i have a 2003 S Type R with 73000 miles i noticed after car sits overnight or for a long period when i start up i get a puff of whit/bluish smoke from exhaust no codes or drivability car runs excellent, only when car sits for a long time i just threw in some injector cleaner is this a commen problem kinda embaressing when i start up in morning in front of Neighbors and car had 60k service done at dealer any thoughts

Mine does the same thing. Usually has to do with valve seals and oil leaking past them.

+1 on What Michael stated. Miine does the same thing and has for sometime.

I have 140K on the clock and have serviced regularly as well. Probably need to do a top end job on the motor as stated above to solve it. I can tell you that it hasnt caused any issued for me in the last 60K miles...

Oh and I have 72k miles on mine as well

You guys got me thinking!! My 2005 STR has 87K and at the most uses maybe a quart of oil every 5-6K miles but I can't see the tail pipes when I start it.

Do you get a blue cloud that floats back over the car?? Or just small puffs that can only be seen if you are standing at the back of the car?
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Mine does a cloud on startup and uses about a quart between oil changes

<----DITTO

Mine has a white cloud and uses a quart of oil between oil changes as well but that is 10K miles for me. I have always used Mobile 1 since new, but since hitting the 100K mark I now use the Mobile 1 High Mileage formula.

blue cloud that floats back over the car it seems i can start it get out of car and its still there lingering

If it's white smoke are you sure it's not just condensation in the pipes? This shows up more in colder weather.

Dave

With the way I beat on my 138k mile 03 STR, figured she's be the smoker. If it bothers you much or oil consumption is overly excessive, pull the intake and heads for a refit. S/C cars, rebuild/port the blower.

i know this is old, but from what i have seen most STR's blow smoke on startup. My mechanic said that its possible that somehow the car has oil squirters to help dry startup. He is no Jag Mechanic i told him he was crazy he said some Mercs have it.

smoke on start up , especially after sitting a while is almost always a valve stem seal issue or a valve guide issue.
Neither are critical repairs and dont affect driveability much if at all

There are some STR's that have oil squirters, so he wasn't so crazy after all.

I _think_ all STRs have them.

Would a thicker oil reduce the blue smoke on startup?

I wonder if the oil can contaminate and damage the O2 sensors and/or cats?

yes and yes id say . mine would puff a small blue tinge on start up when i got the car after a day or more parked , i done an oil change soon after , penrite 5/30 full synthetic and it made it worse , not such a small puff more of a ploom,
i have done two more oil changes since with penrite 10/40 with 250mls of morey's oil stabilizer no more smoke at all since , and quieter on start up also .
i really don't know if it was the morey's or the viscosity change or both though, ether way it wasn't a good look and I'm pleased it has stopped ,

I'd be surprised to learn that going from a 5W to a 10W oil made much difference. Possibly using a 'high mileage' type oil which has additives to soften seals might help.

The volume of oil lost with each blue cloud start up is actually quite small and shouldn't affect the sensors.