Honda Car Forum

My 1993 Civic has new-onset failure to start. The problem has occurred
sporadically and only on very hot days. A friend swears it's vapor
lock; previous posts to this group indicate that vapor lock is very
unlikely and suggests a main relay problem.

* *{Additonal data:
Several times the problem was solved by waiting til the next morning
and trying again.
Two other times we've put STP Gas Treatment in the tank and the car
started up immediately.
The problem never occurred until this year. The first time the car
wouldn't start, the positive battery terminal was severely corroded.
Cleaning it did not start the car. The car started right up when the
mechanic checked it hours later. He noted that, unrelated, the head
gasket needed to be replaced, and he did that.}


My questions: if it were a main relay, why would the problem only occur
on scorching hot days? In any case, why would such a problem have
sudden onset? (I'm the original owner and this has never happened
before this year.) Could it have anything to do with ethanol
supplemented gasoline? Thanks

"havses@hotmail.com" <georgehav@gmail.com> wrote
> My 1993 Civic has new-onset failure to start. The problem
> has occurred
> sporadically and only on very hot days. A friend swears
> it's vapor
> lock; previous posts to this group indicate that vapor
> lock is very
> unlikely and suggests a main relay problem.
>
> * *{Additonal data:
> Several times the problem was solved by waiting til the
> next morning
> and trying again.
> Two other times we've put STP Gas Treatment in the tank
> and the car
> started up immediately.
> The problem never occurred until this year. The first time
> the car
> wouldn't start, the positive battery terminal was
> severely corroded.
> Cleaning it did not start the car. The car started right
> up when the
> mechanic checked it hours later. He noted that, unrelated,
> the head
> gasket needed to be replaced, and he did that.}
>
>
> My questions: if it were a main relay, why would the
> problem only occur
> on scorching hot days?

The high heat expands the solder joints inside the main
relay. The joints fail, meaning they won't conduct
electricity.


> In any case, why would such a problem have
> sudden onset? (I'm the original owner and this has never
> happened
> before this year.) Could it have anything to do with
> ethanol
> supplemented gasoline?

No. The main relay problem is strictly an electrical
problem, insofar as car systems are concerned.

http://www.tegger.com/hondafaq/start...html#mainrelay
has a discussion on the main relay. Note the suggestion
(among others) to smack the dash to help identify whether
the main relay is the problem.

If it's never been replaced or repaired before, it's a very
strong candidate for your problem.

Many mechanics do not know about it. Honda owners do.

"Elle" <honda.lioness@nospam.earthlink.net> wrote in
news:nynBg.5207$0e5.2369@newsread4.news.pas.earthl ink.net:


>
> If it's [the Main Relay] never been replaced or repaired before, it's
> a very strong candidate for your problem.
>
> Many mechanics do not know about it. Honda owners do.
>
>
>



Very odd, that, isn't it?

Something less than half the email I get has to do with the single problem
of the Main Relay. It is easily the #1 Honda problem, far outstripping any
other single issue. And yet almost none of the pros are even vaguely aware
of it.

--
TeGGeR®

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

"havses@hotmail.com" <georgehav@gmail.com> wrote in
news:1154875904.337362.139480@p79g2000cwp.googlegr oups.com:

> My 1993 Civic has new-onset failure to start. The problem has occurred
> sporadically and only on very hot days.



See Elle's response. It's your PGM-FI Main Relay.

--
TeGGeR®

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

TeGGeR® wrote:
> "Elle" <honda.lioness@nospam.earthlink.net> wrote in
> news:nynBg.5207$0e5.2369@newsread4.news.pas.earthl ink.net:
>
>
>> If it's [the Main Relay] never been replaced or repaired before, it's
>> a very strong candidate for your problem.
>>
>> Many mechanics do not know about it. Honda owners do.
>>
>>
>>
>
>
>
> Very odd, that, isn't it?
>
> Something less than half the email I get has to do with the single problem
> of the Main Relay. It is easily the #1 Honda problem, far outstripping any
> other single issue. And yet almost none of the pros are even vaguely aware
> of it.
>
actually, if you're used honda scuzzbag like me, this is a great thing.
it means you can buy non-functioning hondas for almost nothing and
drive around in a virtually free car. or give them to friends. feel
the love, man!

"TeGGeR®" <tegger@tegger.c0m> wrote
> "Elle" <honda.lioness@nospam.earthlink.net> wrote
>> If it's [the Main Relay] never been replaced or repaired
>> before, it's
>> a very strong candidate for your problem.
>>
>> Many mechanics do not know about it. Honda owners do.
>>
>>
>>
>
>
>
> Very odd, that, isn't it?

Yes. I think it's quite an argument for the value of
amateurs posting their experiences to internet fora like
this. The database is enormous and often is scientifically
significant.

> Something less than half the email I get has to do with
> the single problem > of the Main Relay. It is easily the
> #1 Honda problem, far outstripping any > other single
> issue.

This data point in itself is important.

Aside: I was just reading your PCV site. I have long
wondered how your 91 Integra's PCV valve stayed pristinely
clean for over 200k miles while my 91 Civic's was "chock
full of waxy buildup" at about 140k miles. This is despite
my frequent (every 6 mos/3k miles for many years, followed
by 6 mos/5k miles more recently) oil changes since buying
the car new in 1991.

Last winter I found my PCV valve had way more waxy specks
than usual following the use of STP fuel system cleaner. I
hardly ever get the specks with Chevron Techron fuel system
cleaner. You say you have used only Chevron gas, known to
have cleaners in it. I have always used whatever gas was
cheapest. I wonder if this explains the difference between
your and my differing PCV valve experiences.

Just thought I'd toss that in there for the weekend car talk
series.

jim beam <nospam@example.net> wrote in
news:bc2dnUAhAvX07kvZnZ2dnUVZ_o2dnZ2d@speakeasy.ne t:

> TeGGeR® wrote:
>> "Elle" <honda.lioness@nospam.earthlink.net> wrote in
>> news:nynBg.5207$0e5.2369@newsread4.news.pas.earthl ink.net:
>>
>>
>>> If it's [the Main Relay] never been replaced or repaired before,
>>> it's a very strong candidate for your problem.
>>>
>>> Many mechanics do not know about it. Honda owners do.
>>>
>>>
>>>
>>
>>
>>
>> Very odd, that, isn't it?
>>
>> Something less than half the email I get has to do with the single
>> problem of the Main Relay. It is easily the #1 Honda problem, far
>> outstripping any other single issue. And yet almost none of the pros
>> are even vaguely aware of it.
>>
> actually, if you're used honda scuzzbag like me, this is a great
> thing.
> it means you can buy non-functioning hondas for almost nothing and
> drive around in a virtually free car. or give them to friends. feel
> the love, man!
>


LOL

--
TeGGeR®

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

"Elle" <honda.lioness@nospam.earthlink.net> wrote in
news:j%vBg.4923$xp2.4166@newsread1.news.pas.earthl ink.net:


> You say you have used only Chevron gas,


I'm kind of curious where you found that. Chevron does not have retail
outlets in Canada. Nor does it sell its Techron additive in stores up here
(tho' I wish it did...).


> known to
> have cleaners in it. I have always used whatever gas was
> cheapest.



I've used Imperial Oil (Exxon) almost 100% over the last 15.5 years. In
Ontario, Canada, that means the old eastern-US "ESSO" brand, by which name
the retail stores are still known up here. I use ESSO because they are the
last major up here to not use ethanol.

(As an aside, ESSO originally stood for "Eastern Seaboard Standard Oil".
Nobody knows that these days...)



> I wonder if this explains the difference between
> your and my differing PCV valve experiences.



Your situation is most intriguing. I wish I could see your car personally.
I've seen sludgy buildup many times, but never the waxy stuff you describe.



--
TeGGeR®

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

TeGGeR® wrote:

> I've used Imperial Oil (Exxon) almost 100% over the last 15.5 years. In
> Ontario, Canada, that means the old eastern-US "ESSO" brand, by which name
> the retail stores are still known up here. I use ESSO because they are the
> last major up here to not use ethanol.

I had been filling up at Sunoco for the last 3 years, and only recently I
noticed on one pump that their gas had some amount of ethanol in it (I
forget the actual percentage, but I think it was 10%). Not to defend the
use of ethanol, but so far my '93 Accord's performance and gas mileage have
not suffered as a result of using Sunoco gas (I still average 33mpg on the
highway, which is well above EPA's original estimate). Perhaps I should try
Esso again to see if slight improvements in both can still be achieved.

TeGGeR® wrote:
> the retail stores are still known up here. I use ESSO because they are the
> last major up here to not use ethanol.
>
> (As an aside, ESSO originally stood for "Eastern Seaboard Standard Oil".
> Nobody knows that these days...)

Interesting about the Esso brand because I have a nice lighted oval
shaped Esso sign hanging in my basement that was trashed when they were
swapping all the Esso signs around here to Exxon. I figured it was a bit
of a treasure by now because they had been gone so long. Well, it still
makes a nice light! :-)