M[:@][:@][:@][:@][:@][:@][:@][:@][:@][:@][:@][:@][:@][:@]97 Camaro RS is misfiring any suggestions? So I had a SES on for about a month I knew it was my O2 sensor Bank 1 Sensor 1 was going bad or was already bad. Then out of now where my car starts rumbling and I was getting now power from the car. So I brought it to Auto Zone and I got the error code PO300 (random misfire) so I replaced the plugs and wires. Then was told could be the ignition module or maybe a few coil packs so I took them off and had them tested and it all came out good(ignition module took some time so they could heat it up). Heres my problem all the forums I see say things to do with the injectors or something fuel related but it seems to be running rich like its getting to much fuel. Is there anyway it could be getting to much fuel and not enough air? And if so what should I check to ensure all possible air issues are checked? If anyone has any idea please give me a hand this sux with no car!!![/align]

 

Anyone replying to this that can help please also send a post to jhazard112@hotmail.com.

 

How many miles? A clogged catalytic converter can cause misfires and lack of power. Clogged air filter could prevent enough air from getting in also. Bad O2 sensor can cause misfires and cause the car to run rich too.

 

i replaced the o2 sensor and if it was still bad wouldnt it show on a diagnostic test? i thought about the cat but from what i have read it would smell really bad and you would be able to tell almost immediately from the smell and the air filter is the next thing on my agenda.

 

it has 150000 miles on and it is not really back firing it did up until i replaced the o2 sensor after that it has since stopped back firing it is just misfiring now

 

Ok so I checked the air filter and while it was dirty it wasnt bad enough to cause any major damage even so i replaced it. Cleaned the points on the coil packs where they get the electric charge to and from. Tried it out still having problems. So now im wondering if maybe it could be something where the fuel is just dumping into the engine such as a fuel regulator or something along those lines. Any help I would really appreciate

 

does it hesitate when driving ? if you changed the plugs/wires, try to get a compression check, did you change the fuel filter ?

 

What makes you think it is running rich?
If the ignition stuff is good, random misfire is usually due to lean mixture, but a really rich mixture could also cause it.
Check the fuel pressure and pressure regulator using a fuel injection pressure gage. [*]Attachthe pressure gage to the fuel pressure service connection, located on the fuel rail.[*]Turn ON the ignition, do not start engine, repeat several times to get max pressure.[*]Gage shouldindicate 48-54 PSI (fuel pump test)[*]Start engine, at idle, thepressure should drop by 3 to 10 PSI (regulator test)[*]With engine idling, pull vacuum hose from pressure regulator, pressure should raise to 48-54 PSI.
[ol][/ol]

 

I have the same vehicle and it is exhibiting the same exact issues. I just bought the car so I am just starting to troubleshoot that. If you had any luck I would be interested in hearing about it.