Re: Mystery No Start -- Please Help
 

sprog wrote:
> My 1990 Honda Civic 1.5 cranks but will not start. 134k miles. No
> trouble codes on ECU. ECU does give the 1-blink "hello" signal.
> Fuses appear good. Decided to replace starter, which was original.
> No difference. Battery is good. Attempted to start during jump to
> our van -- no difference. Main relay clicks as it should (once at key
> to start, once after check engine light goes off two seconds later,
> once on cranking). Fuel pump whirring noise can be heard with key to
> start position (good). With cover to intake removed, could see and
> smell fuel entering chamber. Starter fluid tried - no effect. I
> suspected ignition might be the problem. Distributor cap, rotor,
> spark plug wires, and plugs were all replaced. Didn't help. Doesn't
> seem to be getting spark. Couldn't get spark from grounded plug
> attached to wire. I measured resistance for both primary and
> secondary in ignition coil -- both were within specs. Wires going to
> ignition coil are receiving battery voltage. Resistances for TDC and
> Crank sensors (within distributor) tested good (Codes 4 and 8).
> Ignition output signal (code 15) also checked out fine. Distributor
> was removed and rotor shaft does turn freely. You can see rotor turn
> while cranking engine. So timing belt is not broken. I suspected the
> igniter (only thing left in distributor) might be the problem, so I
> replaced this. No help (and $70, non-returnable). Anybody have any
> idea what might be causing this?
>

Probably the ignitor or whatever drives it.
Make sure you see 12V on one side of the coil first (common to both
primary and secondary). Also make sure that you measure a low
resistance across the primary of the coil. You'll see a higher
resistance across the primary of the coil.

Electrically, the ignitor switches the primary of the coil to ground
periodically.
To test, you could put a small low current 12V bulb (so we're not
talking about a headlight or tail light - just a radio shack 12V bulb)
between the +12V and the output of the ignitor. (envision hooking it
up across the coil but taking the coil out of the circuit).

If the bulb flashes when cranking, your ignitor is ok.
If not, it will take a little detective work to make sure that you
indeed are getting a periodic input on the ignitor.

Probably 9 times out of 10, your ignitor is bad, though.

Remco

Re: Mystery No Start -- Please Help
 

Remco wrote:
> sprog wrote:
> > My 1990 Honda Civic 1.5 cranks but will not start. 134k miles. No
> > trouble codes on ECU. ECU does give the 1-blink "hello" signal.
> > Fuses appear good. Decided to replace starter, which was original.
> > No difference. Battery is good. Attempted to start during jump to
> > our van -- no difference. Main relay clicks as it should (once at key
> > to start, once after check engine light goes off two seconds later,
> > once on cranking). Fuel pump whirring noise can be heard with key to
> > start position (good). With cover to intake removed, could see and
> > smell fuel entering chamber. Starter fluid tried - no effect. I
> > suspected ignition might be the problem. Distributor cap, rotor,
> > spark plug wires, and plugs were all replaced. Didn't help. Doesn't
> > seem to be getting spark. Couldn't get spark from grounded plug
> > attached to wire. I measured resistance for both primary and
> > secondary in ignition coil -- both were within specs. Wires going to
> > ignition coil are receiving battery voltage. Resistances for TDC and
> > Crank sensors (within distributor) tested good (Codes 4 and 8).
> > Ignition output signal (code 15) also checked out fine. Distributor
> > was removed and rotor shaft does turn freely. You can see rotor turn
> > while cranking engine. So timing belt is not broken. I suspected the
> > igniter (only thing left in distributor) might be the problem, so I
> > replaced this. No help (and $70, non-returnable). Anybody have any
> > idea what might be causing this?
> >
>
> Probably the ignitor or whatever drives it.
> Make sure you see 12V on one side of the coil first (common to both
> primary and secondary). Also make sure that you measure a low
> resistance across the primary of the coil. You'll see a higher
> resistance across the primary of the coil.
>
> Electrically, the ignitor switches the primary of the coil to ground
> periodically.
> To test, you could put a small low current 12V bulb (so we're not
> talking about a headlight or tail light - just a radio shack 12V bulb)
> between the +12V and the output of the ignitor. (envision hooking it
> up across the coil but taking the coil out of the circuit).
>
> If the bulb flashes when cranking, your ignitor is ok.
> If not, it will take a little detective work to make sure that you
> indeed are getting a periodic input on the ignitor.
>
> Probably 9 times out of 10, your ignitor is bad, though.
>
> Remco

Oops -- sorry misunderstood that you had already replaced the ignitor.
Just noticed it after re-reading your post.

Still the method does apply: the bulb would tell you if you are getting
some sort of periodic input to the ignitor and trace it back from
there.