I have a V8 convertible and every time it starts up there is a puff of smoke out the back enough to be visible in the rear view mirror, it also seems to use oil, it went down to minimum after the service, topped up to full, and now back down to half full only about 2000 miles later, anyone else experience this?

 

First time I've heard this. It's definitely not normal.

 

Mine only lets out some water wapour right after startup (rather humid here now), and did not use any measurable oil before first service (one year, 10.000 km). Only done 1.000 km after the service, and oil level stays at the top mark - just as it did the first 10.000 km.

 

I've never seen mine smoke, but it did use nearly 2 quarts of oil in the first 4000 miles. Nothing since and I will hit 10k this week.

 

I would not say the oil use is all that excessive in comparison to my car, but it is a bit more than I am using. I add about a total of one quart every 5,000 miles. I check it monthly and usually it is down two or three hash marks which is about 1/4 of a quart. The car now has 13,000 miles.

Your puffs of smoke should be investigated. Usually a small puff of smoke means a valve seal or guide is letting oil into the cylinder. A small amount of oil gets burnt on start up resulting in a little smoke. This happens more with thinner oils, especially if the car is very hot when parked. It is not uncommon. In order to get it fixed under warranty I think you may have to prove very high oil use plus the puffs of smoke. I would try to get that data before pressing warranty issues. Again, the thin oils currently in use do contribute to higher oil use. This issue was recently documented by Consumer Reports as I recall.

A reading half way down the display means 1/2 a quart from full. You are using at least a quart every 4,000 miles. This assumes the dealer did not overfill it at the oil change. Reading at the full line could mean correctly filled, or overfilled by a quart or more.

My car doesn't give an overfill warning unless it is grossly (2+ quarts) too full; the low oil warning happens at about two quarts under filled, or a quart below the bottom line on the display. I posted a thread on this with pics of how much oil I had to extract to get the car to read exactly full after my first oil change.

Your oil consumption might be a quart per 4,000 miles, or two or three quarts in the same distance since you don't know how full it was filled at the service. I would not assume it wasn't overfilled.

One way to figure out the actual oil use you are experiencing would be to add oil carefully a little at a time until you reach the full line, then monitor and top it off, keeping track of mileage and the amount of oil added to keep bringing it back to full. If the car is already at the full line, I would extract a quart, check it, and if necessary carefully add oil until it just gets to the full line. Then monitor as above.

In my experience, even a quart every 1,500 miles will not be enough to get a manufacturer to admit the car needs repairs unless there are other symptoms of a problem. Your puff of smoke at startup might be enough, in combination with very high oil use, to get them to do something. If it wasn't so hard to pull the sparkplugs I would do that as well, on a cold engine after leaving it parked overnight. You might have one oily plug.

 

If by "down to half full" you mean roughly 4 quarts in 2,000 miles, then you definitely have reason to be concerned and enough that should get your dealer's attention. Do you see puffs any other time, like puling away from a traffic light? Is the smoke blue or white? Is the car still in break-in?

If your half full loss is only half way from max to add, then your loss probably isn't enough to get Jaguar interested, even if it's more than most of us are seeing.

I, too, see some white water vapor on start-up, but don't have any oil loss.

 

Thanks for the advice, to clarify, down to half full on the fill gauge not the engine half full, its definitely blue smoke and not water vapour it isn't like a smoke screen but its enough that when you look in the rearview mirror its a thin blue cloud there when you start up, guessing it could be worn valve seats. not terminal i guess but its not due a service until April so might get them to have a look before then. useful to know nobody else has this