Q: My car starts to misfire really rough after running it for about 30-60 minutes, shutting it off then starting it up

asked by on

have gotten 8 codes. 1 says something about being lean on bank 1, other code says random misfire detected and 6 codes are each cylinder that have misfired. This only happens after running the car for a good length of time and shutting it off then starting it back up soon after
plugs are new, just changed oil, and timing belt has recently been replaced. My car has 170000 miles.
My car has an automatic transmission.

You have taken some great steps to try and resolve these issues. Looking to the spark system was a good choice. Plugs were a good start, but the distributor and wires may be causing the plugs to not receive the signal they need at the right time or voltage. You will want to check the spark at each plug, which can be done with a spark tester.

If this system is fine, you will want to look into the fuel pump and filter. Both of these can cause misfires if the fuel is not reaching the cylinders. Acuras built around this year have reported similar symptoms that have been cause by the primary O2 sensor failure. This would be the O2 sensor that is between the engine and the catalytic converter. Unfortunately, this is going to a process of elimination.

Was this answer helpful?
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. My car starts to misfire really rough after running it for about 30-60 minutes, shutting it off then starting it up

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: Stabilitrakservice light is in with traction control light

The stabilitrak and traction control systems may become inactive if the engine light is on. The code for a cylinder misfire on cylinder #7 may be due to the engine oil system containing sludge from improper oil change intervals. This...

Q: My car makes a loud humming like whoop sound when I accelerate past 50 MPH and gets louder the faster I coming from front end.

If the noise suddenly appears at 50 mph, then check the brake system as there could be an issue with the brake pads rubbing the rotors. If the noise starts off quiet and gets louder with speed, then check the...

Q: what does the clicking sound indicate when my car wont start

There are a variety of clicks you might hear when the car fails to start. Gentle clicks from under the dashboard mean the relays are activating, but the starter is not working. A strong tap from under the hood might...

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...
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...
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.