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-   -   smoke screen... of death (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/smoke-screen-death-522417/)

speed_monkey 03-24-06 04:26 PM

smoke screen... of death
 
Before whenever I went over 3500 rpms or so ALOT of white smoke would come out of the exhaust, and gas mileage sucked bad when I took it up there. Now it wont even go past 3800 and smokes. Still terrible mileage. Here is a pic of what the smoke does to the exhaust...

http://photobucket.com/albums/a77/sp...t=100_0216.jpg

Could my ecu be messed up? I am getting the plug and play megasquirt ASAP but I would like a second opinion on what could cause this smoke.

Thanks

RotaryEvolution 03-24-06 04:40 PM

black smoke is excess fuel and would leave black sooty carbon in the tailpipe, i don't see any layers in yours so i am going to say more than likely the cloud is either oil burning off due to failed oil seals which are fouling the plugs or a coolant seal issue and the cloud is coolant burning which is more likely since there is condensation in the exhaust in that picture.

now keep in mind it could still be none of those cases i mentioned, during winter some mixtures when cold can just produce large amounts of normal condensation from your exhaust. water is a normal byproduct of combustion, if the cloud goes away after the engine is warm then you have a different problem. you could have many problems but warm the engine first and see if it still lacks power.

some things to note:

some thin white smoke on a cold engine is normal
thick white smoke on startup in the middle of a warm day is not normal - coolant in engine
any type of light blue hazey smoke is oil burning
black or grey smoke is fuel, indicating a severely rich condition and will leave black soot in the exhaust

classicauto 03-24-06 05:04 PM

notice any severe drop in your coolant level?

on cold start if you pull the cap off the overflow bottle, is coolant PISSING into it?

speed_monkey 03-24-06 09:20 PM

Nope, coolant hasnt gone down at all. There is a lack of power especially at higher rpms.
It has a pretty bad smell to it too. The oil does drop alittle faster than it should, but I have a leaky pan so I think that is the problem.

Im positive it is white, but Im not losing coolant. What gives? Tommorrow I will try to get a pic of the smoke pouring out while im driving.

InsomniacFC 03-24-06 10:17 PM

I had the same thing going on with my car. I fixed the timing and started using 20w50 and it all but went away. Just a thought.

WonkoTheSane 03-24-06 10:41 PM


Originally Posted by speed_monkey
What gives?

There are three fluids that have been listed as possibliites so far; Gas, Coolant and Oil. In your last post, you said that your oil level and coolant level are not dropping. This leaves one fluid , Gas. Your original post seems to imply that everything is fine until 3500-3800, then it all goes to hell. That, coincidentally, is the time that your secondary injectors are supposed to kick in. You may have a problem that your secondary injector(s) are messed up. I would think an easy way to check this would be to unplug your secondaries, then rev it up when you're in netural*. The car should fall flat on its face, but not have any white smoke.

*Note: I have never tried this test on a stock ECU, but I have run my car (megasquirted) without the secondary injectors hooked up accidently. I wouldn't try it under load (moving).

See what you come up with then?

LAN 03-24-06 11:35 PM


Originally Posted by WonkoTheSane
There are three fluids that have been listed as possibliites so far; Gas, Coolant and Oil.


I see only 2 fluids there :)

To my knowlege, it's what karack describes.
Pretty common knowledge.

13b4me 03-25-06 02:05 AM


Originally Posted by LAN

I see only 2 fluids there :)

To my knowlege, it's what karack describes.
Pretty common knowledge.

I believe he means liquid gasoline... Not "gas" as in a gaseous substance... :p:

WonkoTheSane 03-25-06 12:29 PM

^That's what I meant :) I was just saying that three things have been mentioned and the poster ruled out two...

RotaryEvolution 03-25-06 01:32 PM

i wouldn't consider them ruled out, though i doubt it is coolant, it takes a bit more coolant than it does oil to create plumes of smoke.

classicauto 03-25-06 01:49 PM

how many k's on this engine?

chiorx7 03-25-06 02:03 PM

time for a rebuilt


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