My wife drove through a good size puddle after a rain storm and now the car runs rough when I start it and there is a fuel smell. I can drive it but it continues to run rough. I havent tried to push it but I dont think the speed is limited (limp mode). The codes are p0301, p0158 and p0303. I have read through some of the posts but they all have a different combination of codes so im not sure if my issue is the same. I wanted to see what the possible solutions could be. Any feedback will be helpful.

 

Water may have found its way onto the cylinder numbers one and three coil units.

See the attached file showing the location of the cylinders for V6 engines. Bear in mind that with the X400, the engine is transverse, so Bank1 is next to the bulkhead when viewing the vehicle from the front.

If there is a misfire, neat petrol is going into the catalyst and can cause damage.

 

Thanks for the info, I have been reading more of the forum and I think you are right. My wife said she started to feel the problem almost immediately after driving through the puddle. I see others have posted steps and video on how to remove the intake manifold so I might give it a try. Does anyone have a recommendation on which replacement coil units to go with?

 

I took off the intake manifold today and cylinder 1 and 3 had water on the coils and plugs. Thermo told me to try to dry some of the water out with a paper towl and he was right. I was able to remove more water than expected before taking the plugs out. The plugs themselves had water on them also. For good measure I remove the coil for #5 and it was wet also. I ordered 3 replacement coils and will pick up new plugs as well. I will keep you posted. Thanks again for the feedback so far it appears to have pointed me in the right direction.

 

I replaced the 3 coils and put 6 new plugs in and the car is running better than before. I also found the vacuum hose that goes from the back of the intake manifold to the fuel rail was broken. i taped it back to together but I will be replacing that soon. i suspect this vacuum hose can give people trouble to find or see. it runs under the manifold a bit and it has a protective cover so if it cracks you wont easily see it. someone posted this issue before Intermittant miss-fire/hesitation.