Intermittent engine stalling, v 2

I have been having intermittent stalling of the engine for a long time now.
At fairly random times the engine completely cuts out for a brief moment
after which it picks up again normally. This is typically immediately
followed by one or two similar stumbles, and then problemless driving.

It happens at fairly random times, though it is much more likely to occur
just after I have started driving, and it seems to have some correlation with
significant road roughness. On the other hand, I might have been driving for
many hours, and then suddenly on a beautifully smooth asphalt road, it cuts
out, out of the blue sky, so to speak.

Water in the fuel seemed to be a plausible cause, but I put several
bottles of Heet and similar through, and it stayed. In addition, after
half a year or so, a fuel tank removal and cleaning, and about 5,000
miles, it is hard to see how the water could still stick around. So
I am now thinking ignition.

Yesterday afternoon, while driving normally on a two lane highway, for the
first time the engine did not want to recover, and it did not want to restart
on the side of the road. I probably flooded it; clouds of blue smoke came out
of the tail pipe cranking it, despite the fact that there was no sign of
ignition. Also, I noticed a strong smell of fuel, so fuel was obviously being
delivered.

Anyway, after an hour wait and some cranking with the fuel fuse out, it still
did not want to start, and I had it towed to a shop. Needless to say, when
the shop tried next morning it started and ran fine, after the flooded fuel
was gone, so the problem could not be determined.

So it seems that the problem is the ignition cutting out, rather than the
fuel delivery. Unfortunately, the thing is irreproducible for examination,
so as far as I see, the only thing to do is to start replacing parts
until it goes away. (Correction, but I already know the other thing to do
is write down the telephone numbers of the local towers; the AAA took two
hours to arrive, after the thunderstorm had come and gone.)

The question is: any suggestions on which parts to replace first? What
parts are likely to develop problems on a 134k Miata that has seen some
very rough treatment?

Leon

--
Leon van Dommelen Bozo, the White 96 Sebring Miata .)
http://www.dommelen.net/miata
EXIT THE INTERSTATES (Jamie Jensen)

I would first do the fuel filler if thats not it I will look at the coils
sometimes there could be a crack in a coil and when it heats up the crack
gets bigger and then shorts out and that whats making it bog out and then
sometimes pick up or heats up so much cuts out then when it cools down
it will go again Happen to me on another car I had
let us know in the group here

"Leon van Dommelen" > wrote in message
news
>
> I have been having intermittent stalling of the engine for a long time
> now.
> At fairly random times the engine completely cuts out for a brief moment
> after which it picks up again normally. This is typically immediately
> followed by one or two similar stumbles, and then problemless driving.
>
> It happens at fairly random times, though it is much more likely to occur
> just after I have started driving, and it seems to have some correlation
> with
> significant road roughness. On the other hand, I might have been driving
> for
> many hours, and then suddenly on a beautifully smooth asphalt road, it
> cuts
> out, out of the blue sky, so to speak.
>
> Water in the fuel seemed to be a plausible cause, but I put several
> bottles of Heet and similar through, and it stayed. In addition, after
> half a year or so, a fuel tank removal and cleaning, and about 5,000
> miles, it is hard to see how the water could still stick around. So
> I am now thinking ignition.
>
> Yesterday afternoon, while driving normally on a two lane highway, for the
> first time the engine did not want to recover, and it did not want to
> restart
> on the side of the road. I probably flooded it; clouds of blue smoke came
> out
> of the tail pipe cranking it, despite the fact that there was no sign of
> ignition. Also, I noticed a strong smell of fuel, so fuel was obviously
> being
> delivered.
>
> Anyway, after an hour wait and some cranking with the fuel fuse out, it
> still
> did not want to start, and I had it towed to a shop. Needless to say,
> when
> the shop tried next morning it started and ran fine, after the flooded
> fuel
> was gone, so the problem could not be determined.
>
> So it seems that the problem is the ignition cutting out, rather than the
> fuel delivery. Unfortunately, the thing is irreproducible for
> examination,
> so as far as I see, the only thing to do is to start replacing parts
> until it goes away. (Correction, but I already know the other thing to do
> is write down the telephone numbers of the local towers; the AAA took two
> hours to arrive, after the thunderstorm had come and gone.)
>
> The question is: any suggestions on which parts to replace first? What
> parts are likely to develop problems on a 134k Miata that has seen some
> very rough treatment?
>
> Leon
>
> --
> Leon van Dommelen Bozo, the White 96 Sebring Miata .)
> http://www.dommelen.net/miata
> EXIT THE INTERSTATES (Jamie Jensen)

Leon,
Too much White Paint for the Florida sun. :-)

Bruce RED '91

(BRUCE HASKIN) wrote:


>Too much White Paint for the Florida sun. :-)

Certainly the additional speed has lead to additional wear
and tear. Maybe I should have bought a red one anyway.

Nah.
Leon

--
Leon van Dommelen Bozo, the White 96 Sebring Miata .)
http://www.dommelen.net/miata
EXIT THE INTERSTATES (Jamie Jensen)

In article <o1cLe.200961$s54.130159@pd7tw2no>,
"Dale" > wrote:

> I would first do the fuel filler if thats not it I will look at the coils
> sometimes there could be a crack in a coil and when it heats up the crack
> gets bigger and then shorts out and that whats making it bog out and then
> sometimes pick up or heats up so much cuts out then when it cools down

I agree with the coil packs being prime suspects, except both would have
to fail simultaneously for the engine to quit.

Leon, have you cleaned the ground points recently? Jumpiness in the tach
needle is a sign of poor ignition grounding. The major grounds are on
the head near the former location of the throttle body, and the
multiconnector under the master cylinders.

---
Lanny Chambers
'94C, St. Louis
http://www.hummingbirds.net/alignment.html

Leon, you know that if you had a red one, it would have been much slower
and the problems that you are having would just come later on. With the
WHITE, you just got to the problems before we will.

(With the white cars, they are ahead of us in time) :-)

Bruce RED '91

Lanny Chambers > wrote:

>In article <o1cLe.200961$s54.130159@pd7tw2no>,
> "Dale" > wrote:
>
>> I would first do the fuel filler if thats not it I will look at the coils
>> sometimes there could be a crack in a coil and when it heats up the crack
>> gets bigger and then shorts out and that whats making it bog out and then
>> sometimes pick up or heats up so much cuts out then when it cools down
>
>I agree with the coil packs being prime suspects, except both would have
>to fail simultaneously for the engine to quit.

Yes. Most definitely the engine always stops completely. It does not
run rough on two cylinders.

I am now thinking about the ignition switch. Should have thought of that
one right away. I think I will take my starter button out of the circuit
first too. I had problems with the big red button, so why not with the
KGW?

>Leon, have you cleaned the ground points recently? Jumpiness in the tach
>needle is a sign of poor ignition grounding.

I can do it again. But the tach is not jumpy, and a LINK log I once took
did not show anything in the sensors during the stalling that I could find.

> The major grounds are on
>the head near the former location of the throttle body, and the
>multiconnector under the master cylinders.

I know about the ground below the master cylinder (especially that
I have to remove the SC to get at it.) I will look for the one on the
head.

Thanks,
Leon

--
Leon van Dommelen Bozo, the White 96 Sebring Miata .)
http://www.dommelen.net/miata
EXIT THE INTERSTATES (Jamie Jensen)

In article >,
(Leon van Dommelen) wrote:

> I am now thinking about the ignition switch.

Ah, you may be onto something there. I always forget about the switch.

> I know about the ground below the master cylinder (especially that
> I have to remove the SC to get at it.) I will look for the one on the
> head.

Sometimes the nut that secures the ground terminal gets loose.
Retightening it may not be enough, since loose connections invite
corrosion. As you know, I'm sure.

---
Lanny Chambers
'94C, St. Louis
http://www.hummingbirds.net/alignment.html

I'm having the same problem with an '87 Mazda pick-up only with a slight
variation. Nearly every time I come to a stop, the engine quits as if I'd
turned off the ignition,regardless if the engine is hot or cold. It
easily starts again and to get moving, I need to give it a little more gas
while I shift into drive. (auto trans) Have replaced a cracked distributor
cap and flushed the fuel line, and a 180 bucks later am no further ahead.
Any suggestions?

Lanny Chambers > wrote:

>In article <o1cLe.200961$s54.130159@pd7tw2no>,
> "Dale" > wrote:
>
>> I would first do the fuel filler if thats not it I will look at the coils
>> sometimes there could be a crack in a coil and when it heats up the crack
>> gets bigger and then shorts out and that whats making it bog out and then
>> sometimes pick up or heats up so much cuts out then when it cools down
>
>I agree with the coil packs being prime suspects, except both would have
>to fail simultaneously for the engine to quit.
>
>Leon, have you cleaned the ground points recently? Jumpiness in the tach
>needle is a sign of poor ignition grounding. The major grounds are on
>the head near the former location of the throttle body,

There is a ground strap there? Or just grounded wires?

Leon

> and the
>multiconnector under the master cylinders.
>
>---
>Lanny Chambers
>'94C, St. Louis
>http://www.hummingbirds.net/alignment.html

--
Leon van Dommelen Bozo, the White 96 Sebring Miata .)
http://www.dommelen.net/miata
EXIT THE INTERSTATES (Jamie Jensen)