Anxious Mind And Rough Start Issues
They put in a quart of oil additive rather than oil, and a few rough starts plus a check engine light immediately followed. I've put toughly 22k on the vehicle since owning and have had zero issues, and just had the 3rd oil change. I have looked into the EGR threads and am debating if cleaning that entire system is a necessity.
Rough start included a sound as if oil level were low/valves clanking and then faded briefly. No audible indicators after first 10-15 seconds and no noticeable difference in power or fuel efficiency. Trying to think of all options here.
There was maybe 3 rough starts and 40 miles put on the vehicle between the time the additive was put in and getting it to the shop for a system flush and oil change. Code came back cylinder 1 misfire and technician suggested it was probably due to increase in oil viscosity that the motor isn't used to handling and a bit of friction occurring because of that.
Haven't had any issues out of the car and have had zero rough starts prior to this and am wondering if it may truly be as simple as the mistake and increase in oil viscosity, or (after reading a few threads) if I am looking at more significant damage. Also, there is a slight rattle in low idle as if a plate or pan may be loose? Haven't heard that prior, but is also new.
Have started the vehicle and driven 50-60 miles since oil change and there hasn't been a hard start, engine noise (clanking or etc.), or any other noticeable symptom since. Checked the coolant level and it seemed a bit low. Topped it off and will monitor, but haven’t had any noticeable issues prior to this moment
Any advice from anyone is much appreciated.
If its never been clean and you plan on keeping the car for a while, its a must. If you want to see how bad it is, just pull the EGR pipe, very easy to do, the visual should prompt you to do it.






