Bad start in hot weather?

Maybe a weak fuel pump. Pause the key in the "ON" position for one
second before cranking. It gives the pump some time to run at full
voltage.

 

Well, I'm thinking of giving up searching the problem of bad start in
hot weather but I'll give it a last try to find out what could it be so I
ask anyone who has an oppinion of what it could be and why?

Thanx.
In advance, please ignore mistakes in writing.


Car: Honda Civic Coupe 1.5iLS 1995. year, 101 HP, fuel injected

Problem: Car starts purely when it has been sitting in the hot sunny weather
for about 2 hours, and it also starts purely when sitting
on a hot sunny
weather and was previously not driven.
By starting purely I mean cranking for for four or five
cranks and then
starting irregularely, and it takes about 2-3 seconds to
turn the oil lamp
off, in that time RPM also rise to about propper value.
Next start immediately after engine was turned off or a
time of up to half
an hour or hour it starts ok (two cranks and ignite).
When started in the morning whan it is not hot, it starts
immediately on the
first crank.

Other observations: When fuel reservoir cap is taken off after beeing driven
there is
woosh sound of air comming out (I'm not 100% sure maybe the
air is getting in
the reservoir).
When I left it parked in the sun but I left the engine part
in shade it started ok
(that would exclude cabbin temperature and temperature
around reservoir
to have anything to do with the problem - but lets take
that in conssideration).

Checked or replaced parts: - resoldered main relay
- ignition coil resistance OK
- Ignition Control Module (ICM) resistance OK
- Engine Coolant Temperature (ECT) sensor resistance OK
- new spark plugs
- new fuel filter
- cleaned air filter (K&N)
- EVAPorative emmision control solenoid valve (EVAP)
working OK
- Intake Air Temperature (IAT) sensor resistance OK
- Idle Air Control (IAC) valve OK (checked by disconnecting
in idle -> RPM fall)
- injectors not leaking (checked under pressure out of the
car)
- ECM displays no error codes

Well, what else could it be?

 

Enough checks and repairs. It's time to *replace*.

I would start in order with each of the following until the problem clears:

Replace the main fuel relay. I think it's the number one cause of Civic's
not starting after driving a bit in hot weather.

Replace the spark plug wires with new, OEM wires.

Replace the ignition coil. Checks don't always indicate that it's
malfunctioning.

Replace the ignition control module (a.k.a. the ignitor). But I doubt it's
this, as the car probably wouldn't start, period.

 

I'll try this.

I might try this, but I dubt it could be the problem.

It is a bit difficult (expensive) to find this part but I'll trie to find
it.

I will not try this.

Thanx.

 

If expensive, I hear you. Around $100 at the dealer's. But online companies
sell them, often for less. For example, an OEM coil for what may (maybe not)
be your car goes for around $40 at:

http://catalog.honda-auto-parts-wholesale.com/?make=HO&year=1991&imageField.
x=53&imageField.y=16

It's $71 at

http://www.hondaautomotiveparts.com/auto/jsp/mws/prddisplay.jsp?inputstate=5
&catcgry1=Civic&catcgry2=1995&catcgry3=3DR+SI&catcgry4=KA5MT&catcgry5=DISTRI
BUTOR+%28TEC%29

(But again, I may not have nailed your car exactly when doing the quick
search.)

Dealers should have them, too.

Tom and Ray, as well as some here, talk about the coil often being the
culprit when the car is having problems at high temperatures. My own coil
checked out fine a few months ago (after dying repeatedly *while driving*
and after well- warmed up) but then was found to be the problem a few days
later, after another tow. But it wasn't really a starting problem.

 

Thanks, on your comments.

 

I had the same problem in my 91 Accord SE 2 weeks ago.
The dealer said that the main relay was shorting out when hot.
No problems since it was replaced.

Symptoms: Would not start after sitting in hot sun.
Would not start after having been driven for a while and then stopped
-- unless you let it sit for 20 min.

The dealer told me it was located under the left front dash
and that's why opening the driver's door to cool off the relay would solve
the problem.

The dealers up here in Ottawa seem to know about these problems
and can fix them.

LRM

 

Same problem with my '88 Civic and my parents' '89.
You would thing that considering the number of cars potentially
affected by the main relay problem (Civics/Accords, etc.) that
every dealer would spot it right away instead of blindly thowing
parts at a problem. Oh, the dealer only sell and service the cars,
they don't "represent" the manufacturer... Anyway, I've even
approached a cranking Civic in a parking lot and offered my
assistance.

Opening the door never fixed it for me, although I drove
an entire winter and it work perfectly until spring came along.

 

As already mentioned, this suggests some leakiness of injector(s)... even a
very slight leak. IOW the manifold is loaded with gasoline vapor and
opening the throttle plate clears it out quickly. Have you tried a bottle
of FI cleaner to see if it helps?

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??