Volvo stumbled and died a couple times - spark or fuel?

[CJFusco]

On the drive home today, the Volvo stumbled and died a couple times. I noticed that the idle felt a little weird at a stoplight, almost as if one cylinder was missing. Then it stumbled and died. I started her back up - it took more cranks than usual, but it started.

It ran fine for a few more minutes, then stumbled and died again coming around a corner. It started up again, but again took more cranks than usual. Once again, at the next stop light, the idle felt erratic, as if a cylinder were occasionally missing... it felt like one drop of revs every few seconds, as if the cylinder were firing correctly most of the time.

The only other time I recall the car having this kind of idle -maybe about a week ago- it was raining out. It is also raining today. A connection there?

Do we think this is a spark problem, a fuel problem, or other? My first instinct says "replace spark plugs," but anything else I might want to try first?

[NICKG]

spray starter fluid in the engine thru a vacuum port...if it is a fuel issue it will start right up...if not it is spark related. this is the first thing anyone should do to diagnose a no start or died condition

[CJFusco]

Thanks for the reply, but the problem is that I have no way to get to the auto parts store right now to get starter fluid... because the car now will not start. It just turns and turns and turns.

Battery seems fine. No missing coolant, so it isn't a head gasket. No weird sounds or smells or smoke.

I am thinking either plugs, distributor, coil, or fuel filter...

Car is a 1990 Volvo 740 GLE with the 2.3 liter 16-valve 4 cyl, by the way.

[CJFusco]

I let the car sit in my garage for a bit and it started right up and idled fine. The car is almost out of gas - I think I might run out to fill up the tank and hit the auto parts store, getting some plugs and some starter fluid just in case.

[the]

Not sure where the injection computer brain is located on that car, but make sure that it isn't getting wet during the rain. If the brain is located in the glovebox or dash somewhere, rain leaking in through the windshield seal can sometimes get into it (happened on my BMW). On my car, the moisture was affecting the signal from one of the coolant temp sensors.

[CJFusco]

Good idea, the. I'll look into it.

[charlesbahn]

This car has a fuel pump relay which is notorious for going bad and causing this problem. It is located behind the ashtray and is inexpensive and easy to fix. Might be something else, but replacing this fixed mine.

[Instrument 41]

Sounds like a secondary ignition problem. The comment about the relay is correct. If you handy, a lot of time the problem with the relay is broken soldier joints, and these can be re-soldier. A cap, rotor, plugs and wires for this car at Auto Zone will run about $70 for all of it.

[CJFusco]

By "this car" do you mean the Volvo 740?

I know that they changed a lot of details for this line of car in 1990, so some of the aspects of the 1980s designs might not apply to my car... but I will look into it. Thanks.

I just realized how much the plot of this thread is reminiscent of something that Hemingway would write, if he were a car enthusiast:

"The Volvo stumbled, then died. In the rain."

[charlesbahn]

Yes 1991 740. It's a common problem.

[CJFusco]

I checked the relays; well, actually, I couldn't get the relay panel out of the center console, but a couple of the relays in the front of the panel seemed loose, so I pushed them down. Took the car for a 10+ mile drive, and it ran fine.

Note- it is no longer raining.

I think I might keep an eye on the problem; if it recurs, I will get to work testing things (relays, starter fluid, tune-up stuff, etc)

[yellowline]

CJ, it used to idle horribly and even die on idle when it needed an O2 sensor. Even though that wasn't a rain-only problem, perhaps you could look into that? Maybe it's a bad connection at some point in the O2 wiring?

The pump relay was changed just a couple years ago. Not sure if it's as widespread a problem as it is on 944s; that relay was over 15 years old when it went.

I would hope it isn't the HG!

[notfarnow]

If it was raining both times it happened, I'd be willing to bet my Nanny's life that it's just spark plug wires. Next time it happens, soak them with wd40 and see if that helps. If it does, replace the wires and distributor cap.

[Porsche_monkey]

The 740's have two fuel pumps IIRC. Low pressure, then a booster. When the pumps go for a dump the car runs poorly, or not at all, espescially when low on fuel, i.e. below 1/2 tank. This was a common problem.

I would get the fuel pressure checked if this continues AND it is not weather related.