2000 intake manifold

My mechanical experience is all based on a 5 hp Briggs and Stratton go
kart engine and a 1966 Chevy truck with a 328 (in 1994), so I'm a
little lost on a vehicle that include vaccum hoses and electronics.

(The local shop that has done all the work for the last 6 years just
went under, so I decided I'm going to start maintaining the Miata
myself.)

I have a 2000 Miata that I bought new. I've changed the oil every 5000
miles and drive about 360 highway miles a week. I currently have
95,000 miles. The only other maintainance is break pads and clutch
slave cylinder.

I took off the top of the intake manifold to fix the EGR warning. I am
very suprised at how grimy it is in there.

http://battjt.soliddesign.net/intakeManifold

Is this normal? Is all this crud just from crank case vapor? How much
does the crud lining the intake effect engine performance? I'm
surprised that these surfaces aren't smooth; is that what gets polished
in a "port and polish"?

I've read http://www.miata.net/garage/manifold/index.html and
http://www.miata.net/garage/egr.html .

Thanks for any input.

Joe

> wrote in message
ps.com...
> My mechanical experience is all based on a 5 hp Briggs and Stratton go
> kart engine and a 1966 Chevy truck with a 328 (in 1994), so I'm a
> little lost on a vehicle that include vaccum hoses and electronics.
>
> (The local shop that has done all the work for the last 6 years just
> went under, so I decided I'm going to start maintaining the Miata
> myself.)
>
> I have a 2000 Miata that I bought new. I've changed the oil every 5000
> miles and drive about 360 highway miles a week. I currently have
> 95,000 miles. The only other maintainance is break pads and clutch
> slave cylinder.
>
> I took off the top of the intake manifold to fix the EGR warning. I am
> very suprised at how grimy it is in there.
>
> http://battjt.soliddesign.net/intakeManifold
>
> Is this normal? Is all this crud just from crank case vapor? How much
> does the crud lining the intake effect engine performance? I'm
> surprised that these surfaces aren't smooth; is that what gets polished
> in a "port and polish"?
>
> I've read http://www.miata.net/garage/manifold/index.html and
> http://www.miata.net/garage/egr.html .
>
> Thanks for any input.
>
> Joe
Not unusual not to be smooth but looks very oily to me.

I cleaned the whole thing with STP throttle body cleaner, even spraying
some into the lower half of the intake manifold. It eventually started
and seems to run fine.

My local mechanic mentioned that there is always a lot of oil in the
intake, especially of Fords.

Joe

Joe,

Go to miata.net and look at the service bulletin for 2000 & 2001 engines
with EGR problems. The "Garage" section shows & tells you how to clean
the intake manifold.

Bruce Bing '03 LS

This excersize failed. The fault is still active. I've driven a week
or two.

Any one have any other ideas before I take it to the shop?

Joe

battjt wrote:
> I cleaned the whole thing with STP throttle body cleaner, even spraying
> some into the lower half of the intake manifold. It eventually started
> and seems to run fine.
>
> My local mechanic mentioned that there is always a lot of oil in the
> intake, especially of Fords.
>
> Joe