1992 Civic VX - Cleaning EGR ports

[Crazy88]

I have a '92 VX. It runs fine, but given that it is 20 years old, I decided to pull off the intake and do some cleaning.

I'd like to clean the EGR ports, but I've never done it on one of these cars. It apparently has some welds that need to be drilled out. Has anyone done a write-up on this? I'd like to find some very clear instructions before I start drilling holes in my intake.

[Crazy88]

Oops. I decided to search for this AFTER I made the thread. Apparently I'm not the only one who has dealed with this.

[cbaber]

Welds that need to be drilled? No way. Its the thing sitting by your valve cover. Take it off (2 bolts) and notice how much black gunk is lodged in the ports. I took some carb cleaner and went to work on the actual valve itself and cleaned out the head a little bit.

I have a 98 civic HX (similar engine) and my check engine light was on for EGR valve flow problems. After cleaning it out and letting it sit for a few hours I started it up and the CEL went away.

While you are cleaning things, take the IACV off the back of the intake manifold and clean it also. This is another area where crap builds up and can cause some idle problems if it gets too bad. Good luck.

[Crazy88]

Originally Posted by cbaber

Welds that need to be drilled? No way. Its the thing sitting by your valve cover. Take it off (2 bolts) and notice how much black gunk is lodged in the ports. I took some carb cleaner and went to work on the actual valve itself and cleaned out the head a little bit.

I have a 98 civic HX (similar engine) and my check engine light was on for EGR valve flow problems. After cleaning it out and letting it sit for a few hours I started it up and the CEL went away.

While you are cleaning things, take the IACV off the back of the intake manifold and clean it also. This is another area where crap builds up and can cause some idle problems if it gets too bad. Good luck.

I wasn't referring to just the two holes under the EGR valve. There is a passage that runs from the EGR to all four intake runners. It is in there that the carbon causes a blockage.

Anyway, I was able to clean it out without having to drill out the plugs. I just removed and stripped down the intake and soaked it in a bucket of parts cleaner for a few days. Then I poured some Seafoam into the EGR port and watched it run out all four runners.

[some_other_dave]

Is it back together yet? Any results to report from the cleaning?

-soD

[Crazy88]

Originally Posted by some_other_dave

Is it back together yet? Any results to report from the cleaning?

-soD

I'll be putting it back together on Saturday. I didn't really have running problems, except for an occasional pinging.

Given that my car is 20 years old I thought it was a good idea to pull the intake just to clean it out and replace all the little coolant hoses and vacuum lines running to it.

There was some carbon built up in the EGR passages but not enough to plug it. I cleaned out what was in it. Also, the runners get coated with black crud. It takes some scrubbing to get them clean, but the inside of my intake looks like new now.

Also, the PCV system on this car is way easier to get at with the intake removed. There is a rubber piece that pushes into the bottom of the intake and goes down to the breather box on the back of the engine. That rubber piece was as hard as a rock on my car and it snapped like a dry twig when I touched it. I got a new one from Honda ($8).

There are also two small coolant hoses that run to the oil cooler on the back of the engine that are way easier to replace with the intake removed.

I also replaced all gaskets (intake, throttle body, EGR) and the o-rings for the fuel injectors. I've also cleaned up the outside of the intake and all the parts around it so it will look nice reinstalled.

I don't expect the car to run a hell of a lot better than it did before, but I expect the work I did to keep it running good for a long time.

[Crazy88]

Here are some pics of the intake after cleaning it and putting it back together.........

[Crazy88]

In the bottom pic you can see the rubber line that sticks into the under side of the intake and runs to the PCV valve the goes into the breather box on the back of the engine.

It isn't actually a valve per se, it's actually an orifice tube that is always open. It allows a small amount of air to pass into the intake at all times.

The four runners were all gunked up with black crud. After soaking the whole intake in parts cleaner for a few days, then going through it with a pipe brush, it is immaculate. The gunk is from blow by gasses that are drawn in through the intake hose that connects to the valve cover.

There was also a lot of crud built up where the injectors stick into the intake.

After reinstalling it, my idle was a high (1800 RPM). After checking and rechecking everything for possible vacuum leaks and not finding any, I adjusted the idle at the idle screw on the front side of the throttle body. I also had to make a small adjustment to the screw that acts as a stop for the throttle (the part the throttle cable wraps around).

It's running perfect now, and a bit smoother than it did before the cleaning. Throttle response also feels better, the engine seems more willing to rev up.


If you intend to do this to your car plan on getting: intake manifold gasket, EGR gasket, throttle body gasket, injector o-ring kit x4, IAC gasket, and probably the PCV hose that goes under the intake. There are also multiple coolant hoses running to the throttle body and IAC motor. Also, with the intake off it is way easier to get at the four coolant hoses on the back of the engine if they need replacement.

[SiVX]

Have you seen much of a FE improvement?

[SiVX]

Question: I have seen others tap out the welds and use a bolt ro plug them afterwards so they could possibly remove bolts in future and wire brush clean the intake without having to take it off. Any ideas on this? Pros vs cons? Seems like a good idea to me to make future maintenence easier.