Q: p0305 Misfire in Cylinder 5

asked by on January 08, 2018

I currently have an error code of P0305. I have already replaced the spark plugs and the one coil on cylinder 5, the misfire is still there. Many people have told that they can smell gas when the car is running. I replaced all in the intake gaskets in hope that there was some kind of leak. I have done a compression test and also have the freeze frame data and it will both be below.

Freeze Frame Fuel System 1 Status: Closed Loop Fuel System 2 Status: Closed Loop Calculated LOAD Value: 32.94% Engine Coolant Temp :174.20 F Short Term Fuel Trim - Bank 1: 14.84% Long Term Fuel Trim - Bank 1: 0.00% Short Term Fuel Trim - Bank 2: 3.13% Long Term Fuel Trim - Bank 2: 0.00% Engine RPM: 700.00 RPM Vehicle Speed Sensor: 0.00 MPH Absolute Throttle Position: 4.31%

Compression Test Piston 1: Dry 160 - Wet 170+ PSI Piston 2: Dry 153 - Wet 170+ PSI Piston 3: Dry 160 - Wet 170+ PSI Piston 4: Dry 155 - Wet 170+ PSI Piston 5: Dry 157 - Wet 170+ PSI Piston 6: Dry 155 - Wet 170+ PSI

My car has 100912 miles.
My car has an automatic transmission.

Engine is misfiring Inspection $94.99 - $114.99 Get a Quote

The fuel injector could be faulty and/or plugged and that would explain the high short term fuel trim on Bank 1 which contains cylinder No. 5. Another possibility is a vacuum leak around the intake to that one cylinder. If so, that can cause a random misfire. If the lobes on the camshaft are worn, that can cause a misfire and other inefficiencies as well. I would first check for a vacuum leak. If no leak, secondary firing patterns on the misfiring cylinder should be examined on an oscilloscope. The waveform will help narrow the potential causes to fuel versus ignition. Another possibility is the random misfire is due to intermittent faults in the injector and/or ignition components so although these components appear to be in spec during static testing, in fact they are not reliable and are later, in service, operating intermittently. Finally, the ignition and fuel driver circuits in the PCM for the misfiring cylinder could be faulty; that is the absolute last thing to test though unless you happen to have handy a known good PCM that you can substitute. If none of these possibilities pan out, you can request a misfiring diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Push rod keeps bending.
A common issue would be a sticking hydraulic lifter which can end up with enough of a gap between the top of the lifter and the push rod that the push rod can get sideways and end up bent. Another...
Problems going to reverse on a T 150
The first thing you'd want to think about is: does it do it in reverse and drive? If it only does it in reverse, you either got a problem with the transmission or your differential, the rear differential. One of...
What could be the causing loss of power while accelerating leading to engine stalling? 2011 Chevrolet Aveo
Hi there - based on the symptoms you describe, I suspect that either the throttle position sensor or the fuel pump (or fuel pump relay) (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-fuel-pump-relay) are failing. The result is either incorrect throttle position reported to the engine computer,...
There was too much oil put in my car it got drove about mile maybe before sucked back out it is smoking a lot how long will it con
The 2012 is sensitive about how much oil is in the engine. If it has been overfilled, you probably have oil in the exhaust system and the crankcase vent system. The first thing you need to do is make sure...
Faulty door locks
Hello, and thank you for writing in. Getting a second opinion is always a good idea. Your vehicle has the option to open just the driver's door, or to open all of the doors. Typically you click the key fob...
How do I fix my hydro-locked car?
An engine is a large air pump. It is best to remove the spark plugs (https://www.yourmechanic.com/services/spark-plugs-replacement) and crank the engine over with the ignition and fuel system disabled. This will blow out all of the water from the engine. This...
How do i unlock my 2001 nissan altima steering wheel
Hi there. You may want to have the mechanic read this article (https://www.yourmechanic.com/article/how-to-unlock-a-steering-wheel-by-spencer-clayton) on some possible ways to unlock the steering wheel. In most cases, the issue is caused by a malfunction within the ignition lock cylinder (where the key...
My key won't turn in my 2010 Volkswagen jetta
Hi there. This article might help you (https://www.yourmechanic.com/article/how-to-diagnose-an-ignition-key-that-won-t-turn) complete a few self-diagnosis checks you can complete to help your key become unlocked. I would suggest reading the article and completing each step before contacting a professional mechanic to complete a...
My transmission keeps slipping and the cars shuts off completely while I am driving I need help
This may be a result of a faulty transmission control module. A faulty transmission control module may cause a delay in acceleration or erratic shifting of gears. The transmission control module has various sensors such as vehicle speed sensors, wheel...

Related articles

A Buyer’s Guide to the 2012 Nissan Xterra
The The 2012 Nissan Xterra is designed for those who want a true sport utility that can still handle off-road driving with ease. Built on the same F-Alpha platform seen in the Titan and Frontier trucks, the Xterra also sports...
Top Five Selling Cars in Colorado in 2012
Colorado Colorado offers a varied climate depending on where drivers are located. Those in lower elevations see plenty of sunshine all year, while those in the mountain areas can see as much as 300 inches of snow. Due to this,...
Nissan Certified Pre-Owned (CPO) Car Program
If If you have been shopping for a used Nissan vehicle, you may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on...