Skip the auto shop - Our mechanics make house calls

Q: Crank no spark after fixing seized engine due to bearing problem

asked by on

I need to know why I'm not getting spark.

My car has 155000 miles.
My car has an automatic transmission.

A: I'm assuming the engine was rebuilt, an...

I'm assuming the engine was rebuilt, and not replaced in this scenario. The first thing that came to mind was the crankshaft sensor. Did the new crankshaft come with a reluctor wheel? They usually need removed from the old crank to install on the new one. If you're not sure, remove the crank sensor and look into the hole. It is on the exhaust side of the engine block, closer to the transmission. Check to see if you have injector pulse if the reluctor wheel is present. You will need a noid light. If there is not a pulse, this would support a crank or cam sensor issue. Check for codes as well.

If you replaced the short block, or installed a used engine, and you are getting an injector pulse. Check for power with the key on at pin 3, white wire at the ignition coil connector. The power originates through the "main" relay and a 30 amp slow blow fuse labeled ECM. The ground pulse to the coils comes directly from the computer.

If you need help with this consider YourMechanic, as a certified technician can help you diagnose your starting issue and help you fix it accordingly.

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・Save up to 30%

Get a quote

What others are asking

Q: when the motor is cold it starts right up, when the motor has been running it won't start until the motor cools

Hi! Sometimes when electronic components are failing they can be affected by heat. They may work when cool but not when hot. The electronic control module on your Dodge that controls ignition spark is the suspected culprit here. I suggest...

Q: Dome light and trunk light not working all fuses are good

The lights are controlled by the body control module through the auto shutdown relay in the right instrument panel fuse box. Either the body control module is not activating the auto shutdown relay or the relay is bad and not...

Q: Where is the sunglasses holder in a 2012 Hyundai Elantra?

The sunglasses holder is a compartment for storing your sunglasses while you’re driving. This compartment is easy to access when you are in the car, as it is located on the ceiling, in between the front seats. To open the...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...