hello

we have been struggling with my son's civic problem.
she just died 6 days ago. he described it like as if she ran out of gas.
1. gas is good. fuel gushes out of fuel filter and spark plugs smell of gas.
2. she cranks fine, there is no spark.
3. we had distributor replaced with a new, not even reman-d, yesterday. no spark. new. igniter, coil, everything, including cap and rotor.
4. coil has 12 volts to it. we even had spark plug wire directly to coil tower, no spark.
5. mil does not blink at all.
6. all fuses are good.
7. with key turned to dash on, only check engine ans some red light come up. i am not sure if ALL of the dash lights are supposed to be up.
8. belt is not ripped, as rotor turns as camshaft turns.

we ran out of ideas and don't really want to keep replacing parts on a guess. there's really nothing else to replace. car has been very good and reliable. it just died.

 

Check the ground wires on the thermostat housing.

It is possible to blow the coil (even a new one, I would assume) by firing it into an open circuit, such as having a spark plug wire disconnected. Generally if this is the case you would still have weak yellow sparks testing directly at the coil tower.

If you turn the key on but don't crank, the CEL should come on for 2 seconds then go out. If it never comes on or if it doesn't go out, there is a problem with the ECM-- either a dead ECM or it is not receiving power and ground. CEL not going out could also be the main relay but usually the fuel pump also won't run in that case.

The red oil and battery lights should come on and stay on wit the key on but engine not running. If they go out instantly when you turn the key to crank, the ignition switch could be bad. You can test this further by pulling the hand brake up then the brake warning should also stay on all the time, including while cranking. Those lights are on the same circuit that powers the coil.

 

thank you mk
basically, we do have it narrowed down to ecm. not main relay, as fuel pumps fine and starter cranks fine.
yes, ce and oil lights come up and stay. no other light.
we have 0.11V between map + and thermostat black wire. which is supposed to be ecm ground you mentioned. internet says it must be 5V.
hence, it's either dead ecm or it's getting no power under condition that fuse is good.
here's my theory. read it somewhere. spark plugs were never changed since he owned the car, which is 4 yrs. neither were plug wires, rotor, distributor cap and other ignition components.
when i removed the cap, terminals in it were GREEN from oxidation and had about a millimeter thick layer of carbon buildup. so did rotor. basically, a powerful resistor. some guy on honda site says that if you have something like this in the circuit, electricity has to go somewhere, so it either blows the coil, or ignitor, or ecm. backfiring effect. i am amazed that car ran with all that buildup at all. and still gave him 38mpg.
we are expecting a guy today with working ecm to test and see what happens.

 

ok, here's update

1. hand brake light does NOT come up.
2. i have removed and cleaned ground for ecm on thermostat. we have improvement, now it shows 0.14/17V.

 

1. it is not computer. we just tried diff one
2. brake red light comes up only when starter cranks, even with handbrake handle down.
3. we took switch apart. contacts are slightly worn out, but ok. there is no 12V anywhere on any of the contacts. we had, at some point, 1.6V and then it plummeted down to 0.17 and stayed there no matter what contacts we tried.
4. here's the thing. he has aftermarket alarm installed. it's plugged directly into yellow 12V wire that goes to switch. thought is - kill switch tripped in alarm and killed power to the ignition. we'll yank alarm out saturday morning, no need for it anyway.

 

The alarm is suspect. Definitely disable it.

When you turn the key to ON(II), do you hear the fuel pump prime for 2 seconds and do you measure battery voltage at the Blk/Yel wire attached to the coil and igniter unit inside the distributor?

Have you verified that the timing belt did not snap?

 

1. fuel is good. gushes out of fuel filter and plugs smell of gas
2. THERE IS NO SPARK
3. MAP ecm + to ecm negative on thermostat reads 0.11 V, not 5V.
4. coil has 12V to it with key turned on; there is no spark even durectly off coil tower.
5. on the dash, there's only continuous CE light and low oil pressure light. red brake light comes up only when starter cranks.
6. on any given terminals on ignition switch there's 0.16V at the best, even with switch to ON. including yellow power wire.
7. one of the alarm wires is directly spliced into yellow power wire that goes to switch.
was too cold to mess with it yesterday night. we left it all till saturday, so good guess will be appreciable.
yes, we do have the whole entire NEW distributor, not remanif-d one, installed.

 

I think the alarm is interrupting the ignition power. Bypass it. Also make sure the underhood grounds are good. There should be zero volts from the thermostat housing wires to the battery (-) post.

Could also be a short in the sensor circuit, or the ECU is not getting power. You should have 5 volts at the MAP sensor whenever the key on. This power is supplied from the ECU to the sensors. Test the power and ground pins at the ECU to make sure they are powered and grounded.

 

1. there are 4 wires on thermostat housing. 2 black ones?
2. Could also be a short in the sensor circuit which sensor?
3. Test the power and ground pins at the ECU to make sure they are powered and grounded how do i know which pins? wiring diagram we have from haynes ain't worth a flip, it's "typical".

thank you. i am away from the car till sunday, but will do all the tests. collecting useful info like this is of great help. it has been a very, very good car for 4 yrs, i do not wish to give up on it easy.

 

here is the link to the ecu pinouts,

https://www.hondacivicforum.com/foru...ad.php?t=73241