about 5 times until I reached my destination. About 6 hours later it started right up but about a mile into the trip it stalled for good.
Here are the codes that I got:
P0038 H02S Heater Control Circuit High Bank 1 Sensor 2
P0108 Manifold Absolute Pressure Sensor High Input
P0118 Engine Coolant Temperature Sensor 1 Circuit High
I've consulted the local experts and have followed their advice. First I replaced the PCM but that was no help, wouldn't start. I also changed the MAP Sensor, still no help. It won't start.
An interesting thing that I noticed: The plug going to the MAP sensor has 3 wires in it. They are for 5 volt positive, ground, and signal. I checked them with a multimeter with it disconnected from the MAP sensor and got these results...5 volts on the wire providing power, a good ground on the center one, and 5 volts on the signal wire. It would seem to me that I shouldn't get anything on the signal wire, that it should receive a certain amount of voltage between 0 and 5 volts to send back to the compouter. Am I right about this?
I'm at my wits end and don't know what to do next. Sorry for the long post, I wanted to provide as much information as I could. Anybody have any ideas?
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Registered User
Joined: Mar 2018
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If there's a short somewhere, it isn't apparent with a visual inspection. I guess I'll try to trace it some more today.
Thank you for the help.