Misfire, codes p0302 and p0303

Hello thanks for using 2CarPros.

Checking actual values for misfire counter if its count at only at idle speed or at all conditions.then run our guide:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Thank you let us know the results.

Can I ask what the spark plugs looked like in each cylinder? White, grey, black?

Thanks for your reply. Plugs look good (we switched plugs to 1 and 4), misfires only at speed if you stay off the freeway no codes are set, customer was able to drive for two weeks with no codes until she went on the freeway. No discernible miss until around 2,000 under a load.

Yep, sounds like you may have a flat camshaft lobe. Lets remove the valve cover to inspect. here is a guide to show what I am talking about:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Please run down this guide and report back.

Thanks, I bet you are right. It never crossed my mind, never see that in newer cars (I'm 72 so to me any thing built after 1985 is newer to me). If we ever get it back I will let you know.

Please let us know what you find. We are interested to see what it is.