Q: Car misfires; crack in manifold

asked by on

My car is having multiple misfires. There is a crack in the manifold where the o2 sensor is.

Hello. A crack in the exhaust manifold near the O2 sensor can cause some poor sensor readings to the computer. The crack will allow fresh air to enter the exhaust, which causes the sensor to tell the computer that there is too much oxygen. This will send a message the computer to add more fuel, thus causing misfires. If the engine is running rough and misfiring without any actual misfire codes, then the crack may be the problem and the manifold will need to be replaced by a trained technician. A mechanic would typically scan the computer for any codes and see what the fuel trim readings are in order to be able to verify that the crack is the issue. If you do not have the tools to do this or don’t feel comfortable doing this type of repair, I would recommend the assistance of a certified mechanic that can replace any components causing problems in your vehicle.

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. Car misfires; crack in manifold

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: Q: Fan not working

The most common problem is the cooling fan switch located on the pipe that connects the upper radiator hose to the radiator in the engine compartment. Another issue is that there may not be sufficient coolant in the radiator. I...

Q: Fuel regulator replaced now showing p0172 and p0170 codes to replace fuel regulator

The codes P0171 and Po172 can be caused by other sensors like the MAP sensor, BARO sensor or ECT ACT sensors and each sensor will need to be checked to see if one is out of specifications.

Q: The car cranks a lot, turns off while idling, gas smell in the car

You need to have the fuel injection checked to see if the system has a fuel injection leak or a pressure regulator leaking. The fuel system, including the filter and pump lines, needs checking to see why you are smelling...

Related articles

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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...