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EGR Tube diameter?

10-08-2009, 07:39 PM
I am looking at buying a LONG bottle brush to snake through the EGR tube that goes from the valve into the intake manifold.

I don't know the diameter of the tube and hope someone here does so I can purchase the proper brush.

My plan is to cap off the tube, have seafoam fill the tube, let it sit for a few hours (or even overnight), then attach the bottle brush to my drill and basically snake the sucker clean.

I can suck the dirty seafoam/carbon mix out from the top so it doesn't get into the manifold.

Hope to hear from someone in the know!

10-09-2009, 01:01 AM
If the tube is visible than take an open end wrench and size it up. Whatever wrench fits the best over the tube is the size of the tube.

10-10-2009, 01:02 PM
soak in the seafoam and blow it out the exhaust with compressed air

10-17-2009, 12:06 PM
I also fought with the EGR low flow check engine light. I used sea foam,carb cleaner and everything I could think of but no luck. The egr passage was not totally blocked so the sea foam would suck in but I didnt know that the carbon was so hard it wasnt doing nothing for it.I also assumed that since the sea foam was being sucked in that the port was clear. I lived with the check engine light for over 5 years, replacing the EGR valve 3 times and cleaning more times than I care to count. I finally got tired of the light so I was determined to get this fixed. I took the intake apart to the throttle body butterflies and held them open with a wire. There I could see the egr port. The port is approx. 3/8 hole and mine was almost completely blocked.The carbon build up was so hard in that hole that I had to use a piece of clothes hanger with a point filed on it to bust it up. I was so happy to possibly have a fix for this! I got it back together and cleared the light and been check engine light free for 3 weeks. The longest since I have owned it!

99 Fronty
10-18-2009, 07:43 PM
I'm not sure a bottle brush will work. The tube is cast into the manifold at the rear and the passage does a few sharp bends after that up to the EGR valve. You will probably end up just mashing everything into this section.

Everybody has a technique I suppose. In my case I removed the EGR valve and the throttle body. I pushed a length of clear plastic hose over the end of the EGR tube. Hose was 10mm I think which sounds about right, someone else said the tube was 3/8 inside. You might have to lever the tube sideways a little to get the hose on as it is pressed against the manifold at the end.

I then raised the end of the hose and poured a solvent in slowly until it overflowed out the EGR valve port. I used petrol (gasoline) because as a solvent you can't beat it. I left it a few hours and then used compressed air on the EGR port to blast it all out. The hose directs all the mess away from the manifold but the first time I managed to wear sooty crud all over me and the car, you get better with practice. Do this as many times as it takes.

This assumes you still have some kind of passage-way through the tube for the solvent and air. If not you might have to try the coat-hanger first.



10-29-2009, 01:44 AM
Here's my followup:

Ended up taking the throttle body off and using a bottle brush which I was able to get it about 2.5-inches up the tube. By the time I was done, the tube was silver colored again and the SeaFoam I was pouring in from the valve end came out without a trace of black on the other end.

When I put it all back together, it was noticeably better and my mileage increased. Then one morning...rough again. The EGR valve solenoid was finally shot. It was the original (2000) and had been cleaned countless times.

I plunked down the $70 for a factory new Delphi EGR valve and installed it, she deserved it after close to 10-years.

Idles at 500-rpm beautifully. Mileage has increased and power seems to be better, too. Should have done this years ago.

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