Dirty Intake Manifold

[harley]

I got the infamous NB P0402 CEL about a week ago and finally got around to cleaning the top half of the intake manifold and it was diiiiiiiiirty. The lower half is also pretty dirty, was wondering if there is a easy way to clean that instead of taking it off? Seafoam?




hopefully my CEL stays off

[jrj512]

This might help...

http://www.miata.net/garage/manifold/index.html

[sammm]

^Pay attention to steps 16-18, and clean that port out thoroughly. I used some weedeater line to break the crud up thru that whole passage.

[harley]

I cleaned the top portion and used about 3-4 cans of throttle body cleaner for that port.

Is there anyway to clean the bottom part of the intake manifold without taking it out?

[Rogue]

No

[EricJ]

Don't forget the vacuum hose re-route.
Move the hose that comes from the bottom of the manifold to the sensor on the fender well from the bottom of the manifold to the unused port on the top. Use the cover/nipple that closed the port on the top on the now unused port on the bottom.

[harley]

Don't forget the vacuum hose re-route.
Move the hose that comes from the bottom of the manifold to the sensor on the fender well from the bottom of the manifold to the unused port on the top. Use the cover/nipple that closed the port on the top on the now unused port on the bottom.

gonna do that next if the CEL comes back

so far ~60 miles cel free!

[gabkwong]

gonna do that next if the CEL comes back

so far ~60 miles cel free!

It may take a couple of on-off cycle to trigger the cel. Another way to find out earlier is to scan the OBDII checking for pending code.