Skip the auto shop - Our mechanics make house calls

Q: Brand new motor will not start

asked by on

My son bought a rebuilt motor from a company on the internet and he has never been able to get it started the only thing i can think of is that when he was putting things back together he had the battery hooked up and had every thing hooked up to the alternator and then dropped it and the sparks went crazy and after that he finished hooking every thing up and tried to start it for the first time and it would not start do you think he fried the computer the only code it comes up with is one that says something about the auto shutdown so I check the auto shutdown relay and fuse the they check out OK are the motors in jeep made different for different yrs I know that some 4.7 have either a 16 tooth or 32 tooth thing on the crankshaft and the motor has the right one on it is there something else that could be different here is the vin if it help 1J4GW48N44C102579 Thanks so much for your help and time

My car has 178000 miles.
My car has an automatic transmission.

A: Hi there. From the description you have pro...

Hi there. From the description you have provided, changing the vehicle engine, shorting the alternator and now a no start, is going to require proper diagnoses. The computer recognizing a fault in the auto shutdown relay circuit, is encouraging, the computer may be okay.

Shorting the alternator could have blown a main fusible link or fuse. The ASD relay may appear okay, circuit tests need to be performed to isolate the loss of electrical power. The crankshaft reluctor ring is the tooth thing, you have referenced.

Since there are so many possibilities. I recommend having your vehicle’s no start condition be diagnosed and repaired by a certified technician, such as one from YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Transmission shifts up and down randomly.

This may be a result of a faulty transmission control module. A faulty transmission control module may cause a delay in acceleration or erratic shifting of gears. The transmission control module has various sensors such as vehicle speed sensors, wheel...

Q: I have a 2011 Jeep Grand Cherokee with 277,000 miles (mostly highway). My hope is to get 2 more years (90,000 more miles) out of i

Considering the high mileage and the symptoms you are experiencing, it is very possible that you may need a new engine. Engine prices can vary greatly depending on where you live, which vehicle the engine is going into, the time...

Q: Car wont start and electronics acting up

As long as no water has gotten into the car, sight unseen I would suggest checking for loose connections. Positive and negative battery cables, not just at the battery. Check the other ends - where the positive cable connects to...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.