what the title says.. any ideas? i looked for a previous thread about this but no one has replied to it. if i replace the fuse, and try to crank it, the fuel pump comes on for 1/2 a second and goes off, resulting in the ecu fuse blown.

 

Does the fuse blow once you try to crank? If so, you may have a wire grounding out somewhere.

 

What kinda car? year make model? what fuse blows? inside drivers compartment or underhood fuse/relay box?

 

What have you done to the car lately have you removed any grounds?

 

check your o2 wires

 

its a 94 civic CX HB.. jdm b16 with itr trans. stock d series wiring harness. have had this swap for 6 years now.. never had this problem. last thing i did was an oil change and new internals on transmission. the ecu fuse under the hood. blows. like everytime u turn the fuel pump on. it blows.

i took the dash out and wiring harness. checked it for shorts and what not. its fine. so i put it back in, and it doesnt blow the fuse anymore. (so whatever that was i fixed it)
but now the car doesnt crank. it'll prime the fuel pump but wont crank the car.. its like the battery is dead, but i tested the battery with the honda battery diagnosis tester and it tested out good. at 410 CCA. any help would greatly be appricated.

 

sounds like short in the main relay to me.

 

How's your dizzy, is it getting spark? Have you tried a different main relay? CEL goes away after fuel pump primes correct?

 

Check your grounds to the thermostat housing and the ground on the tranny. If they are tight remove them and clean the contacts and reconnect.

 

i had this EXACT problem on my gsr eg in the middle of a canyon run. then it happened again the next day. then it just went away i guess, hasnt happened since. gl!

 

Same problem with my moms 96 TL too. was the main relay.

 

take your relay out and check to see if it's working theres a thread at the top of the board that has how to tell

 

well it ran fine since i had the problem. and now, the green and black wire on the main fuel relay caught on fire. luckily it stopped before hitting the actual harness.. i dont know what happened.. again, i checked the ENTIRE harness, and nothing is touching. HELP???

 

yall really think it could be the main fuel relay going out? like is blowing the ecu fuse, a sign of it going out? or about to go out whatever?

 

no as soon as the fuse blows, the cel stays on.

 

in the diagram below, which specific wire(s) connected to the main relay burned:

 

it looks green and black. but from the diagram i guess number 5.

 

Number 5 connects to fuse 24 under the dash, so it doesn't fit. Can you go double check the color of the burnt wire? This may help pinpoint the problem.

 

im at my girlfriends house right now.. can i pm you my number? im gonna be working on it tomorrow. well this morning haha.

 

another thing that i remembered.. my main fuel relay harness has more than 7 wires going to the clip. now there are only 7 pins. but what im saying is there are a few 2 or 3 wires going into 1 pin.

 

Tomorrow, check whether disconnecting the connectors to all four fuel injectors, the IACV, the EVAP purge cut off solenoid valve, and the O2 sensor prevent fuse 31 under the hood from blowing.

Of course, carefully tape up all the burned wires before doing the above test.

 

i dont have any evap thing. if i unplug the fuel pump ground it doesnt blow the fuse. or if i unplug the light gray connector thats right behind the hole before entering the engine bay, the fuse doesnt blow.

 

What specific fuse is blowing under the hood?

 

number 31. ecu fuse. 15a

 

Is either fuse 18 or 24 under the dash blowing?