Skip the auto shop - Our mechanics make house calls

Q: Intermittent misfire that sets a random misfire code and three injector circuit failure codes.

asked by on

Intermittent misfire mostly when accelerating under load and hot. I have ran a couple bottles of Heet and and a couple bottles of Seafoam through the gas. I have cleaned the throttle body, IAT sensor, and IAC valve. I have replaced spark plugs, coil packs, throttle position sensor, camshaft position sensor, and crankshaft position sensor. And I have resistant tested the injectors (14.7 ohms each). However, it still misses intermittently.

My car has 109000 miles.
My car has an automatic transmission.

A: Intermittent and random misfires can be c...

Hello.

Intermittent and random misfires can be caused by many things. If all of those components check out, it may be possible that one of the fuel injectors is dirty or clogged, and is not delivering fuel properly. It may be possible that one of the injectors needs to be cleaned or replaced. Random misfires can also be caused by fuel pressure issues, vacuum leaks, or engine management system issues. A technician from YourMechanic can come to your home or office to diagnose your misfiring issue and replace the fuel injector if necessary.

Regards,

Eduardo YourMechanic

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: My car won't start after a break-in & attempted theft.

When someone breaks in the vehicle, the Immobilizer system shows that the doors were locked from the outside. When the doors are ajar from the outside when locked, the security would set so the vehicle could not be stolen. Look...

Q: #6 cylinder misfire. 1999 Ford Explorer

Hi there - unfortunately, pulling the plug on cylinder 6 is necessary for the next level of misfire diagnosis: is there actually spark at the plug while running? What is the compression on that cylinder (and any other - are...

Q: O2 sensors

Oxygen sensors don't work in that voltage range. Oxygen sensors range from .1 to .9 volts. When the vehicle is running normal the sensor ranges between .4 to .6 volts. The O2 voltage should change constantly going above and below...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
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...
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.