EGR valve cleaning

[ryuu]

Last week for about ½ a day the CEL was on and was off the next morning, scanner showed P0402 so from what I have read I need to clean the EGR valve & intake manifold. Car has about 145,000 miles and I don’t know much about the history.
I haven’t worked on a car in well over 10 years so figure this is a good place to start.
Know to use anti-seize and throttle body cleaner, after that any and all suggestions are welcome.

Also I always liked to use new gaskets when putting things together, would a new gasket be waste in this case? Should I use any RTV with new or old gasket? If so any suggestions on color?
Does the miata shop by TMS sale new parts (gaskets)?

When I bought the car the guy said the CEL came on, the dealer said it needed a new cat and they cleared the CEL so I may be barking up the wrong tree but it’s a good starting point.

Thanks for any help.
sam

[motorollow]

Gagkwong knows all about CEL codes on 1999 cars. Maybe he will chime in on this post.

[sammm]

What year is your car?

[ryuu]

What year is your car?

Sorry, it's a 99.

[POS Racing]

Pretty common problem with the '99's here is a nice write-up with pictures - http://www.miata.net/garage/manifold/index.html

[sammm]

Pretty common problem with the '99's here is a nice write-up with pictures - http://www.miata.net/garage/manifold/index.html

Steps 15-18 are the most important IMHO...run some weed-eater line or something thru that passage while cleaning and get all the crap out of it.

[ryuu]

Thanks guys.

Steps 15-18 are the most important IMHO...run some weed-eater line or something thru that passage while cleaning and get all the crap out of it.

This is exactly what I’m hoping for, tips that only come from experience. Took 3 tries to fix the window so for this I'm asking first.

[EricJ]

When I did mine, I found I had to swap the location of one of the vacuum lines on the intake manifold. There is one very low behind the throttle body. I swapped it with the unused one on top of the manifold and used the cap to cap the lower one. I'll try and get a picture this evening.

I cleaned the intake manifold, throttle body, EGR valve and the idle air control valve while having the upper manifold off. I did not use a new gasket as the old one was metal.

[ryuu]

When I did mine, I found I had to swap the location of one of the vacuum lines on the intake manifold. There is one very low behind the throttle body. I swapped it with the unused one on top of the manifold and used the cap to cap the lower one. I'll try and get a picture this evening.

I cleaned the intake manifold, throttle body, EGR valve and the idle air control valve while having the upper manifold off. I did not use a new gasket as the old one was metal.

Thanksfor the help, I found a picture ... google is my friend.

This is how I remember things like this going ...
I remove the egr valve and 1/2 the gasket is on the valve and 1/2 on the engine so i scrape the old one off
Run to the miata dealer, it's Sat so they are busy, finally my turn and they don't have what I need in stock... next dealer same story so they order one
Car is down for 2 weeks, new gasket arrives and I cannot hold the gasket in place while trying to put the part on ...
run to walmart for some sealant, stick the gasket to the part and install
If I'm really lucky I don't round any bolt heads, strip threads or break a bolt.

[sammm]

^That won't happen with these. They are 'permanent' gaskets...not cork, felt, etc.

[EricJ]

Here is the picture of the Vacuum hose re-route. Remove the hose from the lower, put it on the upper. Put the cap from the upper on the lower. I think I had to use a little longer hose, but there is a junction in the existing hose to use. Don't break it where the other end of the hose connects ($70 part). But if you do, super glue seems to work.

[ryuu]

Thanks guys, great tips and info.
Between our move shipment (40 ft. container) and Thanksgiving it looks like this will have to wait a couple more weeks.