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Misfiring And White Smoke

S13 SecaBoy
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S13 SecaBoy Enthusiast

S13 SecaBoy

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hey guys...

i'm hoping someone on here might be able to help me...

i've done a search, but i cant find a thread with my problems...

its an RB20DET with fmic, 3" exhaust, fuel pump, t04e (brand new), splitfire coilpacks and irdium spark plugs... STANDARD ECU

basically, when i do a cold start it PISSES out white smoke (smells of fuel not oil) and it misfires on idle... but if you rev the car, the misfiring goes away but there is still craploads of white smoke coming out the exhaust...

but then as soon as you take it for a drive and the engine temp comes up to 'normal', all the smoke clears away (apart from a bit of black smoke cause its running excessively rich) and the misfiring stops on idle...

now.. i'm completely stumped as to why this would be happening... does anyone have any suggestions on what it could be?

i cant see it being a blown head gasket because a) the smoke clears up once the temp comes up to normal, b) the water in the radiator doesnt have a flim of oil on it and c) the oil isnt milky....

i believe i have two seperate problems... but they could be related, i dont know...

the first problem is that its running REALLY rich and i believe thats why the smoke smells of fuel and possibly why its misfiring because the spark plug is getting wet from too much fuel... sometimes it sounds like it running on 4cyl and other times it sounds like its running on 5cyl...

then the second problem is the white smoke which i have no clue on...

PLEASE HELP!!! i cant go on like this... :P

if you need to ask any clarification questions, then go ahead... ;)

thanks

ash

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Al Grand Master

Al

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Still can be a head gasket :P

You may have a minor crack that leaks into the bore, when cold, then as the engine heats up everything expands and seals up, till it gets cold again. If a gasket leaks water into a bore, the water will never mix with the oil, or vis-versa, and the water will then pass through the exhaust system.

All cars have white smoke in the mornings, but it really depends on how much you consider alot.

I am by no means stating that you have a blown head gasket, just advising that it is still a possibility and should not be ruled out because of the things you have listed.

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S13 SecaBoy Enthusiast

S13 SecaBoy

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There is a sensor for cold starts it might be stuffed

Have u ran the diagnotic on the ecu it might tell u what is wrong

good point, thats one thing we havent checked... didnt think it would cause all the smoke... :whistling:

Still can be a head gasket :yes:

You may have a minor crack that leaks into the bore, when cold, then as the engine heats up everything expands and seals up, till it gets cold again. If a gasket leaks water into a bore, the water will never mix with the oil, or vis-versa, and the water will then pass through the exhaust system.

All cars have white smoke in the mornings, but it really depends on how much you consider alot.

I am by no means stating that you have a blown head gasket, just advising that it is still a possibility and should not be ruled out because of the things you have listed.

i was told this by someone else today as well... i had never heard of this happening before... i didnt know the HG could have a 'minor crack'... i just thought that once they go, thats it, its gone!!

i call it "A LOT" when you sit in the car and you cant see behind you because of all the smoke...

Easy, White smoke on cold mornings here in brissy at the moment condensation, missfire due to running either colder plugs say 7's as they take a while to come to temp or the excessively always running rich fouling your plugs

Done :)

when i say "cold start", i dont mean just in the morning... it could be at 2pm in the afternoon... i just mean that it hasnt been started in quite a few hours so the engine is "cold"...

and its not condenstation in the exhaust system... my euro 'smokes' in the morning as well which is caused by condensation in the exhaust system... this is thick white smoke that bellows out of the exhaust pipe...

after all this, it was started today and driven back to my house from my mates workshop and there wasnt a puff of smoke at all and absolutely no mis-firing... so it seems like one day it will smoke and misfire, then the next day it will be fine, then the day after that it'll have problems again... :P

could a minor crack in the head gasket 'come and go' like that?

and would a minor crack in the head gasket cause it to misfire randomly at idle?

i'll start her up in the morning tomorrow and see if she smokes and misfires or not... :)

thanks for the suggestions guys... please keep them coming.. its greatly appreciated! :)

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S13 SecaBoy Enthusiast

S13 SecaBoy

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well, the smoke and misfiring is back today...

it kinda sounds like its choking on something on low revs, until you stab the throttle and bring the revs up then it clears up until the revs drop again... :?

any ideas from peoples??? :whistling:

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Green_s13 Proficient

Green_s13

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it sounds like you might have a leaky injector hence the running really rich, i cant say i have seen white smoke from fuel but it may be possible that the plugs are not burning it all and is getting onto your turbo and doing something odd with the seals, i had this problem with a silvia a few years ago.

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S13 SecaBoy Enthusiast

S13 SecaBoy

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no, still the standard injectors... i might have to test them out...

is there a way of testing them when they are still in the engine? or do i have to take them somewhere to get tested?

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Green_s13 Proficient

Green_s13

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easiest way is to remove spark plugs, unplug ignitor pack, then prime the fuel pump, if you can see fuel in any of the cylinders you have a leak. now it could be either the injector itself or is could be one of the o-ring's that seals then into the fuel rail.

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S13 SecaBoy Enthusiast

S13 SecaBoy

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green s13: okay... thanks mate.. i'll try that out... :P

anticeptik: can you explain that more? i dont quite understand what you're saying...

Edited by S13 SecaBoy
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Al Grand Master

Al

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Mate had the smae problem on a rb30et, he plumed his lines the wrong to the vents and was compressing the head or some shit
I know what you are talking about, but that does not apply to the RB20 or RB25, good idea though.
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S13 SecaBoy Enthusiast

S13 SecaBoy

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How about valve stem oil seals??

is there anyway of testing that without pulling the engine apart?

i havent had a chance to start the car since my last post... been too busy with work... :O

i'll update on saturday when i take it for a drive... :)

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S13 SecaBoy Enthusiast

S13 SecaBoy

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I actually started to think the same thing, but didn't come across this thread again till now.

okay...

any idea on how to check them?

or is it a job for the mechanics to pull the engine apart?

edit: just thinking about it again... would the valve stem oil seal cause BLUE smoke??

i dont have any blue smoke.. its only white... ;)

Edited by S13 SecaBoy
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Green_s13 Proficient

Green_s13

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vlave stem seals are usually blue smoke, but if the isn't being burnt properly you might get white smoke, but i would have thought that if it was that bad you would have the smoke all the time. i could be wrong

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S13 SecaBoy Enthusiast

S13 SecaBoy

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my issue is this...

IF it was using water, then straight away i'd point at the BHG... but its not using any water... :cheers:

IF the smoke was blue, then it'd point to an oil related issue... but the smoke is not blue and its not using any oil...

i'm gonna pull out the spark plugs and see if there is any fuel going into the cylinder with the car off...

firstly though, i'll check to see which cylinder is dropping out... that way i dont have to take ALLLL the spark plugs out... :D

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