So my 2000 Nissan altima is idling like shit, the engine is a KA24DE. The rpm’s bounce from 400rpm to 800 rpm, but it idles fine when fast idle is on or the air is on(because the idle is a little higher). I have replaced the 02 sensors, did a complete tune up, checked the egr, and checked for vacumn leaks. I get pissed and took it to a shop last week. They said cylinder #4 is not firing but it has spark, compression, and fuel. :nuts: They swapped injectors and swapped a distributer to try and resolve the issue, but it did not work. They also said the IAB is working as it should. The code it throws is a generic code for running lean, thanks Nissan, that really fucking helps.
if it runs fine other than at a low idle, it would make me think its not a fuel/spark issue and possibly an idle control issue. does this car have an IAC motor?
if its running lean, try putting an o2 spacer on the 1st o2 sensor. i used a spacer on mine to get rid of a cel, and it worked, but made my car run real rich, like my mpg dropped almost 3-4 mpg. i know its the best response, but it worked my nissan
If a cam was broken or valves were stuck closed there would not be compression.
Not to mension the noise and mechanical mess an engine running with a broken cam would make.
If they say cyl 4 is not firing do a simple test. Let it run and idle then pull the #4 plug wire. See if the idle changes at all. If cyl 4 is dead then the idle should have absolutely no change.
How do you know it’s getting fuel? But a screw driver to the injector and put the handle to your ear, you’ll hear a nice solid click if the injector is functioning properly. Compare it to the other 3 for rythm and frequency etc.
Is your coolant level good with all air bled? Don’t know about nissans but in a honda if you get an air bubble in your coolant it will make the intake idle valves do weird shit.
