Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/173061-misfiring-and-white-smoke/
Share on other sites

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.

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 :P

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! :)

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:

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.

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.

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... :)

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

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • AHHHH gotchaa, I'll do that once I am home again. I tried doing the harness with the multimeter but it seems the car needed a jump, there was no power when it was in the "ON" position. Not sure if I should use car battery jump starter or if its because the stuff that has been disconnect the car just does send power.
    • As far as I can tell I have everything properly set in the Haltech software for engine size, injector data, all sensors seem to be reporting proper numbers.  If I change any injector details it doesnt run right.    Changing the base map is having the biggest change in response, im not sure how people are saying it doesnt really matter.  I'm guessing under normal conditions the ECU is able to self adjust and keep everything smooth.   Right now my best performance is happening by lowering the base map just enough to where the ECU us doing short term cut of about 45% to reach the target Lambda of 14.7.  That way when I start putting load on it still has high enough fuel map to not be so lean.  After 2500 rpm I raised the base map to what would be really rich at no load, but still helps with the lean spots on load.  I figure I don't have much reason to be above 2500rpm with no load.  When watching other videos it seems their target is reached much faster than mine.  Mine takes forever to adjust and reach the target. My next few days will be spent making sure timing is good, it was running fine before doing the ECU and DBW swap, but want to verify.  I'll also probably swap in the new injectors I bought as well as a walbro 255 pump.  
    • It would be different if the sealant hadn't started to peel up with gaps in the glue about ~6cm and bigger in some areas. I would much prefer not having to do the work take them off the car . However, the filler the owner put in the roof rack mount cavities has shrunk and begun to crack on the rail delete panels. I cant trust that to hold off moisture ingress especially where I live. Not only that but I have faded paint on as well as on either side of these panels, so they would need to come off to give the roofline a proper respray. My goal is to get in there and put a healthy amount of epoxy instead of panel filler/bog and potentially skin with carbon fiber. I have 2 spare rolls from an old motorcycle fairing project from a few years back and I think it'd be a nice touch on a black stag.  I've seen some threads where people replace their roof rack delete with a welded in sheet metal part. But has anyone re-worked the roof rails themselves? It seems like there is a lot of volume there to add in some threads and maybe a keyway for a quick(er) release roof rack system. Not afraid to mill something out if I have to. It would be cool to have a cross bar only setup. That way I can keep the sleek roofline that would accept a couple bolts to gain back that extra utility  3D print some snazzy covers to hide the threaded section to be thorough and keep things covered when not using the rack. 
    • Probably not. A workshop grade scantool is my go to for proper Consult interrogation. Any workshop grade tool should do it. Just go to a workshop.
    • In my head it does make sense to be a fuel problem since that is what I touched when cleaning the system. When I was testing with the fuel pressure gauge, the pressure was constantly 2.5 bar with the FPR vacuum removed. When stalling, the pressure was going up to 3.0 bar (which is how it should be on ignition).
×
×
  • Create New...