Hi I performed the code process and received the above codes. I have a 1994 Honda Accord LX 2.2 Engine Automatic Trans 4 cyl. What do these codes mean?
The original code 12 on CEL told me EGR Valve...I changed it and still have that same code pop up.
The D4 Code 18 is new and I need to know what that means in order to repair or replace part. Someone help me out, I have an inspection coming up soon.

Thanks.

 

Look in the DIY section for a thread about cleaning your EGR passageways. Often it's not a bad EGR valve, but it's clogged up EGR passages in the intake manifold.

I don't know about the AT.

 

Google T2T013.pdf for the procedure for a 94-97 accord. Its on the last two pages.

There is no code 18 for the transmission, so you definitely have a code 8. The other code is either 1 or 10, depending on how long that first blink is.

If it is code 1 and 8, then there is a problem with the shift and lockup solenoids on the transmission.

Check that there is no crud on the electrical connections. You can check the resistance on the solenoids by looking on the shop manual. You can also unbolt the solenoids and clean the screen and solenoids from buildup. Use throttle body cleaner.

The spooner site I posted in the Online Manuals thread in the DIY section has a 94 shop manual that will show you how to diagnose the problems.

 

About the code 12, be sure that as the engine RPM comes up thru 1500-1700 there is vacum going to the EGR valve.
To test for plugged up EGR ports; with the engine warmed up at idle, put your finger under the top of the EGR valve and push the pintle up. The engine should stumble severely or stall if the ports are clear.

 

Oddly enough i checked my codes today and i got code 12 for the cel, and the D4 blinks once pauses and then blinks 8 times. Is this just a coincidence or do these codes normally happen together? My EGR valve itself moved nicely, reminds me of a BOV. I like the idea of checking the passageways by seeing if the engine stalls, i tried looking in them with a flashlight but failed. How important are the shift and lockup solenoids? My tranny seems to shift fine, maybe a little hard when i gun it at times but works fine.

 

The solenoids are used to shift gears or lockup the torque converter.

Check that the electrical connections are clean and have no crud in them. Also, unbolt them and clean out the screen and solenoid of any debris that could clog them up.

Plugged EGR ports are common over time on your accord. You should clean out the EGR ports. Get that pdf I posted earlier. The last two pages show the 94-97 cleaning procedure.

There is a DIY writeup by Hondadude: https://www.hondaaccordforum.com/for...ad.php?t=28456

Also another site with good info on EGR cleaning: http://www.dhost.info/accordinfo/howto/egr.html

 

the shift and tq solenoids they tend to mess up is very commonly with f series honda trannys. You best bet is it clean them and see if things change...b/c they re $250 each from honda. Or go to a pnp if they are bad and just pocket like 4 of them Iv done that many many time to help myself and others with honda trannys.
ANd yes you can have a CEL pop while your D4 pops too. That means you have more than one prob. with your car...one being something with the tranny and the other with your engine....if you need to check your ECU or youtr TCU code I posted a thread in the DIY part of the forum to help you out,