I'm working on my nephews 2005 Dodge Neon SXT.

2005 Dodge Neon SXT.

It is missing on random cylinders. I changed the crankshaft sensor as that was the only code I was getting. Changed the sensor and then got a general code (300) and a missing code (304 I think but it is a code for missing).

Tested the battery with a cheap battery tester and it showed weak. The car doesnt have any issues turning over after sitting for a night or two.

Put it on my good tester and under load. Tests high in the green, 12 volts. Started it shows good, charging. Turn it off, let it sit. With the load test button it shows weak.

My load tester, testing the entire electrical system. So battery shows good. Charges good. Weak under load.

It is missing on random cylinders over 50 MPH.

I have looked around the web and seen this issue on multiple maintenance forums. The recommendation is almost always not to change the battery (Yet) because this issue could be a number of things. The problem being the generic 300 code not telling anything.

So should I go ahead and change the battery? If not what other issues might I look for?

Thanks

 

No answer but Ill add that I have changed the crankshaft sensor and put in a new battery. It is still missing on random cylinders. The codes are still 0300 and 0304 which tell me nothing since 0304 is still the crankshaft sensor. Any ideas?