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Discussion Starter · #1 ·
Okay so this is an update from my last post About smoke coming from the exhaust whenever I start my car. Last week I took it to a mechanic shop that the dealer told me to go to I guess it’s his mechanic who works on all of the cars that they sell and the managers personal vehicles. The car was missing the PCV valve hose and they replaced it with a new one but there’s smoke still come in from the exhaust whenever I start the car up but it only happens when I start the car up it doesn’t happen when I accelerate but I can’t see if it is happening sometimes when I rev the engine it happens and water comes out which makes me think it’s just a lot of condensation in the exhaust system but I’m not totally sure I drove the car this weekend for about 200 miles and no overheating issues no milky oil and I don’t have a loss of coolant so I’m kind of in a fritz right now because it’s just irritating seeing the smoke come out my exhaust when I start the car can somebody help or give me a general idea what’s going on
 

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"...give me a general idea what’s going on "

My first impression, is that you're over thinking it. It's a twelve year old vehicle, and you're only just getting to know it. Ideally, there would be nothing at start up... but a few seconds of visible... in my book, that's not a problem... Keep an eye on your coolant, as you're doing. And watch the oil level. See how much oil is used per oil change... or per thousand miles (if it gets low prior to a change being needed).

Just for a reference, mine is an '05 w/165k. I'm a quart low at 8k mile oil change... so I start changing at 6k, and it's just a little low. It starts fine, idles & rides smooth, only a miner drip from a power steering hose (soon to be fixed), and coolant level is constant... It's fine, IMO.

I also don't look at my exhaust when it starts up ;) And if anyone questions you... then explain that the computer doesn't make the correct air/fuel mix till the O2 sensors get up to temp... and that takes a few minutes (gospel)
 

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I'm just seeing your post for the first time. If car is twelve years old it could be that the valve stem guide seals (located in the head) are cracked or hard and are letting oil seep past which is then burned in the combustion process. This usually happens after sitting for a few hours and on cold startups. This is not a serious problem unless you are losing a considerable amount of oil. Hope this helps.
 

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Discussion Starter · #4 ·
I'm just seeing your post for the first time. If car is twelve years old it could be that the valve stem guide seals (located in the head) are cracked or hard and are letting oil seep past which is then burned in the combustion process. This usually happens after sitting for a few hours and on cold startups. This is not a serious problem unless you are losing a considerable amount of oil. Hope this helps.
Okay, & yeah I’ve been monitoring my oil level and it’s been siting at the same spot, it’s not happening all the time. For instance today when I got off work it didn’t do it at all
 

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I concur with the above, ie valve guides/seals.

In the old days, the performance thing was hardened/sintered valve guides. AS they had different properties, they had slightly larger clearance. They would always "blow a puff of smoke" on start up, as when the car stopped, some oil would run down the valve stem, sit in the chamber. Start car = puff of smoke. It is slight, and not noticed when running, but accumulates when starting. Jaguars have oil seals on the inlets, not exhausts, so when I start my old Jag after sitting for a while = puff of smoke from oil running down exhaust stems. When running, that oil is blown out, when stopped, runs down. My Trident always has, always will (aftermarket hardened guides).

Stag did exact same when I tried a "new fancy oil" that didn't last long here; went away when I went back to normal oil.

It can happen when people use too low a grade of oil. For example, if 15W30 recommended, people get told "lower is better on cold startup" and go to a 5W something. Do that if temp range far lower, but I have seen people do it, smoke on startup/oil usage, go back to the recommended grade = fixed. If your car recommends two grades, try the one with the higher "low end" and see if it changes???? So if they say "can use 10w30 or 15w30" and you are using the 10, try the 15. Unlikely it would make THAT much difference, but worth a try.

It is annoying. But if ONLY on startup, then it would appear the fix would be heads off/guides checked/seals replaced (assuming they have seals, as said above, some didn't have them on exhaust, as inlet needs them (sucks oil in through guides); wheras ex blows out; but that is probably an "old car thing". So weigh up that work against the "annoyance."

Cheers;

:)
 
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