1988 Honda Accord won't idle when warmed up

On the way to work last week, my Accord died on me when I took it out
of gear (manual trans) as I approached a stop. It restarted but, would
not idle unless I held my foot on the accelerator and kept it at about
1000 rpms. When it's cold, it idles fine but as soon as it warms up
you can watch the rpms drop and it will die. Restart and hold the
accelerator and its fine. I've read that it could be clogged fuel
filter(s) or something to do with the carb. I don't have the money to
take to someone to have it fixed so, I'll have to do it myself and I
don't have the money to replace this and that. BTW it's carburated
not fuel injected. Any help would be appreciated. Thanks

 

check all your vacuum hoses.

 

--------------------

I think it depends on the flow of HOT coolant to set some of the
carburetor's controls. Fill your reservoir to the MAX mark three days in
a row and see if your troubles go away.

'Curly'

 

PCV Valve?
Bg

 

When the engine is cold, it runs at higher rpm until the Fast Idle
Unloader pulls the fast idle cam. From what i understand, in 86-89
accord carbureted, the FIU is controled by a thermo valve. It seems to
be working, changing idle speed as the engine temp changes .

The problem is that now the FIU has pulled the cam, then the idle
speed depends on the throttle stop screw and throttle cable (TC). A TC
hardly needs adjustment but the throttle stop screw is susceptible to
shocks and vibrations if not secured properly. I would suggest an
adjustment of this item. No tools required ( tool-free style screw)

If you can get the desired idle speed after adjusting this, then make
sure that the throttle cable has enough free play (deflection)

If all fail, then you may need to take a look at the idle mixture
screw, but that should be best let to a shop.

 

wrote in

Could be that...

Could also simply be plugged idle jets.

The throttle plate is held slightly open when cold, then is allowed to
close as the engine reaches full op temperature. This means the idle
jets don't control idle until the throttle is fully closed, which is
just about the time the car stalls.

When the OP holds the throttle open, he is shutting down the idle jet
and using other fuel delivery paths, which are not blocked.

If plugged jets are in fact the problem, some compressed air down the
idle speed screw hole should cure that fairly cheaply. Clean the gum and
sediment out of the float bowl as well.

 

I had a similar problem with my '88 carbureted accord. I would be
driving in stop and go traffic and the engine would just cut out on me.
I could always restart it but like your problem, I would have to keep
it revved up a bit to keep it going. I changed the fuel pump, cleaned
and checked everything I could think of.

Finally, I was testing the "primary slow mixture cut-off solenoid valve"
on the back of the carburetor. It's held in with one screw. It has one
wire that energizes the solenoid, and it gets its ground from the
connection to the carburetor. Turned out that over time (17+ years
then, 20 now) the grounding went bad or oxidized to the point of
failure. I simply scratched up the surfaces on the solenoid and
carburetor with sandpaper and no more problem.

I have put this solution out there before, but it can't hurt to post it
again. I hope it helps save a few nice old carbed accords!

dan

 

wrote in @c23g2000hsa.googlegroups.com:

This is not a carb problem, but a 'pre-heated air' delivery problem.
Check and repair the vacuum line to the air diversion damper
in the air intake. The carb needs 100+ deg F air in the Winter.
Pre-heated air from the exhaust manifold prevents frost and ice
build up and might boost your mpg a touch. This happened on my '87
years ago and a five minute fix was all that was needed. Good luck.

 

For the OP, this ground problem could be ruled out by simply using
a lead from a VOM meter. By taking the sharp pointy end of the
lead, and getting a good connection on the slow mixture valve
(at its bracket where the hold down screw is), and connecting the
other end of the lead to the battery negative post, the car would
idle, if the ground was the culprit. A helper would be needed to
hold the engine speed up, to prevent stalling. With a good connection,
the helper lets off the gas pedal, and the engine would then idle.

With a manual trans carb Accord, the normal operation of this valve can be
felt while driving (its subtle). The valve is suppose to close (no fuel
supply to the idle circuit) above 15 MPH/24 [Km/h] (approximately
1700 rpm in second gear). Coast down from 2500 rpm, in second
gear, to about 1200 RPM and you can feel the valve open (fuel supplied
to the idle circuit) at approximately 1700 rpm. The deceleration from
2500 (or above) down to when the valve opens, is very consistent. When
the valve opens (idle circuit now receiving fuel) the deceleration is
less (engine receiving a fuel mixture from the idle circuit and providing
a little power).

A switch on the clutch pedal overrides the fuel cut off (opens the valve)
when shifting gears.

 

Gee, I should have thought of opening the hood in stop and go traffic,
jumping out and jambing a lead from a VOM meter into the "slow mixture
valve", which I was careful to call the "primary slow mixture cut-off
solenoid valve" as in the factory service manual, IN TRAFFIC. It was
INTERMITTENT! Meaning it would happen when the car was warm, and when I
would least expect it to happen. As the OP said, it only happens when
the car is warmed up, or in other words, in TRAFFIC!

It's an intermittent ground. They don't like to do bad things when
you're watching.

I think it is actually a poor design. But that's moot since no Honda
has had a carburetor for at least 15 years? (?).

dan

 

You could simply put the front end up on stands, you know.

M.A. Stewart has some pretty good advice. I'd forgot about that solenoid,
not having much experience with feedback carbs.

Sure it's a poor design. All feedback carbs are poor designs. And your
friendly federal EPA is the felon here, for having mandated bizarre and
unnatural complications into what used to be a very simple device. The EPA
is the reason no American/Canadian car has had a carb since 1989.

 

that's a bad thing. however...

this is a good thing - fuel injection is much more reliable. detroit
would never have made this move without legislation, and we're all much
better off as a result.

 

Detroit attempted fuel injection as early as 1957 (Corvette), making
repeated assaults throughout the decades leading up to the total changeover
to computerized injection around 1989.

The 1976 Cadillac Sedan DeVille had TBI injection. Hemmings magazine
(Oct/07) reports it was "a bit lean at idle" but otherwise worked well.
Huge cost ruled it out for lesser models, and it was phased out later on
due to complications having to do with the then-crude control system.

The 1982 Chrysler Imperial originally had injection, but all of them were
recalled, again due to control problems and retrofitted with a carburetor.
Hemmings recently covered this one as well, but I can't find that issue
just now.

Ford began installing Bosch-derived TBI injection in some models as early
as 1980.

The domestics and the Germans (Bosch L-Jetronic) were far in the vanguard
over the years, well ahead of the Japanese. The Japanese were content to
timidly produce what worked well and did not result in lost sales on
account of poor reliability, accounting for their late entry into the fuel
injection club. Toyota's MR-2 was one of the first port-injected Japanese
cars, appearing in late 1984 with a copy of Bosch's L-Jetronic system.

Honda dutifully followed the other Japanese makers in slowly introducing
injection in the mid-'80s on selected models, but held off where they
could, as long as they could, to keep costs down.

 

again, detroit [or anybody else] would never have made this move [into
the mainstream] without legislation. and the result is better reliability.

sure, plenty of people had messed about with gasoline injection - the
nazi fighter plane, the me109, or variants of it, had fuel injection
back in ww2. but since injection's gone mainstream because of law,
costs have gone down due to volume, and reliability has gone up for
consumers. it's a win for both sides.

 

You originally and specifically said "detroit would never have made this
move without legislation".

I demonstrated that Detroit had been tinkering (and installing) for several
decades before there was any forcible conversion to injection.

The Japanese waited until pretty much the last minute, when they then had
no choice, when emissions regs forced them to convert.

Fuel injection has several important advantages over carburetion, notably
much better driveability and efficiency. I submit that fuel injection would
eventually have become commonplace in North America even in the absence of
regulations. The traditional primary difficulties for fuel injection were
cost and control. Cheap computing power eventually solved both of those,
but by then the regulations were on the march. So we'll never know now...

 

Or... (This is a shot in the dark here), it could be a malfunctioning
idle cutoff valve.

JT

 

Tegger wrote:

Don't get me started.
Don't get me started.
Don't get me started.
Don't get me started.
Don't get me started.

JT

(Who would love to find real EN1 and EM1 engines...)

 

Poppycock!

In the olde dayz, when things were simple, carbed cars were easy to work
on and a helluva lot less 'xpensive to work on.

That's exactly why my cutoff date for Honda ownership is 1983. After
that milestone, things REALLY got complicated.

JT

 

poppycock yourself. as a guy that can strip, clean, repair and
calibrate pretty much any carb you care to put in front of me, i'll take
electronic injection any day. for regular form and function, carbs just
can't compete.

the only exception i'd give you in that is racing - a pair of dcoe40
weber's at full throttle are quite excellent.

 

On Jan 27, 12:47 pm, Grumpy AuContraire <>
wrote:
snip

I can vouch for that. I used to have a photo of a buddy and me
standing on the fender of a pickup, pissing onto a frozen carburetor
to de-ice it. After several such applications (good thing our group of
five had several thermos' filled with coffee) we were successful and
were able to drive back into Prudhoe Bay.

While lots of early fuel injectors were not especially reliable the
new ones are. I gotta agree with the folks who propose that current
fuel injection systems are very reliable (especially if you stick to
Top Tier gasolines).

JT is right that when a fuel injection system goes TU the fix can
often be expensive and difficult to diagnose. Of course, the same
could be said for any number of systems built into today's cars.