Honda Car Forum

"jim beam" <nospam@example.net> wrote

> despite your main relay test, intermittent no-start usually /is/
> main relay in my experience, especially for a civic/crx this age.
> usually accompanied by a code 16 though.

Like Graham W said, if there's fuel pressure the main relay is fine.
That is how the circuit works.

ThomasE wrote:
> Thank you for your replies
> ? I know how to spray started fluid on a carburetor car but how can I
> spray starter fluid in a fuel injection car, there does not seem to be an
> access point to the air intake.
>
> Thanks for the link to the main relay description. It seems to me that the
> main relay should be ok since I have fuel pressure, so the relay and
> computer are feeding current to the fuel pump correctly (I can also hear
> the fuel pump running for 2 seconds when the ignition is turned on). As
> far as the power to the injectors goes I assume that if the main relay
> were not supplying voltage to the injectors that I would get a code from
> the computer (or will I not? ), but as I said I get no computer codes.

Injector operation (that they ARE operating, that is, not necessarily
that they're operating PROPERLY) is easily checked: crank the car over a
bit, then immediately take a plug out and see if it's wet with gas.

Have you tested the compression?


---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0612-4, 03/25/2006
Tested on: 3/26/2006 9:24:22 AM
avast! - copyright (c) 1988-2005 ALWIL Software.
http://www.avast.com

Burt wrote:
> "jim beam" <nospam@example.net> wrote
>
>
>>despite your main relay test, intermittent no-start usually /is/
>>main relay in my experience, especially for a civic/crx this age.
>>usually accompanied by a code 16 though.
>
>
> Like Graham W said, if there's fuel pressure the main relay is fine.
> That is how the circuit works.
>
er, ok, so when your *intermittent* fault happens to be /not/ evident
when you test, and faulty when you're trying to start, then what? fact:
for this age civic/crx, you're well inside 3 sigma on relay faults.

Burt wrote:
> "jim beam" <nospam@example.net> wrote
>
>
>>when testing spark leads with an old plug, open the gap right up -
>>sparking distance is different at atmospheric pressure vs. cylinder
>>compression pressure.
>
>
> This is pointless if you simply want to check for spark.

no it's not. because it's harder to spark a small gap than a larger one
at atmosphere, you may not see a spark, even if the system is ok.

>
> The correct way to check for a faulty plug or coil output is to
> check the spark jump at the distributor. This is easily done alone.

not on a honda and trying to use a normal plug lead it's not. the
connector is too recessed and the hole too small for the lead to fit.
if you're /not/ using a plug lead, there's too much chance of leakage to
spark reliably, particularly if you're trying to spark on a plug without
the gap opened to work at atmospheric pressure. besides, if the
distributor cap or distributor arm are faulty you need to test
"downstream" of those components.

I have not tested for compression but I have no reason to believe that
anything is wrong with it. The car was working fine then I left it in the
garage for 2 weeks and now it does not start.
I know that the cranckshaft is turning properly, no broken timing belts
etc.

Just to eliminate some things:
Have you tried the cure listed at
http://www.tegger.com/hondafaq/start...s.html#flooded
for flooded cylinders? This may happen with leaky injectors
after the car sits awhile.

I see your comments on your main relay check, but I am still
concerned about whether the pump continues running. You say
fuel pressure is there, but is it continuously there? From
looking at tegger.com's description, I am still suspicious.
See for example the more detailed discussion at

http://www.tegger.com/hondafaq/mainr...mainrelay.html

(Sorry, it's hard to tell exactly what's going on. It's the
price of diagnosing via posts.) If the main relay has never
been replaced or re-soldered, I'd sure be inclined to take
it out and re-solder.

The main relay is such a common problem on older Hondas. My
91 Civic's died in 1999, after about a year of intermittent
no start conditions.

As for codes, the computer and code setoff system are not
very sophisticated on these older Hondas. I do not recall
seeing codes set in the past when people have reported a
no-start problem and re-soldering or replacement of the
relay fixed it.

How old are your ignition wires? Are they OEM?

"ThomasE" <lester12@yahoo.com> wrote
>I have not tested for compression but I have no reason to
>believe that
> anything is wrong with it. The car was working fine then I
> left it in the
> garage for 2 weeks and now it does not start.
> I know that the cranckshaft is turning properly, no broken
> timing belts
> etc.
>

ThomasE wrote:
> I have not tested for compression but I have no reason to believe that
> anything is wrong with it. The car was working fine then I left it in the
> garage for 2 weeks and now it does not start.
> I know that the cranckshaft is turning properly, no broken timing belts

Yes, it's unlikely you'd lose compression on all four cylinders after
sitting for just two weeks - okay VERY VERY unlikely - but it's worth
checking just to cover all the bases. Low compression combined with
other issues could be the root of your problem.


---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0612-4, 03/25/2006
Tested on: 3/26/2006 11:11:59 AM
avast! - copyright (c) 1988-2005 ALWIL Software.
http://www.avast.com

Fuel pressure is there. After cranking for 20 seconds, no start and fuel
pressure still around 37psi. Also after cranking and turning the key off
the system seems to hold pressure, at least for 5 minutes which perhaps
indicates that injectors are not leaking (am I correct to assume so?)
I also took out all 4 spark plugs and cleaned them but again no firing.
The spark plugs were not completely dry when I took them out but I cannot
evaluate if they were too wet. I assume that after cranking for a while it
would be normal for them to be somewhat wet. I'll repeat taking out the
plugs and inspecting them after cranking.
I'll take out the main relay and resolder it tomorrow. I'm pretty sure the
pump is ok but the relay could still not be feeding voltage to the
injectors properly. Although one would think that that would result in a
code there is no description of the logic that the computer uses to detect
an injector problem condition...

Oh the ignition wires are pretty old and they are OEM. But could all 4
wires fail all of a sudden?

I'll do some more methodical testing tomorrow...

"jim beam" <nospam@example.net> wrote

> no it's not. because it's harder to spark a small gap than a larger one
> at atmosphere, you may not see a spark, even if the system is ok.

Anyone with near 20/20 vision can see the spark on a plug. To bend
the plug only ask for trouble. Each time it bends it has the potential to break.
If you don't see the spark then there is an ignition problem. Better to not
bend it.

> not on a honda and trying to use a normal plug lead it's not. the
> connector is too recessed and the hole too small for the lead to fit.
> if you're /not/ using a plug lead, there's too much chance of leakage to
> spark reliably, particularly if you're trying to spark on a plug without
> the gap opened to work at atmospheric pressure.

Actually, trick requires just a paper clip... no plugs needed.

If you have difficulty checking for a dead plug at the distributor like the
way I do it on Accords, Civic then the timing light is your best friend.
For other's reference: Hook timing light to plug wire, no light = dead plug.
One dead plug = flooding. Flooding = no start.

> besides, if the distributor cap or distributor arm are faulty
> you need to test "downstream" of those components.

You need to test both "downstream" and "upstream."