Okay guys this is my last Hail Mary before I decide to sell it because I am stumped. I have a 1993 Honda Civic cx hatchback car is completely bone stock only after market thing is a mono steering wheel put on by the previous owner. While driving one day I pulled into a parking spot and the car randomly died and that’s when I noticed smoke from around the ecu and car wouldn’t start back. Towed the car back to the shop went through troubleshooting found the ecu burned like another member on here in his post I believe his name is “pschum” and a under hood fuse #47 I believe the 7.5 fuse was popped. After ordering a new ecu running through all the wires checking the grounds fuses firewall and back. I found nothing hooked up the new ecu and it fired right up. Kill it let it run for a bit kill it again figure everything’s good decide to take it out for a drive. Get about 2-3 miles down the road car bogs down and dies a lot like how a car does when I runs out of fuel even tho it has fuel in the tank. Pull over kill it start it again fires right up so I try to get it back to the shop before it acts up again get about 2-300 feet dead won’t start back up. Pulled the main relay thinking that it could be that problem like in the other forum walk to the nearest O’reileys and get a new one still nothing. Went through the usual troubleshooting like the Haynes book recommends pulled the fuel line pulled the relay jumped the 5-7 wire and the fuel pump kicks on sprays out some fuel and is reading 12.35 volts. Went through the wires on the fuel relay as well with a multimeter and was able to get 12.35 on all except for the green/yellow wire which I was reading from a post on reddit from “walkers” that the green yellow wire is to the ecm. What should be my next step be?

 

When you turn key on but don't crank, does the CEL come on then go out? The fuel pump should also run while the CEL is on and stop when it goes out. This indicates that the ECU is at least booting up, and that the ECU through the main relay has control of the fuel pump.

If that passes you'd go on to check fuel flow by disconnecting the return line. Loosening the bolt on the filter doesn't tell you if there's enough pressure to open the regulator. Everybody on youtube seems to do it that way because well there's a lot of bad advice on youtube.

 

The CEL light stays on when the key is turned to the on position. Also the ecu board looks clean no shorts or anything from what I can tell

 

Check whether hood fuse 31 is blown and whether jumping main relay connector pin 1 to pin 7 makes the fuel pump run.

 

Check ECU ground wires.

This probably means your new ECU is bad. It may be possible to fix it with new capacitors.