96 maxima code 305
 

Here's a mystery. Brought my car in to a mechanic and they told me low compression in cylinder 5 (30 lbs). It had been hesitating at stoplights, but not when I would put it in park. Mechanic says new engine or new car. Not ready to give up. Called three different shops to do a second compression test as well as a wet test and leak down test. They have told me not to waste my $. Weird thing is that since I brought it to the first mechanic, check engine light has gone off and the car is running normally. I did get a 305 code with o2s, egr, cat, and es blinking on code reader. I'm considering dropping another engine if I can actually find a mechanic that will even LOOK at my Maxima. Advice? Answers? I'm thinking of just buying another 4th Gen.

I am amazed that you can't get a repair shop to do a compression check. That's how they earn their living. What are you telling them that makes them say no? Don't tell them you have been to another mechanic. Just tell them that the engine runs rough.

Is the 305 code from an OBD code reader or the CEL light blinking? One way means mis-fire on cylinder 5 and the other way means EGR temperature sensor. It sounds like the code is from an OBD reader, so you should tell us P0305, not 305. Without the P, it means the blinking CEL light method.

The check engine light will go off if the problem stops happening, but it will take a couple of days. If you have a mis-fire as code P0305 says, you will get other codes like O2 sensors and catalytic converter codes because you a pumping un-burned gas out the exhaust pipe.

Most common cause of a P030x code is a bad ignition coil. Sometime the coils get weak instead of totally dying and intermittently cause a code and then work for a while.

You can either find a mechanic to check the engine out or swap the coil on cylinder 5 with the coil on cylinder 1 or 3 and wait for the CEL to come on and see what code it is.