I have a 2004 Honda Civic that i recently added lucas fuel injector cleaner to to improve gas mileage. Well less than 50 miles later the engine loss power on the highway and then stalled. I pulled to the side of the road and the car would crank right up then rev up and stall again. I thought it might be the fuel filter but after researching learned that honda has a lifetime fuel filter? I think? anyways any info would be much appreciated thanks in advance

 

The filter doesn't have a specified replacement interval, but that doesn't mean that it will last the life of the car. It's back at the tank, and I think it can be replaced through an access panel under the back seat.

Measure the fuel pressure with a gauge first to confirm that it is a fuel problem. Also scan the ECU for any trouble codes, it might be a sensor problem instead.

 

I replaced the fuel pump and know thats not the problem. The car still starts and runs good for a second and then cuts out. good spark, no computer error codes. i'm thinking it may be a sensor or electrical problem?

 

main relay? try getting the gas drained and putting fresh gas into it.