996.2 Cloud of Smoke on Cold Start
04-02-2017, 10:08 PM
#16
Pro
Scored or ovaled bores could be a contributory factor, and in my opinion this is likely to be the next thing we all need to repair, (next gen IMSB problem if you like) with this Engine.
Mine has just been pulled apart due to developing a tick combined with a filter full of metal, prior to that, slight smoke on start up, nothing too bad, was fine otherwise, nothing noticeable most of the time.
Failure turned out to be thrust bearing that has let go, but during the tear down, we found all 6 bores to be oval and two are scored.
Hopefully yours is just over full/ Porsche AOS issues as Macster points out.
Nice to see another Green car BTW and good luck.
Mine has just been pulled apart due to developing a tick combined with a filter full of metal, prior to that, slight smoke on start up, nothing too bad, was fine otherwise, nothing noticeable most of the time.
Failure turned out to be thrust bearing that has let go, but during the tear down, we found all 6 bores to be oval and two are scored.
Hopefully yours is just over full/ Porsche AOS issues as Macster points out.
Nice to see another Green car BTW and good luck.
04-03-2017, 11:21 AM
#17
if I track my car or drive like a jack ***, it will smoke on the next day's cold start up. The OE AOS just isn't up to par to deal with really aggressive driving. I am saving up for the motorsports one as I do track the car 3 or 4 times a year. I only put 8L of oil in my car. That is about 2 or 3 bars down from the top. Anything more than that and she smokes very easily on cold start up after some aggressive driving/turning
04-03-2017, 12:19 PM
#18
Mine will smoke occasionally after sitting, however, I read that letting it idle for a minute or two after driving spirited or not will cut down on that issue. It seems to work for me.
AWD: Not to hi-jack this thread, but you still have your toy and am enjoying it?
AWD: Not to hi-jack this thread, but you still have your toy and am enjoying it?
04-03-2017, 12:55 PM
#19
Drifting
Very useful Macster and Ahsai. Imagine all the worry you have allayed The different dipstick markings is very interesting.Thanks.
https://rennlist.com/forums/996-foru...l#post11556505
https://rennlist.com/forums/996-foru...l#post11556505
04-03-2017, 01:02 PM
#20
and if you google "my porsche 911 smokes on cold start up" - you will get results of brand new 991's smoking on cold start up. Cars with less than 20k miles on them - smoke on start up.
04-02-2018, 09:12 AM
#21
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Hello all,
I have a 2001 996 C4 with 84000 miles that's my daily driver. Saturday changed the alternator (that has a story!) and MAF by indy shop- right after drove back for an hour got the light on, code was P0507 - Cleaned the TB, code. Sunday noticed white cloud of smoke on cold start and rough idle! same this morning but the engine didn't struggle! Milage has dropped from 23 to 17 !! Bad AOS?? Does it have to do anything with MAF that was changed?? Give it a time?? Thanks a bunch
I have a 2001 996 C4 with 84000 miles that's my daily driver. Saturday changed the alternator (that has a story!) and MAF by indy shop- right after drove back for an hour got the light on, code was P0507 - Cleaned the TB, code. Sunday noticed white cloud of smoke on cold start and rough idle! same this morning but the engine didn't struggle! Milage has dropped from 23 to 17 !! Bad AOS?? Does it have to do anything with MAF that was changed?? Give it a time?? Thanks a bunch
04-02-2018, 10:24 AM
#22
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Our cars are very picky about the MAF sensor. What brand/type of MAF sensor was put in? Why was it replaced in the first place? Unplug it and see if there is any difference in the way the engine runs. Since the alternator was replaced, did they break the oil filler tube? Inspect for any cracks. Make sure the oil filler cap is on tight. Check the air intake for leaks and all the clamps are tight. After checking all this, reset the DME by disconnecting the negative battery lead for a few minutes. That will put the DME at default base values. Then go for a drive so the DME can re-map based on the new MAF. Don't forget to plug the MAF back in.
Last edited by DBJoe996; 04-02-2018 at 10:42 AM.
04-02-2018, 11:20 AM
#23
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Thanks for the reply. Porsche MAF, after they changed alternator, they called me that engine check light is on
P1128 + P1130 ( never had that issue before). Could it be due to air leak that you said and not the MAF?? Checked/cleaned oil cap yesterday. I will check the rest tonight.
indy shop is a reputable with 30+ yrs and is in racing himself. Now I got smoke coming out on cold start!! GreaTT!!!
Taking it back to the shop.
not related to this post but during alternator ordeal temperature would go up to just after 0 on 180. I thought water pump is going bad (with squeaky noise), but shop checked everything and said cooling fan high speed is out. Changed the auxiliary fan but still temperature is same!
04-02-2018, 01:03 PM
#24
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All of your PCodes are pointing to a intake system leak or bad MAF. https://rennlist.com/forums/996-foru...e-opinion.html
Cooling fan high speed - they are talking about either the left side or right side radiator fan. Check the fan relays, after that it is usually the fan resistors if the fan runs at low speed. Run car and turn on AC. That will make the radiator fans come on at low speed. Check that there is air blowing out just ahead of each side front tire. When was the last time you cleaned your radiators?
Cooling fan high speed - they are talking about either the left side or right side radiator fan. Check the fan relays, after that it is usually the fan resistors if the fan runs at low speed. Run car and turn on AC. That will make the radiator fans come on at low speed. Check that there is air blowing out just ahead of each side front tire. When was the last time you cleaned your radiators?
04-02-2018, 01:11 PM
#25
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And also, it is very easy to leave a vacuum line disconnected when replacing the alternator, or screw up the routing.
https://rennlist.com/forums/996-foru...omponents.html
https://rennlist.com/forums/996-foru...omponents.html
04-02-2018, 06:18 PM
#28
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DBJoe996: Could this cloud of smoke be related to the recent change of alternator and MAF?? It started right after I pick up my car, did not have any issue before-
I checked the oil level and oil cap as suggested by other members.
I checked the oil level and oil cap as suggested by other members.
04-02-2018, 09:34 PM
#29
Seems unlikely, however a trip back to your mechanic would be a smart next step. Have them check the crankcase vacuum level. This will quickly determine if your aos has failed (which will cause white smoke on startup). Could be just a coincidence that this happened after your recent service.
Either way way your mechanic should be able to quickly diagnose the cause.
04-03-2018, 10:24 AM
#30
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This morning on cold start, more from passenger side , smells like 2 strokes motor bike ! Normal in 10 seconds- drove 30 miles, engine light came up, code:P1128 ! Taking it in tomorrow- 😤