HELP with my new ws6 PLEASE!

[ws6susej]

Alright so i just bought a ws6 about 3 weeks ago. Has 112k original miles. The day after i bought the car the check engine light came on for p0420. I figured the lot that sold me the car cleared the code before selling me the car. So i called up the place and i was like wtf replace the cats they're no good. They finally agreed to fix the cats and right before i took the car to them i ran the codes again and now the p0430 code came up. They replaced both catalytic converters, got the car back with no CEL. Now im thinking the car is running good. Earlier today a BMW pulled up to me and we were doing a couple pulls. I had the a/c on because this texas heat aint no joke. It was just like 3 pulls nothing serious like i said i had the a/c on so it wasnt running 100%. On the last pull the check engine light came on and it started flashing, then went away. This was not the first time. It happened once before the first week i had the car, and it was also when i did a pull. Im thinking something is misfiring now, but i can not figure out what. The check engine light is still off. I still conneted the OBD scanner to make sure. And it said "no codes found". Wtf could it be? should i still drive the car? Like i said its happened twice. Both times it started blinking it went away after a couple of seconds. The first time the CEL was already on. The second time was after i replaced the cats and the CEL is off. Any help is appreciated, thank you.

[SMWS6TA]

Any stumbling or sputtering while you are WOT?



If the CATs were bad, possible the O2's need replaced as well.

[mrr23]

flashing usually indicates misfiring.

[Y2KArcticSS]

Check all of your plug/wire connections. At that mileage, you might even just replace them. It could be an overheating wire arc, or a bad coil. The bad part is the blinking light usually pops for a random/inconsistent misfire, leaving not much evidence as to which cylinder is the culprit. o2's might need replaced as mentioned above. I recommend RockAuto over parts stores for o2's if you can wait for shipping, they are half the price.

Depending on how long that car has been run with bad cats, it could have ruined a set of plugs even if they were new. If you're doing the work yourself, obviously start with the cheap/simple solutions and work your way up.

[ws6susej]

yeah i feel like the car was running kinda slugish on WOT. Today at the McDs drive thru i noticed it was stumbling and sputtering. I noticed because the car would idle normal then kinda sputter for half a second. It was doing it continuously. Seems like the car mainly only does this after its been ran a good 30 min.

[ws6susej]

Check all of your plug/wire connections. At that mileage, you might even just replace them. It could be an overheating wire arc, or a bad coil. The bad part is the blinking light usually pops for a random/inconsistent misfire, leaving not much evidence as to which cylinder is the culprit. o2's might need replaced as mentioned above. I recommend RockAuto over parts stores for o2's if you can wait for shipping, they are half the price.

Depending on how long that car has been run with bad cats, it could have ruined a set of plugs even if they were new. If you're doing the work yourself, obviously start with the cheap/simple solutions and work your way up.

yeah the mechanic at my job checked it out and hooked up the car to a live scanner. The car would act normal and then show misfires in different cylinders. Then show no misfires, then again show misfires in different cylinders, and so on. It goes and comes back continuously.

The mechanic said to try changing the spark plugs wires because he didnt think they were too good. The spark plugs were replaced by the car lot about a month ago. So im going to replace the wires and check the plugs while im at it to make sure they are still good. Hopefully this fixes the issue but im thinking its going to be the o2 sensors.

[ws6susej]

i bought new wires, the plugs are supposedly new.

The mechanic at my job hooked up the car to a live scanner and it showed multiple misfires in different cylinders, then go back to normal, then show misfires, then go back to normal. Im thinking its going to be the o2 sensors, which is probably why the CATs went out.

[SMWS6TA]

Is you swap plugs, go with NGK TR55or if you want a longer lasting plug NGK TR5 Iridium plugs. The TR55's are a better hotter spark plug but they're copper core so it's a 25k mile plug while the other one is 75k to 100k. Not as hot spark as copper but better than platinum


Wires MSD set for 5.3 trucks, same year as your car. The truck wires give you an extra 1-2".

[SMWS6TA]

Stick with Bosch O2's