My 99 RT with 162,000 just started throwing a "running too lean" code. Any thoughts? Could it be that the upstream O2 is on its way out but not gone enough to throw an O2 sensor code yet?

 

Good question, what sensors can throw a "running to lean" code? Maybe, knock sensors or 02 sensors?

 

it is either running to lean lol or else o2 sensor goin kaput

 

well i've had the AFX race ECU in for a while and I know that leans it out on the top end. but i've never had this problem before during daily driving or throwing the "too lean" code at all. any other thoughts?

 

check the fuel pressure, might be a clogged fuel filter or a bad fuel pump. The pressure should be 49 psi

 

havent had the chance to check the fuel pressure yet...but the CEL went off and now I have a new issue. Like I said the CEL is off. But every now and then while driving the car bucks and bogs down for about half a second and the CEL goes on for a second and then turns off again. The fuel pump is only about 5 years old, the crank and cam position sensors are only a year old, the fuel injectors are 2 years old, and i have a coil and wires with only a year or so on them. Could it be something as stupid as a bad ground wire? or is it still possible that it could be the fuel pressure?

 

a bad ground could cause it but,not certin on where to check . I doubt it would be fuel pressure cause it would not only do it for a few seconds it seems to me low fuel pressure would cause a constant problem

 

check this, there's some about cutting out due to bad ground;

http://www.techknowman.com/Dodge Neon/Dodge Neon.htm

 

are you talking about this part?

"Is your neon cutting out and just dying with no trouble code or check engine light?

Well in my case it was the PCM. The big multi-pin plug is soldered to the main circuit board. the main "Ground" points on the plug where it soldered to the circuit board had fatigued and broke loose. I also found 1 place near the back of the board. I dug out the potting goo and repaired the board.

This was effectively like doing brain Surgery on yourself with a steak knife and spoon. The Red circles are where I found bad solder connections

1. You must know how to solder well.
2. You can't be faint of heart to dig in to it. CAREFULLY! you screw up and
you buy a new PCM!"

 

its not dying at all....it is just bogging down for a split second and flashing the check engine once for about 2 seconds. then everything goes back to normal. It usually will only happen 3 or 4 times during most of a day of driving. its just annoying and very odd that the CEL would flash but not stay lit after the problem