civic no start problem

[kenneth van yperen]

hello out there in this world of civic... I have a request and was wondering if anyone had any direction on where to go next.. I just installed a used engine and transmission in my sons civic and now have a no start situation. I have replaced the distributor three times and the main relay and the under hood fuse box. the crank fluxation sensor, cleaned the ground on the thermostat housing and tried a known good pcm/ecm...

after all that I still have no spark.... any ideas?....

 

[kenneth van yperen]

What engine and ECU?

Does the starter crank the engine?

The engine is factory.. I believe it is a d16y7.. non vtec.. Factory ECU..

Engine cranks ... timing belt is good.. no spark from coil and battery voltage is present.. replaced the distributor three times and still no spark... thinking it may be a harness or ground issue but the wiring checks OK for now opens or shorts...

And the crank fluctuation sensor is not getting a 5 volt reference signal...

 

[kenneth van yperen]

What year Civic?

Does the fuel pump prime?

Any CEL codes?

1998 civic

Fuel pump does prime and no CEL codes

 

[kenneth van yperen]

Ohm test the coil removed from the distributor.

On what wires inside the distributor are you measuring battery voltage?

Tested and tried 3 different distributors.. all within spec..

The black/yellow wires to the coil.. and the wires to the ignitor as well... all have battery voltage ..

 

[kenneth van yperen]

Do all three distributors work on another 96-98 Civic?

It's pretty easy to blow the coil if you are not careful.

How did you check for CEL codes?

Yes all three worked..

Will see if I can get another one..

With a snap-on scanner through the obd II dlc

 

[kenneth van yperen]

With the key in ON(II), what voltage do you measure at the Yel/Grn wire attached to the ICM?

With the distributor cap removed and distributor connector unplugged, does the rotor spin while cranking the engine?

If I remember correctly I got battery voltage... I will have to double check that..

The rotor turns normally.

 

[kenneth van yperen]

hi there... sorry it took so long to reply I finally found some time to test the harness.... with the ecu unplugged the voltage on both connectors read zero voltage

Unplug ECU connector A, and turn the key to ON(II). How does the voltage reading at the Yel/Grn wire connected to the ICM compare to the voltage reading at pin A20 (Yel/Grn wire) in the unplugged ECU connector?

 

[kenneth van yperen]

That's a problem. With key in ON(II), what's the voltage on the Blk/Yel wire attached to the ICM?

with the connectors back up or still disconnected?

 

[kenneth van yperen]

with the connectors back up or still disconnected?

I tested the harness and found battery voltage on the black yellow wire ... and when I tested the harness at the pcm with both connectors hooked up I had battery voltage and with both connectors disconnected I had no voltage.. and the same was with the black yellow wire still had battery voltage

 

[Pingme67]

Check the Ground Wire connected to the thermostat housing.
I chased one like that for hours.

 

[kenneth van yperen]

sorry it took so long to respond .. got busy with life.... lol checked the wire on the coil to the icm and both wires have battery voltage....

 

[kenneth van yperen]

Test the Yel/Grn wire that runs from the igniter unit to the ECU for a short to ground or an open.

if I have battery voltage at the distributor connector ... I would assume there would be no open or short to ground if there is battery voltage... as I tested that wire before and found no faults there as well

 

[kenneth van yperen]

The ECU completely control spark timing. The Yel/Grn wire transmits ECU spark signals to the ICM by grounding ICM voltage.

if the wire strands are slightly broken and not yet broken through would a high resistance and a voltage drop create the issue of no spark?

 

[kenneth van yperen]

checked the ecm for battery voltage with the connector disconnected and reconnected and the same at the distributor and checked the wire for opens and shorts and seems to be ok and checked the power supply from the ignition switch which is also good as no power is lost when the key is turned into the crank position. All related to the Yel/Grn wire in the wiring schematics I have

I tested the Blk/Yel wire as well and still had battery voltage from the coil to the icm

understood if the wire has been chafed or broken outer casing in any section of wiring.. will do a resistance check on the wiring harness to see if the resistance is high

 

[kenneth van yperen]

If you remove the distributor cap, unplug the distributor connector, and crank the engine, does the distributor rotor spin?

distributor rotor turns as I had replaced the timing belt and waterpump while the engine was out.

ok I will get to it when I have some more time as it is too dark in my neck of the woods to get outside and test right now... I will keep you posted on the results as the testing is done

thank you for your time and knowledge in helping me with this issue

 

[kenneth van yperen]

was verified and the rotor does spin