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Smoke from exhaust when changing gears?

silviaz

By silviaz,
in General Automotive Discussion

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silviaz Experienced

silviaz

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Well my silvia has been running great on the road but have not been driving it at all almost while im sorting some stuff (so its been sitting for a week or so) and I was behind the car when i had someone else driving at and it seemed when the gear was changed that white / very light blue smoke was coming out the tail pipe? i know before i had smoke coming out of the engine because i didn't tighten the bolts on the exhaust manifold but that was fixed. Any other ideas what it might be? the iacv, pcv, air filter, fuel filter, throttle body, all that is either new or been cleaned but its not that. Timing chain was fixed so the car is in time. New oil was also added in.

Or maybe the car needs to be driven on a more daily basis? I also put new fuel in.

MoMnDadGTR Mentor

MoMnDadGTR

Posted
Posted

might be a long shot but I noticed when I had a boost/vacuum leak on my 93 gtr in ran very rich and this caused the car to smoke when I would shift without boosting the car hard. anytime I boosted it would run clean as fak. also if I let the car idle to long it would stumble. I addressed the leak(iacv and intake gaskets) and havent seen smoke since or had a stumble(plugs would fowl from sitting to long in a rich state until I gave it a good boost to clean it out. mine was faint white smoke but you could smell fuel not coolant or oil. I do get the odd smell of oil here an there but I think my -5s are on the way out lol....good luck mate

silviaz Experienced

silviaz

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On 3/18/2020 at 7:17 PM, MoMnDadGTR said:

might be a long shot but I noticed when I had a boost/vacuum leak on my 93 gtr in ran very rich and this caused the car to smoke when I would shift without boosting the car hard. anytime I boosted it would run clean as fak. also if I let the car idle to long it would stumble. I addressed the leak(iacv and intake gaskets) and havent seen smoke since or had a stumble(plugs would fowl from sitting to long in a rich state until I gave it a good boost to clean it out. mine was faint white smoke but you could smell fuel not coolant or oil. I do get the odd smell of oil here an there but I think my -5s are on the way out lol....good luck mate

thanks man but wouldnt i here if i had a vacumm leak? would this cause oil fouled spark plug to? car also has some fuel smell inside i tighted the exhaust manifold cause a while ago it smoked and it made alot of difference but then i could smell it again.,

 

MoMnDadGTR Mentor

MoMnDadGTR

Posted
Posted

ill try to keep this short. plugs could be black from fuel or oil. I would pop the oil cap off and take a sniff and see if it smells like fuel in your oil. this can be caused by fuel sneaking past rings when firing. I also over filled my oil real bad back in the day on a r32 gtr and this caused blow by and I had the black plugs with rich oil smell(also popped dipstick). im always optimistic and like to assume its not internal problems but sounds to me like your motor might be getting tired. once I dropped my oil when I over filled it and changed it to proper level my issue was completely gone and the fuel smell in oil was completely gone as well I think I caught it early enough before I did real bad damage. a motor that runs too rich all the time or to often will be very hard on the rings and can wash them out. I find even with my car I cant pussy foot it or it starts smoking a bit of white out exhaust and smells like fuel and my spark plugs start acting up. I get on it and it cleans up and goes like hell. ill keep in touch I think we can solve this. no you wont always hear a vac leak either. need to test system or spray brake cleaner around your motor when its running and listen for sputters. cheers

silviaz Experienced

silviaz

Posted
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On 3/22/2020 at 10:02 PM, MoMnDadGTR said:

ill try to keep this short. plugs could be black from fuel or oil. I would pop the oil cap off and take a sniff and see if it smells like fuel in your oil. this can be caused by fuel sneaking past rings when firing. I also over filled my oil real bad back in the day on a r32 gtr and this caused blow by and I had the black plugs with rich oil smell(also popped dipstick). im always optimistic and like to assume its not internal problems but sounds to me like your motor might be getting tired. once I dropped my oil when I over filled it and changed it to proper level my issue was completely gone and the fuel smell in oil was completely gone as well I think I caught it early enough before I did real bad damage. a motor that runs too rich all the time or to often will be very hard on the rings and can wash them out. I find even with my car I cant pussy foot it or it starts smoking a bit of white out exhaust and smells like fuel and my spark plugs start acting up. I get on it and it cleans up and goes like hell. ill keep in touch I think we can solve this. no you wont always hear a vac leak either. need to test system or spray brake cleaner around your motor when its running and listen for sputters. cheers

Hey man i noticed about 200km ago i changed my oil and its almost all gone! I went to pull up the dipsrick randomly to check and noticed the bottom part of the dipstick only had oil on it! now im worried that ive cause major internal damage. do you think this has to do with the valve guides?

silviaz Experienced

silviaz

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1 hour ago, GTSBoy said:

I refer you to post #2.

Do you think it could be the pcv valve? Reason i ask cause is i remember cleaning it out a while ago and there is a bit of rattle when you shake it but if you shake it in certain positions you cant hear any rattle.

 

silviaz Experienced

silviaz

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5 minutes ago, KiwiRS4T said:

Bite the bullet - do  a compression test.

I did so many times and latest is 130 across the board. But problem is there is oil on the pistons so that might be sealing it up. I had different readings each time but the car wasnt working then but now the latest is 130.

GTSBoy Grand Master

GTSBoy

Posted
Posted (edited)

Do a leakdown test, to see what the rings might be like. But keep in mind a few things. Compression rings are not oil control rings. Oil control rings are not compression rings. Leaking valves have nothing to do with leaking valve stem seals.

Edited by GTSBoy
MoMnDadGTR Mentor

MoMnDadGTR

Posted
Posted

could be a combination of a few different inperfections and weaknesses in the engine. I think its time for a motor rebuild m8 get her healthy again. at least that's what I would be doing at this stage. 

MoMnDadGTR Mentor

MoMnDadGTR

Posted
Posted (edited)

sorry for double post, but could try blocking pvc system and running a catch can setup to see whats going on, may be a waste of time tho...just to clarify are you running a sr20 or an rb in your car? I had a integra type r once with a b18c5 it burnt 1 litre of oil to 3 tank of fuel but would smoke like absolutely crazy from the exhaust blue. I feel like if your rings were shot it would smoke quite a bit more than just on shifts.  valve stem seals m8 or something weird internally maybe.....rebuild the engine and slap  a new turbo on it start fresh.

Edited by MoMnDadGTR

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