never done this before but I have a 1997 honda civic with a b20b and im trying to chase a problem I can not solve and talking amongst others might help that. But I thought was fuel issue then thought ignition now thinking maybe evap system issue. Ive replaced many of parts now and im still getting the same issue but nothing has just failed. I get stuck on the road for a few minutes and back on the road again. No good help where I am so I've been battling alone at this. But car seams to run good gas mileage has improved with replaced parts but randomly cuts out and sometimes dies and check engine light pops on and im driving 45-70 and i coast in gear seams like the cars still running but no rpm gauge and sometimes snapps out of it and other times I sit. But then its good and then ill stop somewhere and sometimes just won't start for few minutes. Just sits and cranks. And ive noticed my gas tank has been full of air sometimes when I open it not sure if thats on the evap system?
replaced parts.. fuel pump and tank seal. Fuel filter. Pfr aftermarket with a gauge on. Waiting for adapter to fuel rail for that. Ignition control module. Ignition coil. Cap and rotor.

 

Post all CEL codes stored in the ECU, and mention ECU that runs the B20.

 

I'm an old school kinda guy so all this electric stuff to me is learning. What do you mean cel codes?

 

I'm an old school kinda guy so all this electric stuff to me is learning. What do you mean cel codes?

 

Check engine light = CEL

Jump the service connector to watch the CEL blink the codes. Post a video if you don't know how to read the blinking codes.

What ECU/computer (located behind passenger kick panel) is running the B20?

 

How do you jump the connector?

 

 

 

The 2-pin service connector is located above the ECU. Use a wire or paperclip to short the two terminals of the connector. Turn key to ON(II) to watch CEL blink the codes.

Looks like you have an OBD1 ECU for the SOHC D15B7 engine. It looks to be chipped a DOHC B18C1 engine. One of our swap gurus should be able to tell you whether the chip is fully compatible with the DOHC B20B engine.

 

is

Is this right connector?

 

Looks correct.

 

I plugged in paper clip and it didn't do anything different?

 

It should at the bare minimum put the CEL on solid with the key in the on position. If there is a code stored, the CEL will begin blinking with the connector jumpered and the key turned to the on position.

You have what looks likely be a chipped ECU made to run a dohc B18C with the mods listed.

It's possible something in the ECU has gone bad. Kind of common on these 25+ year old ECU's. Capacitors in particular. If you pull the cover plate off that P06 ecu, you might see a blown capacitor or two.

 

The next time the CEL turns on while driving, leave the engine running while you jump the service connector. This should allow you to retrieve the code.

 

I can't remember off hand if cel stays on when it stalls and dies but say just leave the key on park and jump the connector the light should start blinking? And as for the ecu unplugging and opening it up will that reset anything? I know the car has been road tuned when it was built by a pretty good tuner but I dont know alot into this field im learning as I go ive always been more of a carb guy. And not a big computer guy but I do say great help here I wish I got involved long ago! So thank you everyone I just need to find this issue I get decent power for nothing major and was getting great milage. I like to keep things running and this is my hobby just really appreciated the help.

 

And say a compacitor is bad is that something a guy can replace or am I going to be looking into new ecu?

 

Yes

If the CEL turns on without the engine stalling, then also leave the key on and jump the service connector.

The retrieved code(s) may help to diagnose the problem.

This^ would clear any CEL codes stored in the ECU memory.

 

Ok awesome I have a good drive today with it so I'm hoping it doesn't stall but if it does maybe like you said can find an issue because I've been guessing. And I guess at this point my ecu didn't code anything but it did make the cel light solid when I had the paper clip In. So I guess there should be no harm in unplugging the ECU? Just to see if anything is bad?

 

At this stage yes, Since no code is stored, you aren't losing anything unplugging. Then you can unscrew the cover and look to see if anything has popped and burned inside the ECU. A guy can replace capacitors with the right tools. It's not the easiest thing but is doable and isn't overly hard, just a little challenging.

When it stalls and CEL comes on, if you don't turn off the key and you jumper the service connector, hopefully it gives you blink codes.

 

Also verify that the 7.5A hood backup fuse is not blown. If it is, the ECU would not be able to store codes.

 

Ok ill check more into that tomorrow but I drove almost a full tank with the cap cracked just for ***** and giggles and havmt had any issues yet!?

 

Update started working on a new project for work been very long days and I dont drive as far to work now but ive been driving with gas cap cracked and I havnt seen any issues. I just havnt had the time to mess with it and try and get it to act up to check codes but still wanted to say thanks for the help to all