So for whatever reason the ECU on my 05 Civic VTEC partially died after 225k miles. It suddenly quit outputting a signal to fire the number 1 fuel injector. The reason I am asking if all the fuel injectors fire at the same time is because I have no money or desire to replace and flash the ECU, so I connected the number 1 fuel injector signal wire to the number 2 fuel injector signal wire to fire the number 1 injector. It seems to run fine this way. I am wondering if this is somehow damaging something or causing a problem somehow. Can I run it this way? Is this really any different than it was to fire both injectors at once? Thank you for your help, I do not want to cause problems.

 

Not sure if you mean your car idles fine or if it drives fine but yes it will cause issues. Each injector is timed perfectly by the ecu to release a specific amount of fuel into each cylinder. Cylinder 2 does not have the same injector sequence as cylinder 1. Cheapest way to fix this would be to get a used ECU from a junkyard or ebay and get it reprogrammed for your key.

 

Thanks for the reply. Will it cause damage to the engine, or just not run as well? I do not have a cat to harm, so no problem there. It idles and drives fine.

 

I found your problem.

 

Will running it this way damage the engine, cause P0134 code, reduce power or increase fuel consumption?

 

I need help! I don't know what to do! I bought a junkyard ECU and took it to the Honda dealer to get the ECU flashed, and they said that it wouldn't flash and they didn't know why. They were very friendly, and they said that maybe the ECU that I brought them may have something wrong with it, so if I bring them another one they will try 1 more time. I exchanged the ECU at the junkyard that I bought it at for another one and had the Honda dealer try to flash that one. That one wouldn't flash either. What would cause these ECUs to not flash and what do I do about this? Thank you!

 

When you say "get the ECU flashed"... what EXACTLY are you trying to get done ??? Year/model would be helpful. If this is an Immobilizer issue... then your dealership is the likely problem.

 

It is a 2005 Civic LX that I put a VTEC motor in. What I mean by getting it flashed is the immobilizer. The car won't start with new ECU because the immobilizer light flashes and it won't get fuel or spark. I took the glovebox out and pulled the ECU out and reconnected the connectors before I left to drive it to the dealer with the old ECU and gave them the new ECU to flash. They took the car back and about 1 hour later they drove the car back out and said that the immobilizer won't flash. Same with the second ECU. $100 down the drain. I'm not sure what would cause this. I almost wonder if the dealer didn't even bother to try flashing it and just said it wouldn't flash to get more money out of me for diagnostics. He thinks that there is a wiring problem. He said that if I wanted them to find and fix the issue, it would be $200-$300 for electrical diagnostics. What should I do? Thanks.

 

How did you determine this?

They do not fire at the same time. I doubt it runs "fine", At the very least youll be introducing raw fuel into the oil,as well as contaminating your cat.

 

The engine actually does run really well. It starts great, idles great, accelerates great and does not misfire. The only thing that's not great is the gas mileage. It's notbad, but it's only getting around 30 MPG on the highway. I don't have a cat to destroy, so that's not a concern. Another question- Since this setup is apparently causing fuel to get into the oil, would the engine be better off if I unplug the fuel injector and ignition coil for that cylinder while I save up to get an ECU? I will unfortunately have to drive the car for at least a few more months before I will be able to afford to get an ECU and have Honda flash it. Thanks

 

30mpg is awesome to get on a 2005 225K civic. Take it and be done. ECU doesn't need to be replaced.