code 12
 

how do i fix a code 12?
egr valve thingy
its an 94 lx. with d15b vtec with p28
i thought only VX has the egr dealy

Re: code 12
 

burp

Re: code 12
 

bump for a real technical problem

Re: code 12
 

Exhuast Gas Recirculation valve.. Hrmmm.. I though the h22a were the only ones that came with that? Best way to bypass it is to just find another obd1 ecu that doesnt require the emissions component. So swap ecus.

Btw I didnt know that the d15b came with egr? is it a jdm d15b with the stock ecu? or a different ecu?

Re: code 12
 

usdm p28. that gives me a 5k rev limit
the motor was already working in another car on a p28
ive tried a p28 that was messed up. and a p06 that doesnt give me a cel but when i get up to 5k rpm i get a hesistant stutter

Re: code 12
 

First try and reset the ecu. Remove your battery negative plug for around 20 secs or the radio fuse underneath your hood. This should clear it of any codes. The egr doesnt really affect performance.. Matter of fact it doesnt effect it at all when its on.. its only to remind you of the emissions crap.

But for it to only let your rev 5k?? thats a problem.

try another obd1 ecu possibly your friends p28 just to make sure. and see how that goes.. if it doesnt get rid of the egr code then come back so we can fix this.

Re: code 12
 

Might also try locating the egr valve if it does exist on that engine and clean it out. Also check vacuum on the hose going to the valve. There should be nothing at cold startup for about fifteen min if memory serves. That would be about the time it goes into obdI closed loop. Then i think you should have 4-6 lbs of vacuum. There is also some electrical things to check but i dont know what pins and the readings you should be looking for. Hope i shed some light on your problems. Let me know wha ends up being your problem

Re: code 12
 

i removed the charcaol canister and plugged the nub on the TB and pointed the gas tank vapor downwards. i did this on my other same exact car. doesnt hurt and doesnt matter. that cant be it. can a realy old cat, clogged up cat make it struggle over 4k rpm?
iv tried 3 dif ecus now. 1 p28 gives me cel and shakes the car no good. other p28 gives me a 5k revlimit and code 12. the p06..isnt vtec, so that sux, and it still struggles to go over 5k. weird. any more suggestions

Re: code 12
 

you need to clean the EGR ports on your intake manifold....i had the same problem on my brothers accord....cleaned em out...and whallahhh....no more codes...

ill get you a diagram momentarily...

Re: code 12
 

Only the D15Z1 engine has an EGR system, which can cause a bunch of engine performance problems when it fails. But you have one of the D15B engines that do not have an EGR system, so I presume you have a P28 ECU for the D15Z1 engine. [Edit: Something's wrong, because I don't think a P28 ECU will look for an EGR. Are you sure that you have a P28 ECU? Might you actually have a P07 ECU?]

http://i267.photobucket.com/albums/i...cture_3252.jpg

By the way, here are rev limits for 5th gen Civic engines:

http://i267.photobucket.com/albums/i...cture_3250.jpg

Re: code 12
 

yea it seems the EGR valve only was on the D15Z1. sounds like youve got a tricky one!

Re: code 12
 

where is the egr valve thingy. is that the black box on the back of the block. the 2 p28s say p28 on the sticker and on the ecu plug pin dealy inside. the p06 didnt give me that code but it has no vtec.
so replace the egr valve dealy? where is it at?
so i can just run a catch can?

fyi D15b..the jdm vtec d15

Re: code 12
 

Did the JDM VTEC D15B come with an EGR system? If so, do you have a JDM ECU that would look for an EGR system?

http://i267.photobucket.com/albums/i...cture_3253.jpg

http://i267.photobucket.com/albums/i...cture_3254.jpg

Re: code 12
 

no jdm ecu. the guy that had it in a 93 dx coupe had it working fine, i drove it and it was nice. he sold sum guy the motor and ended up in this car and i got the car by trading the truck. il ask the original owner to check this thread. thanx Ron
maybe i have to pull or cut a certain pin in the harness that goes to the ecu?

Re: code 12
 

I don't know. I am perplexed that a P28 ECU would throw an EGR code. Maybe someone else can explain this to us?

Re: code 12
 

is it possible that his code 12, is not a code 12.

maybe he read the code incorrectly.


ive also seen codes get thrown that dont pertain to a vehicle, or at all.

had an SRS system on an accord throw a code that didnt even exist

possibly he has a code 3 - map sensor 3 quick blinks, he interpreted the first one as a long blink

or a code 21 - vtec spool solenoid valve. 2 long blinks and 1 short one

Re: code 12
 

I wonder if somehow the wires for VTEC got put in wrong in the ECU harness. Might want to double check that, here's a diagram for the wiring.
http://www.superhonda.com/forum/f55/...inouts-217405/

A11 and D12 would go to the EGR valve. If nothing else, maybe you could trick the ECU into thinking there is one. The P28 came ouf of a 94 EX coupe that was NEVER modified, the engine didn't have an EGR and the 94 LX didn't have an EGR since it had a D15B7

Re: code 12
 

I asked Jesse this and he said he got a fast blink and two slow ones.

Re: code 12
 

i dont think they wires would be in the wrong place from the factory unless the OP did his own wiring.

still, the p28 shouldn't show a code 12 as RonJ said

Re: code 12
 

that would be a code 1 Oxygen sensor

and a code 20

electronic load detector.

looks like he needs a new fuse box (under hood)

and a new oxygen sensor


i would reset the ecu (pull the under hood 7.5 amp fuse for a couple mins)

and drive the car

when the light comes back on check the codes again.

if he had a code 12 it would be

1 long blink and 2 short ones.

Re: code 12
 

...the 94 LX didn't come prewired.

Re: code 12
 

Wait, woops, that is what he said in a text. A long blink and 2 short blinks.

Re: code 12
 

no 1 slow blink.. then 2 fast blinks

Re: code 12
 

i am aware of that.

the op didnt state which vehicle chassis he had.


i just noticed you did in your first post

Re: code 12
 

well then go to the ecu and make sure you wired in vtec correctly.

i still have a hard time believing that p28 shows a code 12.

do you have another ECU to try?