Q: Cranks but won't start.

asked by on

Cranks but won't start, especially in cool or damp weather. Just replaced the alternator, tensioner and belt and did not fix problem. Mechanic said MAF sensor was dirty, so he cleaned it and problem persists. Occasionally it will start right up, but usually only when weather is warm or vehicle has been used recently. A day or two of inactivity will almost guarantee that it won't start. My next thought was to replace the MAF sensor. What do you think, thanks for your time.

My car has 205000 miles.
My car has an automatic transmission.

This may be a sign of a dirty or failing mass air flow sensor. The mass air flow sensor is a unit in the intake system that monitors air intake as it is mixed with fuel prior to being injected into the motor. When this fails, this can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This may cause a hesitation, loss of power or jerking reaction when this sensor is malfunctioning. When this is not working properly, you may also notice a strong smell of fuel. Depending on the make and model of the vehicle and the type of ignition system it uses, this type of symptom can also occur when there is moisture inside the distributor cap causing a misfire as you try to accelerate. I would suggest having a professional from YourMechanic come to your home to diagnose your mass air flow sensor.

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. Cranks but won't start.

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: Van stalled, now cannot be started - 1991 Volkswagen Vanagon

Hey there. Your repairs seem to have focused on electrical (or lack of spark) issues. First, confirm that you now have a good spark at the spark plugs. If so, move on to the fuel system and check the fuel...

Q: What would cause my truck to rev up over 5000 rpm when I start it?

A faulty, or dirty MAF, is not the most likely cause of the RPM excursion. I would look for possibilities like a malfunctioning throttle plate or throttle body faults. A faulty or blown fuse in other electronically controlled systems can...

Q: Truck would not start this morning. 2011 Chevy Silverado. would not crank and service traction control came on. Help!

Hello, thank you for writing in. If the starter is not attempting to engage and turn over the engine, then you are likely not getting enough power to the starter due to a dead battery. You should try jump-starting the...

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 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...
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...