Skip the auto shop - Our mechanics make house calls

Q: Car will start but will not stay on

asked by on

I have a wrecked 96 4.6 auto Ford Mustang, I just put the motor in a 98 4.6 manual body the car will start but will not stay on. Mechanic took to dealership for programming, They said they could not due to wiring. What could be the problem? My mechanic is telling me that the 96 motor and 96 computer will not work in the 98 body and wants me to get a 98 computer. He is using the 98 key. At this point, I am confused.
My car has an automatic transmission.

Hi there;

I can understand your frustration, but to break it down simply; the electrical components (including wiring, relays and the ECU) on a 98 Mustang are not 100% compatible with the 96 engine system. When you swap motors, you need to ensure that the programming module is current to the vehicle year (not the motor). So, in this case, you need to have a 98 Mustang V8 4.6 liter ECU, and have it reprogrammed to link with your 96 motor. When automotive manufacturers started doing this in the early 90’s, it pretty much made swapping motors incredibly difficult for the hard working mechanic. However if you want the motor to work with that 98 Mustang, that’s the only way to make it work correctly.

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: Car window not rolling up

I’ll assume you have power windows. If the window is on track and does nothing when you hit the up button, it could be caused by several things. The switch, window motor, or wiring could be faulty and in need...

Q: hood latch locked before could. Lose hood and now hood is jammed and can't get it unjammed

Hi there: If the hood was having a problem closing and won't open now, it's typically an indicator that the hood latch itself is damaged or simply needs to be lubricated. The best way to have this issue repaired or...

Q: 1996 Jeep Grand Cherokee Limited Overheating

You need to check to make sure the cooling fan is coming on. If it is not then further diagnosis will need to be done by scanning the computer to see if fan control is turning on to see if...

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...
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...