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-   -   white smoke in exhaust (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/white-smoke-exhaust-851634/)

Houstonderk 07-13-09 11:21 PM

white smoke in exhaust
 
So I've been trying to narrow down smoke coming from my exhaust. It had a o-ring coolant problem and I did the o-ring trick with the iron weld stuff and it worked pretty well. No overheating and not losing coolant. My afm is kind of offset due to having a bigger turbo and the smoke smells more like fuel.

I have a gm IAT in my intake elbow from a previous haltech but now have the stock wiring and am trying to figure out if the sensor read the same? If so I could try to wire it to work with the stock plug for now, also would it actually cause that much fuel?

True2RX7 07-14-09 11:58 AM

Not that I'm 100%, or even a small bit sure, but My motor has been flooding on me pretty badly, and the smell of fuel very high. I finaly got it started yesterday (the only time...) and it was pouring white smoke out. It could be extra fuel getting in there.

Houstonderk 07-14-09 06:13 PM

I feel it is fuel. I forgot I have the walbro and have adjusted my reg down as much as possible but its around 60psi.

True2RX7 07-15-09 10:34 AM

I also keep having a problem with it constantly flooding, I do the trick to clean it out, but everytime I go to start it, it floods itself...

flamin-roids 07-15-09 05:40 PM

Typically white smoke means you're burning coolant. Blue means you're burning oil and black means you're running rich. If you had issues with the coolant seals before, I'm willing to bet you're burning coolant. And your car will run like ass if that is the case.

batmanfc 07-15-09 06:13 PM

Yea sounds like you are burning coolant to me and the flooding sounds like u are starting to lose compression. Usually when they constantly flood it mean you have low compression.

vato2000taco 07-15-09 07:33 PM

houstonderk 60 psi is very bad stock is like 37-40 ish ,to the other guy as mentioned earlier white is coolant if your turbo is water cooled it could have a blown seal my stocker blew out the seals and smoked white so i went bigger and waterless(oil cooled only) how bad is it smoking if its really bad like three dragsters doin a burnout its prolly coolant seals ooh yeah an ass load of oil being burned will be white also but im talking like quarts at a time

ITSWILL 07-15-09 07:53 PM

does the white smoke smell sweet? If so its coolant.

Houstonderk 07-15-09 10:03 PM

It just smells like fuel. Im not loosing coolant either which is why I was sure the fix was good. The reason why I feel its fuel is that this engine ran in another car with the stock pump for 3 days after the fix and was good. Swapped into mine and started smoking all the time and more at the startup. THe new car has the walbro and a 3'' straight exhaust with the apexi n1 catback and no cats as well.

vato2000taco 07-16-09 07:27 PM

only time i ever saw gas smoke white was when poured on hot coals cuz it didnt burn just evaporate kinda. ass loads of gas usually smokes black and if it were gas it would burn in the exhaust causing extreme temps in engine and cherry red exhaust that will catch ur grass on fire!!! we all know all to well about flames shooting out of exhaust so think for a second if raw fuel were in exhaust that means one rotor isnt firing properly or at all and when the other does fire shoots into exhaust and would burn any raw fuel . flooding on the other hand is black and fuel that is not completey burned and it still is black not white.
raw gas and acceleration will also cause scary loud backfires been there done that.

by the way u got all that work done and dont own a wideband yet?? thats the second thing i bought. first was an ecu !!

Houstonderk 07-17-09 11:15 PM

Here's a vid and it seems to look blue in it. Might be the angle though.
http://www.youtube.com/watch?v=yzkc4gRqJqk

blackrotary23 07-18-09 02:42 PM

yeah, it looks like it is pretty thick smoke. judging by the way it was bogging in the video, you probably have fuel problem. check the filter and definitely check to see if you have injectors leaking air into the rubber grommets that insert into the intake manifold and center iron. if that is not the prob, then replace your spark plugs.

jake1191 07-18-09 02:45 PM

Does the smoke dissipate after the car is warmed up? Another though is if the engine isnt completely broken in yet and the seals arent 100% seated could fuel be bypassing the seals? Just a thought....

*TOUCH* 07-18-09 03:15 PM

@ 60 psi fuel rail press, id have to say your running pretty rich....but then again, as others have stated, fuel burns black, coolant burns white.

Houstonderk 07-18-09 03:32 PM

I put my wideband in and adjusted the little turn screw until it was around 14 at idle and its starts up and idles better than before, but still smoke. The smoke stays there unless I hold the gas down as you can see when revving. Its not usually that bad as the video unless not warmed up. The adj reg won't let me go down on the pressure anymore so thats the lowest I can get it.

*TOUCH* 07-18-09 08:13 PM

what kind of regulator is it? also, do you run premix?

*TOUCH* 07-18-09 08:16 PM

also, i dont see how your getting 14 AFRs with 850 primaries @ 60psi haha. that sems a little high either way for a rotary, sure your wideband is calibrated? i get low-mid 12s with 800s @38psi haha

Houstonderk 07-18-09 08:27 PM

Its not the one in my sig. Its just a stock tii with the stock injectors. Mine blew so I had to swap one in and still have the fuel pump and a fuellab regulator.

vato2000taco 07-18-09 11:32 PM

ok from the video its blue smoke and not as bad as u explained that looks like oil seals in turbo is bad rebuild should be cheap if u diy just seals that is like less than a hundered dollars for turbo seals and bearings. Fuel would definately be black and wideband would not read below like 9 afr so u would be off the charts low if it were fuel
14.6 afr is perfect at idle but under boost u should be no higher than 12.5 and thats kinds high imo i run like 10.5 to 11.5 personally kinds rich is safer than lean any day even though they say lean is mean. too rich is bad too though.
Arroncake gained like 80 hp from leaning out his engine but he was still in the eleven afrs up from low tens i think

Houstonderk 07-20-09 09:07 PM

The only thing it does now besides small amounts of smoke is when starting after sitting for longer than 8 hours, seems that its missing or something till I rev it for about 8 sec then its normal. I'll try and get a vid of it starting after sitting.

RotaryEvolution 07-21-09 12:10 AM

if it sounds like it's running on one rotor and smoking at idle only when cold then the coolant seal trick is failing.

it's running on one rotor until the coolant is getting cleared out of the fouled chamber that is leaking water into it.

the video does look like oil but some coolants have tricked me before in particular lighting.

build pressure in the cooling system and crank the engine over without starting it(cut fuel and spark to the engine) and pull the plugs out, inspect them for water. water won't burn off the plugs with a lighter, fuel will.

60 PSI is way too high for idle fuel pressure, i set it to 40ish and verify it rises correctly then tune.

blackrotary23 07-21-09 03:09 PM

sounds like you have leaking injectors. take them out and have them rebuilt. then see if it runs any better. usually, injectors cost about 25-30$ each to rebuild them with new seals, o-rings, pintle caps, etc. if you are leaking coolant into one of the chambers, you can actually check the coolants color and that will tell you if you are. if it is a brown color, that means that you are leaking into the oil, not a good sign. if i were you, i would just rebuild the motor all together. at least this way you know that the engine is still in good condition and all seals are still intact and working.

vato2000taco 07-21-09 07:46 PM

you could just pressure test the cooling system if it wont hold 13 lbs of pressure then uh housten you have a problem!!

Houstonderk 07-22-09 12:10 AM

I might just drive it some more to check other stuff out. Here is one of startup and you can hear the hesitation during throttle then It clears after acouple of revs.
http://www.youtube.com/watch?v=ovKFxjskuXA

blackrotary23 07-22-09 05:32 PM

sounds like the car is choking on flem, lol. meaning that you have fluid leaking somewhere definitely. it almost sounds like it is flooding and then it clears up once the fuel pressure stabilizes. you probably have leaking primaries.


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