[E__F]

Last week I changed my spark plugs in my 2019 g20 330i xdrive. 3 of the 4 came out fairly wet (image attached). I did some research and since I still have some CPO left I opted to take the car in to BMW. I brought the old plugs, test drove and spoke with the foreman. He said that a lot of these cars come in with oil on the threads and said that the PCV doesn't distribute everything evenly but that they looked fine for the millage (~40k miles).

After a fair amount of reading here on bimmerpost and elsewhere it doesnt sound like a good thing to have oil on the threads.

Is it normal for this much oil and carbon build up to be on the plugs for this engine?
What have any of you seen on yours/other's plugs?
Should i try a different dealer if this seems like something they are just overlooking?

Thanks y'all!

[dfc888]

I have a 2021 330i that spent its first 34k miles at BMW in South Carolina. Banks 1-3 with some rusty carbon. Bank 4 was a bit wet.

Have driven it 6k miles with no CEL or codes so far. Will probably monitor and check again in a bit. Haven't had a chance to bring it back to service to discuss yet.

[E__F]

Originally Posted by dfc888

I have a 2021 330i that spent its first 34k miles at BMW in South Carolina. Banks 1-3 with some rusty carbon. Bank 4 was a bit wet.

Have driven it 6k miles with no CEL or codes so far. Will probably monitor and check again in a bit. Haven't had a chance to bring it back to service to discuss yet.

No CEL or codes for me as well.

Car is back from the dealer. Notes from the forman on my invoice state that the oil on the threads is from "blow by" and that it is "normal operation".

Car still runs well since installing new plugs. Will probably take a look at cylinder 1 with a borescope after a couple tanks of gas.

[Jerolec]

Hi,

2019 330i built in germany here, spark plugs looked the same when got them out. No issue but still finding oil on the plugs a bit odd. Have you checked your new plugs recently? Have the since december 2023 and don't know if former owner was using cheap gas that could have affected the plugs. Also had a error code for the tank ventilation system. Have you ever had the same error? Trying to find a common issue.

[E__F]

Originally Posted by Jerolec

Hi,

2019 330i built in germany here, spark plugs looked the same when got them out. No issue but still finding oil on the plugs a bit odd. Have you checked your new plugs recently? Have the since december 2023 and don't know if former owner was using cheap gas that could have affected the plugs. Also had a error code for the tank ventilation system. Have you ever had the same error? Trying to find a common issue.

I have been meaning to check them but have been too busy. I was curious of what gas the previous owner of my car used too since it was a lease but idk if it could be related or not. I haven't gotten that error before.
Do you have a photo of your plugs? Did you end up swapping them out for a new set?