dr_g

Guys,

As I said in a previous post I am getting an engine error code 12 (1994 2.2 VTEC).

I have a workshop manual, so I started doing the EGR diagnostic flowchart. I got to the stage where it said 'connect the test harness' which of course I dont have. The end of the flowchart results in either replacement of the EGR, replacement of the ECU or a broken wire. Basically, with the engine running, the solenoid valve works when you manually put 12 v accross it, and when it switches it immediately gives vacuum at the EGR hose. The EGR itself operates when I manually put vacuum in the hose, although it did seem a bit clunky at first. The sensor on top has 5volts between the two wires.

What do I do now? I hope to god its not the ECU. I doubt very much its a broken wire. The car runs fine most of the time with the engine light on, although I do notice some flat spots occasionally, just after changing gear.

Question: Can anyone point me in the right direction of a 'how to' for removal and stripping and cleaning of the EGR valve?? Any advice would be, as always, very much appreciated.

Cheers,

Garth.

Acidcrakker

You can just disconnect the ERG harness from the EGR valve and let it hang. You will throw a code from time to time, but you dont need an egr.

EGR block off plate is on ebay for like 10 bucks

also to delete the EGR permenatly, you will need a tuning system that allows you to turn it on and off

dr_g

Well I got the EGR valve off using a modded 3/8" short extension. I ground it locally to about 1/2 its original diameter in order for it to clear the crimped flange on the valve body. Came straight off after a bit of effort. Using a standard 3/8" extension caused the socket to tilt over and was mashing the nuts. They were tight!

The EGR was cruddy. It is clean now and works smoothly under vacuum, so fingers crossed. I have a feeling in my bones it isnt going to solve the 12 error code though. Might need to clean out the ports too.

BTW this 12 code came on about 100 miles after running a can of fuel injector cleaner through the engine. Could this be the cause? It's never done it before in 120,000 miles of running.

Cheers,

Garth.

kulrevon

In obd1 which is what you have. The computer looked for two things from the egr. 1 is if its plugged in which means if the wires complete the circuit. 2 is if the egr valves moves up and down.

So with that being said. If the egr valve is clogged enough not to let it move up and down that will throw a code. So clean it (by hand. the fuel injector cleaner might have dislodged something and got the egr valve stuck). And the only other thing is to make sure the egr has continuity and the computer sees it.

dr_g

O.K.

I cleaned it, put it all back together and took it for a run of about 30 minutes: motorway, traffic and let it idle for 5 mins or so. No light! Thanks for the advice.

One thing I noticed was that on my manifold, the EGR 'plugs' that I have read so much about seem to be welded up on mine, so there is no way I can get to the passages. It looks too professional a job to be non-standard. Any comments? It's a UK spec rhd car.

Also, I've noticed if I kill the engine when hot, and immediately try to start it, it sometimes doesnt start, just splutters and dies. Sometimes never catches. It did it today. Any ideas?

Cheers,

Garth.

Cheers,

Garth.

Acidcrakker

Yeah you have to Port and Tap the ports on the IM. Take the IM off the Engine to do this.

There is a write up somewhere here on the exact specifics.

dr_g

So are are you saying that as standard there are no plugs - just welds?

Cheers,

Garth.

Acidcrakker

yes for most models. I do believe that honda started making the EGR ports already ported on OBD 2 model engines. Not sure about that

dr_g

I just checked some old detail photos of my previous car - a '93 Prelude 2.3i (great car, but cracked its head in half at 100,000 miles). It has identical welded holes on top of the manifold, just like my current '94 vtec. I would have thought Honda would have made the plugs easily removable rather than impossible. Is it a good idea to spray some kind of solvent in the manifold rail, via the EGR holes?? Would this dissolve some of the carbon??

I will see how it goes with the engine light before removing the manifold.

BTW is there a list of "how to's" on this forum (or anywhere). I think I need to re-solder some relays in my 4ws computer, and also change the clutch. Both are jobs that I could do with some advice on really.

Cheers,

Garth.

Acidcrakker

I wouldnt spray anything into that manifold.

You can try Sea Foam if you trust it. Id either block off the EGR or clean the whole manifold

dr_g

I'm going to change the clutch this summer, so while I've got the car over the pit I might remove the manifold because from memory of my 2.3, access is easier from underneath for a lot of the nuts and pipes.

I tried disconnecting the EGR completely, but it still gave the 12 code after about 10 minutes running (not surprising if the ECU is looking for a signal). I'm assuming you remove and blank the EGR, but leave it connected to the electrics? Wouldn't this give the incorrect position signal at some point, and cause another engine error light?

Cheers,

Garth.

Acidcrakker

I dont have one. I throw a code for it ever now and then. Nothing that bothers me. When I go to the Dyno shop in a few months, Im just going to have the EGR turned off completly, then the ecu wont bother looking for a signal.