Hello,

Just noticed I have blue-ish colored smoke exiting out of my exhaust at wide open throttle sometimes.

The doesnt smoke on start up.

I do premix sometimes, about every 2-3 fill ups 8oz per full tank.

Stock OMP is hooked up

Is it normal for this smoke to be exiting the back of my exhaust?

My mods are
Power FC
DP, MP, Cat back
Non-sequential twins

 

car comp tested at 90 psi all rotors.

 

any thoughts??
bump

 

My best guess from years of reading the FD forums would be oil seals in your turbos going bad. Do you have oil in your intercooler plumbing?

 

your obviously burning oil from somewhere

even if you have good compression there is going to be some mixture of the oil in the combusion chamber due to the OMP but it shouldn't be noticeable.

i'd say check your turbos. i even have oil blow by in the intercooler piping but i don't have blue smoke. there should be a negligible amount

 

I just had the car modified from sequential to non sequential...

How long will the turbos hold up approximatly before they start to under boost..?

 

blue smoke = oil
white smoke = coolant

 

whether they are sequential or not will not determine their life expectancy

only how many miles and how much boost you are running on them will

 

Ok

i took the car out again today, and i just wanted to make some changes to my original post.

the smoke is gray smoke... most of the times it will shoot out of im doing hard pulls...

usually i see the smoke almost like it is igniting when i let off the gass after a hard pull. there will sometimes be a trail of greyish smoke.


Could my tail pipe possibly catching on fire?

im running 12 psi on the turbos, they are freshly ported, not new turbos but pretty decent condition

 

Check to see if your pcv valve isn't in backwards. I had this exact same problem due to it being in backwards!

 

Is it necessary to let the car sit at idle before you shut it off?

i used to do this when i first got my car

then i herd it was unecessary. so i stopped doing it.

I just drive off boost for the last 5 mins before i put away the car.


Letting the car idle and letting oil flow through the turbos and getting all of the oil out of the turbo is really necessary ?

Can someone explain what the exact purpose is when letting the car idle for the turbos?


If i just shut off my car and not let it idle long, and if oil is still inside my turbos or whatever, could this be sorta causing my light trail of smoke out the back of my exhaust once in a while ?

 

the whole point of letting the car idle before you shut it off is so the turbo housings or manifold doesnt crack due to sudden cooling

 

Do you have a PFC, and if so, who tuned it? If someone tuned it a little bit too rich under WOT that could explain grey smoke during WOT runs and during decelration after a hard run.

 

How long should I let my car idle after:

regular driving with a few boost runs...


and then when i am full out driving hard and boosting more often...


is it necessary to get turbo timer to avoid cracking of the turbo housing or manifold?

 

Read this: https://www.rx7club.com/showthread.p...ht=turbo+timer

 

Dumb question here
but i cant remember off the top of my head if the stock twins 93 are oil and coolant cooled or if its just one or the other..?

 

you sure it is grey? sounds exactly like secondary turbo seals are givin in...

 

We have (often troublesome) turbo coolant lines...

Dave

 

HAHA... Sorry.

I didn't realize you started that thread, also. So why did you ask the question again?

Dave