sr20 grey smoke only at idle

[c-los13]

ok before everybody starts saying "SEARCH DUDE!!!", i did..and alot...
its a s13 blacktop w basic mods. after doing a boost leak test on the motor i found out why my car (http://zilvia.net/f/#) wanst running as good.
the upper part of the intake manifold was cracked letting out a bunch of air. i got another one from a friend, i put it on....all good!
after driving for about 5 minuter i started to see a bunch of grey/white smoke coming outta the exhaust (http://zilvia.net/f/#) i reved it and it stopped.
ok so i check my spark plugs (theyre good), check hot
pipe for oil (http://zilvia.net/f/#) (nothing there), check oil to see if i had coolant nothing there either). SMOKE ITS ONLY AT IDLE AND WHEN THE CAR IS FULLY WARMED.
i took w the only mechanic i trust, and he said ITS GAS NOT GETTING BURNED RIGHT.
anybody?????:wtf:

[kojiki88]

Still running the stock T25? If so, when mine was on its last breaths it did exactly that. At idle I would see white/grayish smoke coming out the exhaust. If I revved it or started driving again it would go away. I'm not saying this is exactly your issue but it wouldn't hurt to look into it. Check to see if the turbo has excessive shaft play, maybe the seals have seen better days and that's whats causing the smoke.

[c-los13]

i checked the shaft play on the turbo inlet and there is no shaft play, i havent taken down the downpipe to see if the one on the back is bad though =(

[kojiki88]

Have you checked to see if any of the injectors are staying open and dumping excess fuel into the cylinders? Other then that I've ran out of Ideas of what it may be. Last resort it may be the Head gasket...

[c-los13]

how can i check the injectors?????
i replaced the upper intake manifold cuz it was cracked, i noticed the smoke after that, idk if it was there before......i took off the fuel rail and everything looked good so idk

[Vernal]

pop the rail off and with key in 2nd pos check for any fuel leakage

[c-los13]

ima check that right now

[c-los13]

no leakage on injectors
took off downpipe and i didnt see any oil
could it be the o2?
i had a friend that just ran without one and he said it ran fine besides the high idle
any more ideas?
btw oil still clean and so does coolant...
im next guess its the o2 sensor and fpr

[Banana_Cute]

your mechanic is right.

could be a bad map sensor, a bad fuel pressure regulator, a plugged up air filter or a bad injector.

[mewantkouki]

your mechanic is right.

could be a bad map sensor

This guy knows what he's talking about... :picardfp:

[c-los13]

i cleaned up the MAF, idk how to check the fpr, and my air filter is new
mewantkouki: be nice w guy man, at least hes replying =)

[c-los13]

tried to pull codes outta the ecu and realized my ecu doesnt have a screw! =/
its a j4 on an s13 blacktop

[Vernal]

fpr can be checked by seeing if theres any fuel in the vac line. are you getting bad mpg? fluctuating idle? any other symptoms?

[c-los13]

idle is perfect, no fuel on vac line, idk about the mpg..i guess its fine unless i dont floor it all the time. i bit better than my ka (no emissions).
ima throw this out there since it could part of the problem.....ive noticed that when i open the throttle in front the car sounds kinda weak =/ also i got hks ssq bov from a friend and compares to my friend's mine is kinda quiet too like if its not opening right...

[john891]

If it was fuel related the smoke would be black. It sounds like you have a blown turbo, Very common with the stock turbo.

[mewantkouki]

Valve stem seals.

[jesse_s13]

Isn't white smoke mean coolant?

[SlideOrDie831]

leaky injector would cause black smoke. looks to be your burning oil. just because it doesn't have any shaft play doesn't mean the oil seal is bad in your turbo. S13 SR are know to have bad blow by also. that could also be it. if they were your valve stem seals it wouldn't stop burning so, it's not that.

[john891]

Exactly. I have blown 3 t25s (on different motors) and they exhibited your exact symptoms.

[c-los13]

ok................................................ ...........
so a friend recommended to change the coolant temp sensor.......
i swapped it and just went for a test drive
SMOKE IS GONE!!!!!!!!
idk if ill come back tomorrow, but for now its gone.....ill keep yall updated

[c-los13]

Smoke is back
its gotta be gas
when i pulling into my house i gotta the car outta gear and i hear a "loud" on back of my exhaust, it even scared me!! And then my idle drop alot
hellppppppppppppppppppppppp this things is pissing me off

[Edwin562]

my old coupe threw grey smoke when turbo went bad... i noticed it but didnt pay attention to it, then found oil inside my intercooler piping.

[adam s]

Honestly 75% of the time grey/white smoke is a headgasket, IF it's a LOT, otherwise it's probably the turbo.

EDIT: I somehow missed "only at idle", in that case the headgasket diagnoses can be disregarded, I still think turbo though.

[c-los13]

Update:
It was the fuel pressure regulator
it was burning too much gas
it was NOT holding vacuum therefore making run super rich, even my oil smelled like fuel.
Now my question is........................can i use a frp from a ka??? They look the same
please answer this asap since i cant find a stock one and an aftermarket one is too expensive

[JDMRIDDAZ]

put an aftermarket one and dont cheap out on ur sr20

[c-los13]

i really dont cheap out on my motor
but the fuel ratio on both fpr is the same
has anyone done it? and succeded? an aftermarket is def an option but im still paying off loans i got for my motor swap so yeah..............
its 1:1

[warauto]

I have the same exact problem, I heard It was the valve stem seals. Now you are making me re-think my problem.

I ran thicker oil 15w50 and after a couple weeks....no more smoke at idle. Intermittent problems

[c-los13]

i put a nimo type a fpr and the problem still there
im leaning towards the turbo since the car is running like shit at all rpms
feels heavy
it goes into boost and evrything but it just doesnt feel right
ima check the compression tomorrow
im really dissapointed at this motor
should have gone w the ls1 when i had the chance =(

[copmagnet]

Too much fuel makes a dark grey/black smoke. Blown headgasket/water makes for a lighter white steam from the tailpipe. Oil burning makes a thicker bluish-greyish tinted white smoke with a distinct smell.

My T25 did exactly what you're describing when it went bad, I still have the turbo it still has no shaft play. But the new turbo doesn't smoke. Oil seals going bad won't necessarily cause shaft play from what I've seen.

[seeks14]

Turbo could be blow dude..
and for the RECORD running rich will cause a black smoke..
coolant will cause a white smoke..

[c-los13]

yeah its gotta be oil, it smells weird and it is a thicker greyish
it didnt think it was the turbo because there was no shaft play
thanks copmagnet, your reply was very helpful
btw what turbo did you go w????
id love to get an s15 t28 but it a bit too expensive

[c-los13]

my oil smelled like fuel thats why i thought it was fuel related
at least i got the fpr regulator outta the way

[c-los13]

the only reason why i thought it was fuel related its because my oil smelled like gasoline and my mpg was super bad, still is after i floor it i can see the needle goin down=(

[copmagnet]

yeah its gotta be oil, it smells weird and it is a thicker greyish
it didnt think it was the turbo because there was no shaft play
thanks copmagnet, your reply was very helpful
btw what turbo did you go w????
id love to get an s15 t28 but it a bit too expensive

I went with the GT2871R. Got a deal I couldn't pass up.

A t25 replacement is the quickest and easiest solution, or an S14/15 T28, but that would require a bit of fiddling with the hotpipe or a reclocking kit. I also had an issue with my fpr making the car run really rich, blew black clouds of smoke. FPR just couldn't handle the Walbro. Do you have a wideband on there to check your a/f ratio? Pretty handy thing to know. Especially on boosted cars. Good luck man.

Oh yeah, and just my suggestion, if you remove that turbo put some braided lines on it. Makes it a ton easier to reinstall, those hardlines SUCK. Stripping the oil feed in the block sucks more. Cracking the block when retapping the hole sucks even MORE lol.

[c-los13]

yeah ive taken off the turbo before when i first got the motor cuz the bolts were loose, yeah i think ima go w the isis one for now, kinda broke (like all 240 owner) lol, i really hope thats the problem