Honda Car Forum

my son has a 90 civic that will not start when it is hot outside or when
the engine is hot. once it starts it runs fine. some people say fuel pump,
but i think that it wouldn't run right after it started if that was the
problem. I saw another post about a main relay being a problem but i'm not
familiar with that, either what it does, where it is located, or what to do
about it.
is this a coomon problem with that breed of civics and can anyone tell me
where to start looking to fix this problem

I forgot to mention that it cranks just fine, it just won't turn over.
Almost like it is out of gas, but that is not the problem. sometimes
starting fluid gets it running. sometimes it does not. any ideas?

"jerry250d" <gcs566@aol.com> wrote in message
news:ffe67e16275179d9a3dc58ae01a6973b@localhost.ta lkaboutautos.com...
> my son has a 90 civic that will not start when it is hot outside or when
> the engine is hot. once it starts it runs fine. some people say fuel pump,
> but i think that it wouldn't run right after it started if that was the
> problem. I saw another post about a main relay being a problem but i'm not
> familiar with that, either what it does, where it is located, or what to
> do
> about it.
> is this a coomon problem with that breed of civics and can anyone tell me
> where to start looking to fix this problem

Extremely common
http://www.tegger.com/hondafaq/start...html#mainrelay

jerry250d wrote:
>
> I forgot to mention that it cranks just fine, it just won't turn over.
> Almost like it is out of gas, but that is not the problem. sometimes
> starting fluid gets it running. sometimes it does not. any ideas?

It's most likely the main relay. It controls current flow to the fuel pump
and the fuel injectors. It can be found under the dash on the far left side
just above and to the left of the coin tray. It's a common problem. You
can read more about on Tegger's FAQ,
http://www.tegger.com/hondafaq/start...html#mainrelay. In addition to
the problems with the cracked solder joints that Tegger describes, the
relays inside the unit tend to get pitted like an old set of points. If
you're good with electronics, you can try resoldering it (but that won't
help if you have the pitting problem). Or, you can just get a new one from
the Honda dealer. I think they run around $40 or so.

Eric

I just had the main relay replaced on my 93 Accord. Are the new relays
subject to the same failure as the one they are replacing or has Mitsuba
fixed their manufacturing process?
Thanks,
Rich
Eric wrote:
> jerry250d wrote:
>
>>I forgot to mention that it cranks just fine, it just won't turn over.
>>Almost like it is out of gas, but that is not the problem. sometimes
>>starting fluid gets it running. sometimes it does not. any ideas?
>
>
> It's most likely the main relay. It controls current flow to the fuel pump
> and the fuel injectors. It can be found under the dash on the far left side
> just above and to the left of the coin tray. It's a common problem. You
> can read more about on Tegger's FAQ,
> http://www.tegger.com/hondafaq/start...html#mainrelay. In addition to
> the problems with the cracked solder joints that Tegger describes, the
> relays inside the unit tend to get pitted like an old set of points. If
> you're good with electronics, you can try resoldering it (but that won't
> help if you have the pitting problem). Or, you can just get a new one from
> the Honda dealer. I think they run around $40 or so.
>
> Eric

"MAT" <marcoat*RM_@SPAM_*hotmail.com> wrote in
news:__Wdne35UbpDXVDfRVn-tg@comcast.com:

>
> "jerry250d" <gcs566@aol.com> wrote in message
> news:ffe67e16275179d9a3dc58ae01a6973b@localhost.ta lkaboutautos.com...
>> my son has a 90 civic that will not start when it is hot outside or
>> when the engine is hot. once it starts it runs fine. some people say
>> fuel pump, but i think that it wouldn't run right after it started if
>> that was the problem. I saw another post about a main relay being a
>> problem but i'm not familiar with that, either what it does, where it
>> is located, or what to do
>> about it.
>> is this a coomon problem with that breed of civics and can anyone
>> tell me where to start looking to fix this problem
>
> Extremely common
> http://www.tegger.com/hondafaq/start...html#mainrelay
>



Took the words right out of my mouth!


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

jerry250d wrote:
> my son has a 90 civic that will not start when it is hot outside or when
> the engine is hot. once it starts it runs fine. some people say fuel pump,
> but i think that it wouldn't run right after it started if that was the
> problem. I saw another post about a main relay being a problem but i'm not
> familiar with that, either what it does, where it is located, or what to do
> about it.
> is this a coomon problem with that breed of civics and can anyone tell me
> where to start looking to fix this problem
>

Let me guess: The starter turns the engine properly, but it seems like
it's not getting any fuel. And if you keep the key turned long enough,
the Check Engine light will come on. Am I right? If so, the problem
is definitely the main relay, which these other guys have been pointing
you to. (I added this because I own a 1990 Civic myself and am very
familiar with this problem) If you own and are handy with a soldering
iron, you can fix this problem yourself for free. See Tegger's FAQ.
Also, read through the thread I posted, subject is "90 Civic Main Relay
and More"

Good Luck!

Jonathan

P.S. You can bet on having to replace/fix the main relay every 2 years
or so if you don't buy a brand-new one. I've had my Civic since 2001
and I've just now fixed the main relay problem for the 3rd time.
However, I admit the first two times I just bought another used one
cheap from a junkyard. ;-)

"Rich" <rgsrx@cox.net> wrote in message
news:VYkze.7331$HV1.1494@fed1read07...
>I just had the main relay replaced on my 93 Accord. Are the new relays
>subject to the same failure as the one they are replacing or has Mitsuba
>fixed their manufacturing process?
> Thanks,
> Rich

I'd bet the vulnerability is still there. The basic problem is they mount
heavy items (the relays themselves) on circuit boards using the solder for
the mechanical support, then mount the whole thing to the car chassis so the
road and engine vibration can fatigue the solder. A lot of mfrs do it
because the problem rarely shows up within the warranty period.

Mike

Jonathan Upright <qaesar1@carolina.rr.com> wrote in
news:Xruze.7401$%y1.112945@twister.southeast.rr.co m:

> jerry250d wrote:
>> my son has a 90 civic that will not start when it is hot outside or
>> when the engine is hot. once it starts it runs fine. some people say
>> fuel pump, but i think that it wouldn't run right after it started if
>> that was the problem. I saw another post about a main relay being a
>> problem but i'm not familiar with that, either what it does, where it
>> is located, or what to do about it.
>> is this a coomon problem with that breed of civics and can anyone
>> tell me where to start looking to fix this problem
>>
>
> Let me guess: The starter turns the engine properly, but it seems
> like it's not getting any fuel. And if you keep the key turned long
> enough, the Check Engine light will come on. Am I right? If so, the
> problem is definitely the main relay, which these other guys have been
> pointing you to. (I added this because I own a 1990 Civic myself and
> am very familiar with this problem) If you own and are handy with a
> soldering iron, you can fix this problem yourself for free. See
> Tegger's FAQ. Also, read through the thread I posted, subject is "90
> Civic Main Relay and More"
>
> Good Luck!
>
> Jonathan
>
> P.S. You can bet on having to replace/fix the main relay every 2
> years or so if you don't buy a brand-new one. I've had my Civic since
> 2001 and I've just now fixed the main relay problem for the 3rd time.
> However, I admit the first two times I just bought another used one
> cheap from a junkyard. ;-)
>

I resoldered my 94 Integra MR only once in 4 years.Not a single problem
since.
And I live in Florida,a sunny,hot climate.

--
Jim Yanik
jyanik
at
kua.net

Michael Pardee wrote:
>
> I'd bet the vulnerability is still there. The basic problem is they mount
> heavy items (the relays themselves) on circuit boards using the solder for
> the mechanical support, then mount the whole thing to the car chassis so
> the road and engine vibration can fatigue the solder. A lot of mfrs do it
> because the problem rarely shows up within the warranty period.
>
> Mike

Hmmm, wouldn't a potential solution be to soft mount it to the chassis with
some rubber bushings?

Eric