last night i was fixing my vss sensor and after pulling on the plug realized the prior owner had spliced a plug into the car i saw a small spark so i shut the car off and wired in the plu correctly after i was done i tried to start the car and the car wont start it cranks over but does not start i have checked out the ecu fuse its still good also pulled the covers off my ecu (hondata s300) no burnt resistors at that time i tried to hook up the ecu to my laptop and its not getting any power anyone have any ideas that might help

 

Did you already check fuses 18, 31, 32, and 24? It would be wise actually to check all the fuses.

Do you lack both spark and fuel?

 

checked all fuses and even swapped out the mail relay

 

havent had a chance to check fuel but definetly no spark

 

Is the main relay working and receiving power? Is the fuel pump priming?

With respect to the no-spark condition, check whether (1) the distributor connector is receiving battery power and (2) the ground wire on the thermostat housing is tight and not corroded. If those are fine, next focus on the coil and then igniter unit in the distributor.

 

no fuel pump is not even priming i have 3 mail relays have tried swapping out between them still same problem

 

Pump not priming, clean the ecu ground. clean it real good.

On start, ecu sends out a 5V test signal, if test fails, ecu will not send power to fuel pump.

 

took reading from ecu power im not getting any power

 

is that you ryan

 

Ryan's dad.

You need to find out why ecu is not getting power, check that ecu ground. check fuses?

 

ok update just tried the ecu took it out of my freinds car that he drove here to check still nothing what fuses contol the ecu any relays etc... anyone have any other ideas

 

wheres the ecu ground i think i have checked it but i want to make sure

 

Also check fuse 12. This diagram may help:

 

gonna try that now another weird thing my check engine light stays on it dosent turn off after a few seconds like its supposed to

 

ECU gronud is tipically on the thermostat housing bolt.

You have a B series in there right?

On a D it will be two wires crimped on a brass colored square terminal lug that attaches the T-stat housing.

 

got no power on acg yel/blk wire

 

Just to verify. Did you make the voltage measurement with the key turned to ON?

 

You have battery voltage of about 12V right ?

I found on page 1076 of the 98-01 service manual, the G101 which looks like the ecu ground.


I have to leave in a few minutes,

Good Luck.

 

ecu ground on the engine block good i got about 10.41v been messing around with it for awhile cars getting low on power and yes key was on

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybridmath &raquo;</TD></TR><TR><TD CLASS="quote">got no power on acg yel/blk wire</TD></TR></TABLE>

You mean Blk/Yel wire, right? If so, this wire comes from the ignition switch and is protected by fuse 24. If fuse 24 is definitely fine, then your ignition switch may be faulty. Do lights on the dash turn ON with the ignition switch turned to the ON position? If so, the Blk/Yel wire itself may be damaged.

 

lights come on eveything works radio etc....

 

update: i checked everything i could think of and nothing after checking the wiring between the main relay conectors it said something about acg fuse i looked in the fuse box and there was no fuse in it but there was a black block off in it i put a fuse in it and boom car started right up which is weird cause the car never had this fuse problem i am having now is car has a extremely low rev limit and check engine light still does not turn off after key is turn on and left in the acc position anyone have any ideas also the hondata s300 i am running has a green and ed light it stays on the red light and i am not able to datalog at all

 

Congrats on getting past the no-start. Retrieve the CEL code by the jumper wire method:

https://honda-tech.com/zerothread/1901557

 

already tried that one check engine light stays on no blinks at all ive ben working on hondas for the last 10 years and this is really got me stumped

 

I believe the absence of a code indicates a problem with the ECU. Pages 11-32 to 11-34 of the 92-95 Civic service manual (see link) describes the troubleshooting procedure. Some of the tests require a test harness.

http://hondatech.info/downloads/Auto/Manuals/Civic/