Compression testing and oil burning [Archive] - MX5 Miata Atlanta Owners Club

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drumbeater
12-19-2008, 07:56 AM
I got this 1995 Miata a couple of weeks ago. When you crank it, it burns oil and smoke badly for a few minutes, and then when it warms up it quits. I did a basic compression test while it was cold and got real low readings on 3 and 4. I tested it warm and got 180-190 on all cylinders, so I felt good about that. I have not tried a leak down on it yet.

I'm thinking bad valve seals or worn seats. If you look into the intake manifold it is covered with carbon, and the back of the throttle body flap had about a 1/8" thick layer of carbon.

How common is this on a 185,000 mile engine? I'm not going to pull the head and all that just yet. I'm doing the timing belt and water pump and calling it good and might just sell the car.
John

simontibbett
12-19-2008, 12:02 PM
Yeah sounds like seals or seats.

Mine almost has that mileage, smokes a little until warm. Just drive it till it blows, engines are cheap.

Doppelgänger
12-19-2008, 12:52 PM
To help with the seals, use Valvoline MaxLife for the next couple of oil changes, it will help. Also, give it an induction cleaning with Seafoam.

wildfire0310
12-19-2008, 01:01 PM
To help with the seals, use Valvoline MaxLife for the next couple of oil changes, it will help. Also, give it an induction cleaning with Seafoam.

I will agree with this. Mike remember me driving my car over to his place to figure what was wrong with my car. I was leaving a smoke screen at ever light I had to stop at. I used the maxlife for a few oil changes and cleared the problem. It is a great temp solution.

Doppelgänger
12-19-2008, 01:19 PM
Oh I remember the James Bond smoke screen :lol:

wildfire0310
12-19-2008, 01:30 PM
Oh I remember the James Bond smoke screen :lol:

Yea that felt so bad for the people off your exit cause I left such a huge cloud that people couldn't see through it :biggrin::biggrin::biggrin:

RotorNutFD3S
12-19-2008, 01:30 PM
Haha! Hopefully it wasn't the James Bond oil slick too.

wildfire0310
12-19-2008, 01:30 PM
Haha! Hopefully it wasn't the James Bond oil slick too.

lucky not... just nasty grey/black smoke.

That was saved for the white suby in the mountains from 4touge who's front got covered in oil blow by. :D

simontibbett
12-19-2008, 07:10 PM
My old ITC Civic smoked like a mosquito machine, in fact at an autocross the announcer said and here is the mosquito car LMFAO I laughed. I got black flagged at my first event at Road Atlanta is was so bad, so what do you do? Drain the oil, and run it basically dry! No smoke ;) (Honda D series can run with no oil, water, etc. Or water instead of oil)