Q: Serpentine Belt broke How do i tell if its the Altenator

asked by on

Serpentine Belt broke, now car responds like the battery is dead. When i let the car sit over 8hrs i can start car but dies after like 5 mins. Should i replace both The Serpentine belt and Belt Tensioners. It shouldnt be the altenator in this instance right?

My car has 120000 miles.
My car has an automatic transmission.

A lot depends on *why *the serpentine belt broke. If the belt broke after 120,000 miles simply due to age, that’s fine, but if it broke because one of the rotating elements - the tensioner, pulleys, alternator pulley, and so forth - has a seized or rough bearing, unless you fix THAT issue, the new belt will break as well. So, before you install a new belt, all of the rotating elements with bearings have to at least be checked for roughness and noise, although once any pulley bearing get past a certain mileage, they will often just be replaced anyway because they most decidedly do not last forever (what happens is the grease inside these pulley bearings oxidizes and dries out due to the high heat from the engine). As far as the alternator, once you re-install a new belt, it is easy to test for correct electrical output and you definitely should do that. If your car is starting and running only briefly you might have an issue with your battery (the battery can be load tested to rule that in or out as an issue) or a more involved engine management issue involving the fuel, ignition, and/or air induction system. Your best bet is to just schedule a diagnostic of your starting issues, during which a certified YourMechanic technician can tell you exactly what needs to be done to get your car fully operational again, in addition to helping you with any belt replacements that need to be performed on your vehicle.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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
  1. Home
  2. Questions
  3. Serpentine Belt broke How do i tell if its the Altenator

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: Timing belt ripped and after weird loud sound

Good question. I don't think there was any damage done to your car. Belts break all the time, just put a new one on and it'll be fine. Your steering wheel became hard to turn because your power steering pump...

Q: Problem with acceleration

Hi. There are dozens of potential causes for your problem. It could be anything from a worn fuel pump to a clogged air filter. If the Check Engine Light is on, the first step is to retrieve the diagnostic trouble...

Q: Shaky suspension - 1995 Mercedes Benz E420

Given the amount of mileage on your car, this may suggest worn out shocks and struts. If you notice the car bouncing a bit more than normal or taking a few seconds longer to settle after going over a bump,...

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...