Rough starting after replacing the spark plugs and coils

Just to be clear, the engine was running fine before you replaced the plugs and coil.

If that is the case, we need to make sure the coils are fully connected and not misfiring.

Here is a guide that will help with this:

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

However, if you have the old coils, I would suggest you swap them back on one at a time and see if any of them cause the issue to go away.

It is rare to have coil on plug coils all go bad at the same time so let's start with the reason on why you replaced all the coils and that may help with getting us on the same page.

Thanks

Okay. So, we need to find out if we have a misfire or a vacuum leak as both can cause rough idle.

If it is worse now, I would still go back through and change the coils back to see when it gets back to where you were as it is possible that you introduced another issue. So, it is best to get back to where you were.

Here is a guide that will help with you checking the vacuum leak:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Once we do this, we can figure out what is causing the rough idle as there are other things if this is truly a misfire. So let me know what you find, and we can go from there.

Thanks

Thank you so much for that video. Just to be clear you are talking about the little bit of a rattle or noise it makes when it fires starts?

If that is the case, did it not do this prior to replacing the coils?

That sounds like a rattle or tensioner issue that goes away once the engine has proper oil pressure.

Any time we have a noise that is only at first start up and then goes away within a second or two, it is normally related to oil pressure.

That does not sound like a misfire, nor would a misfire go away that quickly after start up.

Next, when you rev the engine can you hear this noise at all? Does it only do it on cold startups or can you shut the engine off and get it to do it over and over again?

There were issues with the hydraulic tensioners, but I think your engine was one year prior to them so that is most likely not it but this is what that sounds like.

That is strange because it doesn't sound like a misfire. However, if all we changed were plugs and coils, I would just take one of the old coils from cylinder 1 or 4 (one that wasn't misfiring) and swap it in one at a time for each coil that is on there now. Basically, put in for coil number one, if that doesn't change anything, move that coil to number 2 and replace the number 1 coil with the new coil that you just removed.

We need to limit the variables so I would stick with one coil that most likely did not have an issue.

Let me know if that doesn't make sense.