I need help with my 1999 Acura CL 3.0.

So recently my car began driving rough (mainly at idle when the car is cold). The check engine light turned on at about the same time it began driving odd, at times the check engine light will flash or disappear, as if the problem is resolved. I had the car diagnosed and the codes P0301, P0302, P0303, P0304, P0305 and P0306 appear at different times or all together as multi-fires. The codes are never the same!

So far I've cleaned out the EGR ports, changed the spark plugs and spark plug cables and still the car fumbles at idle in the mornings and while its driving.

Any feedback would be helpful.

 

those codes are individual cylender misfires, and you got all 6 so ... the ignition system is a good start, mainly the coil, ignition module or distridutor, also (youd probably notice a gradual performance loss) has the timming belt ever been done? could be worn and jumped a cog.

just a couple dart throws but ....

 

Thanks, I'll take a look at the coil, ignition module, distributor and timing belt. I was also told that it could be a false connection in the ground cable which I plan to check as well.

Let see if any of these work, fingers crossed...

 

start with the easyest, most simple and work your way, good luck.

 

This happened to me not too long ago...

I have the 2.3, codes saying that all cylinders were misfiring. Not happy. Did a tune-up 20k miles before hand, didnt think it would be an issue.

So I inspected the spark plug wires, found out that one wire had a tear in the jacket that was arcing to the engine block, in turn causing the misfires. Replaced the relatively new wires... problem solved. Not sure if my experience helps at all since you already did a tune-up, but its better than nothing.

In your case, maybe double check the tune-up job and other ignition parts for arcing? Post what you find!