Skip the auto shop - Our mechanics make house calls

Q: Rough starts and engine dies at idle

asked by on

My van has had trouble starting. When it starts, there's a rough idle, and while that's happening, the van usually dies if you try to put it in gear. Once you're moving, the problems disappear. Our van has a little over 100,000 miles on it, and has been pretty reliable. This starting issue only happens once a month or less. When it decides to have problems, they go away after one round of rough starts. I was thinking it might be the outside temperature at first, but there's no pattern. Tried changing to different grades of gas, but that didn't work either. This all started before the 100,000 mile mark, though we did have the normal things done at that time - timing belt and spark plugs. We've also changed the battery and tried using fuel additive to clean out the engine. No change. The rough starts feel like when you're missing a cylinder. When it happens, I can gun the engine without any issues, but when it drops back to idle, it dies. The biggest challenge is keeping it running long enough to get it moving. Since it isn't happening while the engine is warm or cold, I'm not sure what what else to do. Do I need to change my spark plugs and fuel filters? Anything else I should look at?

A: If the idle air control valve or mass air s...

If the idle air control valve or mass air sensor is having problems. If the idle valve is sticking closed it can cause the engine to idle very low and rough, and will run fine if the throttle is held open.

The valve may come unstuck after the engine is ran for a minute. Try to have the throttle body and idle air valve cleaned out to see if the problem goes away. Also try and have the mass air sensor valve cleaned at the same time. This should fix the idle problem you are having. Otherwise a mechanic would need to verify the problem and if it only happens at first start and once a month then verifying the problem would be unlikely. Have the vehicle looked at by a qualified mechanic, who can diagnose your cars symptoms first hand and pinpoint what exactly is causing your car to die after startup.

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: Car continues to run after taking the key out of ignition

If the rest of the vehicle is staying powered up as well (radio, lights, etc.), then there may be a problem with the ignition switch. Otherwise, there may be a shorted circuit allowing the fuel pump and ignition system to...

Q: Electrical issues after attempted theft.

The only thing I could recommend on this vehicle would be to have a qualified mechanic check out the damages from the radio theft. The wiring may have been damaged and is shorting the system out intermittently. If all the...

Q: Truck overheats when temp outside is below freezing

If the engine is only overheating when temperature drops below freezing then the most likely cause is the coolant in the engine is freezing due to incorrect mixture with too much water. Have the coolant flushed out and replace with...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...