Skip the auto shop - Our mechanics make house calls

Q: Engine turns off when driving, cannot restart

asked by on

After having both my catalytic converters replaced, I went to get the vehicle. A 1/2 mile later the car just shut off at 30mph. No warning lights, no sputtering. It's as if someone reached over and turned off the key. Attempting to restart it, the engine would begin to turn over for a fraction of second then stop. Almost like a battery was too low to crank. Shop inspected & Scanned codes:

P154500 - Throttle valve control system Malfunction P157900- Throttle valve control module, J338, Adaptation not initiated P10A700 - Adaptation regulating flap for intake air soiled

Replaced battery battery, Inspected throttle body, and it moves freely. Plugs and coil packs new. The car eventually just decided to start, but it would stall immediately every time right after startup. Adapted throttle body, and the car did start and run seemingly ok. Drove 15 miles, and died on freeway.

Scanned again: P154500, P10A400, P164D00 Cannot get it to turn over. Now mechanic says there are trans. codes

My car has 68000 miles.
My car has an automatic transmission.

Hello. It sounds like you have a voltage problem. It may be a bad connection at the battery or at one of the ground connections. Both will commonly occur. Any loss of voltage will cause some serious module communication issues. If the battery, alternator, and connections are fine then it may have a bad module. I have seen quite a few module issues on many Audi’s if the battery was not disconnected when the new converters are installed (because the welding can damage the circuit). A mobile mechanic may be best suited to address these issues. If you would like, a certified technician from YourMechanic can come to your home or office to inspect your electrical wiring, and make necessary repairs.

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!
  1. Home
  2. Questions
  3. Engine turns off when driving, cannot restart

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: it turns over but don't start

The engine needs three things to start. They are fuel, spark and compression. If you are missing any of these then the car will not start. You may have no fuel from a bad fuel pump, you may have no...

Q: My CV axle won't go in due to a metal piece in transmission.

Hi there. Check the CV shaft and see if the retainer clip is on the end of the splines. If the retainer clip is missing, then the clip fell off inside the transmission. Get a flashlight and a pair of...

Q: My car clicks once and won't start.

Prior to performing diagnostics be sure that you have a fully, 100% charged battery that passes a load test. Confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. If the immobilizer system...

Related articles

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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.