keen 6 Report post Posted December 25, 2019 Can anyone give me a lead as to why my E90 2007 100000kms is smoking at idle. Not while running on the open road. All the check systems show OK. It's not using a lot of oil and it's not noisy. Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted December 25, 2019 hi Ken, which e90 is it? Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted December 25, 2019 Wouldn't be one of the 4 pot ones (316/318/320), would it? Quote Share this post Link to post Share on other sites
Gaz 1060 Report post Posted December 25, 2019 What colour is the smoke? Is it while the engine is hot or cold? Quote Share this post Link to post Share on other sites
keen 6 Report post Posted December 26, 2019 Hello. Yes it is a 4 cylinder. The smoke is blue. My informer says. It is when it's running cold or hot. The car is not down on power (noticeably) and it doesn't have that smell that comes from a worn out engine. Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted December 26, 2019 The n46 engine is notorious for valve stem seals failing. It happens to all of them as the valve stem seals were faulty from the factory, and at about where your current mileage is. Keep your fingers crossed that its the cvv. If it is the cvv, replace it and its associated hoses, and sell the car. Then buy a six cylinder or diesil powered e90. Quote Share this post Link to post Share on other sites
keen 6 Report post Posted December 27, 2019 Thank you for that advice. Can I assume that if I was to replace the faulty seals the new one's would be "not faulty"? I hear your advice. I kind of like this car, it is in good condition and all I need now. What is the "cvv" and what has happened to it? Quote Share this post Link to post Share on other sites
Gaz 1060 Report post Posted December 27, 2019 Probably unlikely to be the CCV (crankcase ventilator) if it's blowing smoke. Usually Doesn't blow smoke until the CCV is replaced as it is now working correctly Easy valve stem seals test is let the car idle for 5mins then rev it hard while stationary, if blows a heap of blue smoke then seals have failed. Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted December 27, 2019 If you replace the seals it will be fine as the new seals are good. Only problem is its a very expensive job. cvv is crankcase ventilation valve. These either fail or get blocked over time, as do its associated hoses. Do the test Gaz mentioned above to see where you stand Quote Share this post Link to post Share on other sites
keen 6 Report post Posted December 28, 2019 OK thank you will try this and see what happens. Can you give me an idea of valve stem seal replacement cost? Quote Share this post Link to post Share on other sites
Olaf 3317 Report post Posted December 29, 2019 thing about this engine is, you'll do the valve stem seals, and then you'll do the CCV stuff. and all will be well... for about five mins and you'll find oil leaks, and then the plastic timing guides will crack, the tensioner will go, the chain will jump a tooth... and it won't die as such, it'll just piss you off and not run quite right, until you relent and decide to get that fixed, and then you'll find the ++$$$ as it's valvetronic timing and all the gaskets have turned to hard plastic... and you'll wonder why you were so optimistic and should have bought the reliable safe-bet 6 cylinder equivalent when you had the chance. Sorry mate, these are epicly sh*t motors, pure and simple. Or you're blessed, and should buy lotto. 5 Quote Share this post Link to post Share on other sites
keen 6 Report post Posted December 29, 2019 Wow not a lot of positive there. Is the 6 cylinder faultless? Such a shame it's a very tidy car. What is the recommended model then. I just want something that will keep going for a while. I'm not hard on cars. I feel I know how to look after them. Quote Share this post Link to post Share on other sites
KwS 2425 Report post Posted December 29, 2019 The sixes arent "faultless", but the fours are utter dogs. Anything 323i or bigger will be a six. Obviously a 330i would be the best. 1 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted December 29, 2019 Valve stem seal replacement cost is in the thousands. Honestly the n46 was one of the worst engines bmw ever made, and you should sell the car before you get attached. Quote Share this post Link to post Share on other sites
Gaz 1060 Report post Posted December 29, 2019 Valve stem seals are about 2k with the head in place Quote Share this post Link to post Share on other sites
keen 6 Report post Posted January 2, 2020 I have tried the recommended test that Gaz advised and there was some oil smoke not a lot like big clouds of it. It was sort of more black smoke like unburned fuel. Is it a hard job to replace the CVV and its hoses? I will do this and sell it. 1 Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted January 3, 2020 Replacing the cvv and hoses is not too hard, just time consuming as the inlet manifold has to come off. Just take photos as you go and take your time. 1 Quote Share this post Link to post Share on other sites
SpS2000 0 Report post Posted July 1, 2021 imo if you did the valve stem seals you would do the chainkit at the same time. I get engines sent to me at home and do it for $1000 + parts Quote Share this post Link to post Share on other sites
