[HMG_E93]

I was due for an oil change so I finally got around to it this past Saturday. Followed the DIY by the book except I went with 7 qts of Royal Purple 5w-30. Almost immediately after I started the car the engine started shaking really bad. After about 15 secs of this the RPM blipped to about 1100 rpm and the shaking stopped. I reset the oil service counter and turned off the car. Started it again and the shaking came back and this time the CEL came on. I ran the codes and got P0300, P0301, P0304, P0305, P0306, and P00BC.

I tried swapping the plugs and coil on cylinder 1 with 2. It made no difference but it was getting late so I left it at that and would deal with it tomorrow. I cleared the CEL before I stopped. Next morning my brother needed to change his oil too and needed my car out of the garage. I went to drive it out and miraculously the shaking was gone. Restarted a few times but shaking never came back and no CEL.

Drove about 40 miles this morning with 50/50 highway/city and it drove just fine. Actually noticed 1-2 extra mpg and much cooler oil temp too. I'm just scratching my head wondering what the heck happened.

[gunnerxq]

Originally Posted by HMG_E93

I was due for an oil change so I finally got around to it this past Saturday. Followed the DIY by the book except I went with 7 qts of Royal Purple 5w-30. Almost immediately after I started the car the engine started shaking really bad. After about 15 secs of this the RPM blipped to about 1100 rpm and the shaking stopped. I reset the oil service counter and turned off the car. Started it again and the shaking came back and this time the CEL came on. I ran the codes and got P0300, P0301, P0304, P0305, P0306, and P00BC.

I tried swapping the plugs and coil on cylinder 1 with 2. It made no difference but it was getting late so I left it at that and would deal with it tomorrow. I cleared the CEL before I stopped. Next morning my brother needed to change his oil too and needed my car out of the garage. I went to drive it out and miraculously the shaking was gone. Restarted a few times but shaking never came back and no CEL.

Drove about 40 miles this morning with 50/50 highway/city and it drove just fine. Actually noticed 1-2 extra mpg and much cooler oil temp too. I'm just scratching my head wondering what the heck happened.

Ahh you forgot to drain the old oil when you put the new one in!