egvtec

I have a 93 si civic with a b18b swap and it is torquey down in the lower rpm but it feels like its lacking power in upper rpms. And its only getting 25 mpg. There are no CELs 02 isnt throwing any codes and i just did new ngk plugs, wires, fuel filter, battery, dist cap rotor. Has a 3 inch exhaust and no cat but i dont think that would cause the problem. Timing belt timing is dead on, dist is slightly retarded. Anyone got an idea? I also sealed the o ring on the map sensor today cause sometimes when that doesnt seal well it can cause bad millage. Thanks for reading

egvtec

I just pulled my sparkplugs for a read and they are white indicating the motor is running lean... Figure that out combined with 25 mpg at most....

94CivicSi

iTrader: (1)

Stock P75/PR4 ECU?

egvtec

Yes stock P75 ecu, fuel pressure at 38psi at idle, so heres the noticable things, no CELs, white plugs, 25mpg, runs fine but seems little sluggish higher rpms, dist timing slightly retarded, i just think that it being lean but getting bad gas millage is wierd.

94CivicSi

iTrader: (1)

Possibly pinhole leak somewhere when rail pressures increase? A friend of mine had some corrosion on the top of the hard delivery line that runs under his '95 Integra from years of road salt. It wasn't bad enough drip at idle, but you could see that the hard line had a "wet spot" where the leak was.

I would throw out early fuel pump failure, but that wouldn't explain a drop in mileage.

egvtec

Yeah it unusual that its lean with bad milage. I just bought the car a few months ago and have been fixing all the problems with it, and im down to this and shes perfect. the car does have obd0 injectors with a resistor box on it for some reason but i dont think that would be causing any problems cause the plugs look the same in all 4 cylinders indicating that the injectors are working even and properly. It has a vtec harness and they had the vtec spool plug swapped with the water temp sensor but i fixed that and it actually starts now when its cold, before it would take 5-6 trys but thats fixed. It didnt even have a check engine bulb when i got it lol

egvtec

I know someone has had this problem before, its gonna take the right person to read and say i had that happen and it was this...

egvtec

Does anyone know if this could be a water temp sensor?