1991 Honda Civic dies after driving on freeway

My girlfriend's '91 Civic has 150k+ miles on it and just started acting
up. The car runs fine while driving around town, but once we get it up
to high speeds it will just all of a sudden die the next time we slow
down. Most of the time it starts right back up within a minute or so,
but the last time it took about 20 minutes to start up again.

We took it to our regular mechanic, who took it out for a test drive
and never experienced a problem. He said it might be the fuel pump, but
that he wasn't sure.

After reading through newsgroups on the subject, it seems that maybe
the problem is the main relay switch. Any suggestions?

 

My girlfriend's '91 Civic has 150k+ miles on it and just started acting
up. The car runs fine while driving around town, but once we get it up
to high speeds it will just all of a sudden die the next time we slow
down. Most of the time it starts right back up within a minute or so,
but the last time it took about 20 minutes to start up again.

We took it to our regular mechanic, who took it out for a test drive
and never experienced a problem. He said it might be the fuel pump, but
that he wasn't sure.

After reading through newsgroups on the subject, it seems that maybe
the problem is the main relay switch. Any suggestions?

The main relay would be my guess. I suggest that you visit the
http://www.tegger.com website and do some research on the main relay.

 

My idea is that the coil is weak and the freeway driving is keeping it
cool enough to work until there's more heat from local driving after
the freeway driving.

 

My money's on the coil, too. Especially if the problem only
occurs well after warm-up.

A failing main relay's symptoms tend to occur after running
awhile, then shutting off a few minutes, then re-starting.
It won't re-start until the car cools. The integrity of the
solder joints, with age, are temperature-dependent.

How old is the coil? Is the coil OEM?

Still, ever had the main relay replaced?

I replaced my 91 Civic's (176k miles) main relay c. 1999. No
problems since.

 

wrote in

Here's a tip: Next time it dies and won't start, watch the tach needle as
you crank. Does it jump up a tiny bit? If so, the coil is bad. If NOT, the
igniter has bit the dust. (If you have no tach, it's a bit harder to tell
the difference between coil and igniter.)

Once you've tested it as above, check for spark as shown here:
http://www.tegger.com/hondafaq/startproblems.html#checkspark
just to make sure there is, in fact, no spark.

You've got a 50-50 chance of it being a the coil or igniter. I'm going to
go with the coil for now. If you have some time, you can tell more by
testing as per this:
http://www.tegger.com/hondafaq/startproblems.html#badigniter

 

that's not a bad call, but it could also be the condenser. they tend to
break down over the years, and spark gets progressively weaker as it
does. heat only makes it worse.

 

Okay, I'm going to check this out first thing tomorrow. I'll post my
results. Thank you so much for the wonderful advice. Ya'll are the
best!

 

For a variety of reasons, I couldn't test the car until today. It has
not been driven at all since then (two weeks), but when I got ready to
test it today, here's what I got:

1. The car fired right up.
2. I let the engine warm up for about 5 minutes.
3. Then I drove around the block four or five times.
4. Then I took it up to 50mph for a couple of minutes.
5. When I dropped the speed to under 5mph, the car died.
6. After waiting less than 15 seconds, I started the car again with no
problem.
7. I repeated steps 2-4 again and again, but the car never died on me
again.

The only thing I did notice was that at one point, when the car was
idling, a little bit of burnt-oil smelling smoke came out of the vent.
There was no smoke when I opened up the hood, but there was kind of a
lingering burnt-oil smell. I don't know if that is in any way related
to my problems, but I just can't figure out why the car would only
intermittently stop working.

 

wrote in

Next time you test the car, take a passenger with you. When the car stalls
next, immediately jump out and check for spark while the other person
cranks the starter.