CEL Code 12 - EGR Valve - cleaned it but still get CEL - Honda Prelude Forum

sun_dance · 08-31-2011, 09:48 PM

So after living with the CEL code 12 - which would go off everytime I turned off the car and restarted, but would light back up after the car went over 50 mph or so...I decided to go after fixing this thing.

I decided to take off the valve and give it a good cleaning...there was TONS of built up carbon and the vacuum seemed good and I followed the directions here:
How to: Clean your EGR Valve

But after driving the car again on the highway the CEL showed up again

So what are the other things I should be checking? The vacuum lines all look good, in fact far better than the ones I changed out on my Audi, since those were falling apart when I touched them.

Is there something I should focus on to troubleshoot this issue other than what I've already done?

BTW, the car seems to idle and run just fine...no issues whatsoever.

jkoni426 · 09-01-2011, 11:58 AM

did you reset the ecu?

if so, you might have to clean the egr ports as well.

sun_dance · 09-01-2011, 12:16 PM

Yep...I reset the ECU by pulling the 10 Radio fuse and letting it sit for about 4 minutes.

As for EGR port cleaning, I've seen a few writeups, but before I do those I'm going to check around the EGR control solenoid valve and see if there's not a "fix" in there somewhere...

EGR port cleaning

sun_dance · 09-01-2011, 12:22 PM

Also for EGR cleaning, my problem is that I have an H22A1 intake manifold, so the ports are welded over. How should I go about cleaning the ports?

They look like th following: http://i66.photobucket.com/albums/h2...r/6c0c7f79.jpg

usmcmarc · 09-02-2011, 12:01 PM

Ummmmm, I think your screwed..dont know how you will clean those ports...since you have it off the engine I would spray tons of carb cleaner in the square EGR port so it will run down the channels..let it sit for a few min and shoot compressed air in there ..maybe find a flexible rod with wire bristle (EGR Port Cleaning kit) and try to feed it thru that port into the channel best you can.
Just keep soaking it and cleaning it over and over.
Maybe even tape off the intake ports and fill the whole thing with cleaner and let it soak...just turn it so the cleaner sits only in the lower end of the manifold?

Is it common to weld over the ports like that?

zfinatic · 09-02-2011, 12:34 PM

ive never seen the ports welded like that....id get another intake mani.

pacificarage · 09-16-2011, 05:44 PM

You might check to see if any of the vacuum lines are crossed or disconnected. Mine had two of the lines crossed from the previous owner and it caused the CEL to come on at about 50 mph as well. If the line has a leak, I'd say it'll do the same. Just a thought.

Also, the code will throw if the solenoid is bad, but not likely.

power3dbyhonda · 09-23-2011, 09:26 AM

I had this on my F22A1. I tried cleaning it with no luck. Sold the car and ended up buying it back. The guy I sold it to said he soaked it in ATF and got the code to go away. Good luck. A new EGR valve is expensive

sun_dance · 09-23-2011, 04:29 PM

ATF?? Automatic transmission fluid?? How would that help?

power3dbyhonda · 09-27-2011, 01:27 PM

Dunno, but my light's not on anymore.

sun_dance · 12-19-2011, 09:59 PM

Hi, someone mentioned about vacuum lines being crossed...can you tell me which vacuum lines you were talking about?

pacificarage · 12-23-2011, 02:08 PM

Quote:

Originally Posted by sun_dance

Hi, someone mentioned about vacuum lines being crossed...can you tell me which vacuum lines you were talking about?

Make sure everything is plugged into the right spot.