Hello,

I've got a 1988 Volvo 240DL. Recently had the motor mounts replaced so the engine is sitting differently than it did before. That's the only thing that's changed.

Tonight the car shut off on the freeway (SCARY). Pushed it to the side, sat around for a while, messed with some fuses, etc. It started again! Wow. So we drove off the road. In a mile, it died again. Messed with some fuses again, ok, hmm, nothing really, then it started again! Drove a while, it died. We hung out, then it started again. etc etc etc. It happens.

It must be electrical, correct? What could I check? By the way, it's been really rainy here lately, but wasn't raining at the time.

Any ideas?

 

I would check to see if the fuel pump relay is getting hot when you drive. They can cut out if they get too hot when they are defective. Then I would check if the in-tank pump is operating. Listen through a length of hose through the filler tube while the car is running. I had a VW Fox that died just like that when the in-tank pump went out although it was stinking hot summer when that happened. Also check the fuel filter to see if it is clogged. Check to see that there is no dampness in the distributor cap. Check all the connections at the coil and your plug wires. Couldn't hurt to put a bottle of heet or other fuel dryer in the tank just in case you got some watered fuel.

 

I'm kind of stumped. I checked the fuel pump relay. It clicks so I assume it works. Oddly enough when the car runs i can unplug the relay and the car still runs. Dunno what's up with that. Also I forgot the fuel pump relay is new. Replaced it when I replaced the fuel pump. I jumped the fuse wires 4 to 6 and the pump runs. I have no in tank pump. It failed and I haven't replaced it. Been years I think it's fine.

I have spark so this is a fuel issue.plugs are dry too.

Checked for distributor cap moisture. Found none. Kinda at a loss.

That one fuel fuse up near the battery has failed in the past. The plastic fuse holder is all burnt and corroded. Maybe it melts and shorts out? I'm gonna jumper the wires to find out.

 

Could be many things. The clue is that operating the car creates the condition necessary for it to shut down.

I know NOTHING about your car but off the top of my head I can think of three things that would behave like this.

1. Carb icing. Carb ices up, engine quits, ice melts. Repeat.
2. Faulty ignition coil. Car runs, coil gets hot and fails. Engine stops, coil cools down. Repeat.
3. Fuel tank vent blocked. Fuel pump pulls partial vacuum in tank, fuel flow stops, engine quits, tank pressure slowly equalizes. Repeat.

It may be something like that. I'd also be thinking about your engine mount replacement and looking for any electrical wiring or connectors or anything else that may have been damaged when the engine was jacked up and down.

 

Thanks for the reply. It's not icing (California). Could be ignition coil, how would I use a multimeter to test that? Wouldn't a bad coil produce no spark? When the engine dies I still have spark. I was thinking about wiring too, but it seems a short would be more constant and not so predictable time wise and engine heat.

What can I do about the fuel vent thing?

 

To be honest I wasn't proposing those three things as potential causes of your problem, just as examples of the kind of thing you should look for.

Carb icing in aircraft engines can occur at ambient temperatures as high as 100F with high relative humidity though it's more common at lower temperatures. Does your car even have a carburettor? Clicking around I can see it probably does. Why don't you find out if your carb is heated (may be the inlet air that's heated, not the carb itself) and if so whether your carb heat was somehow compromised when the engine mounts were changed.

There are other carb-related problems that could cause your engine to quit. Fuel level in the carb, for example.

The ignition coil thing happened to me decades ago - not on a Volvo - which is why I suggested it. The fuel tank vent problem is not very likely and I don't know where the vent is on your car though it's often in the gas cap.

If you still have spark when the engine dies I'd be thinking some kind of carb problem. I wouldn't totally exclude carb icing as you said it's been really rainy - i.e. high relative humidity - and carb icing would do exactly what you experienced, but you need suggestions from someone who's familiar with 240s and I'm not.

 

It's the fuel pump relay. I had messed with it years ago and it was hiding in a different spot than where I expected. I was examining the overdrive relay.

Problem solved!

 

Well there ya go. Good job.

 

migbro, these cars have electronic fuel injection, not carburetors. fuel tank ventilation on virtually every car made since the early 1970s involves a charcoal cannister.

akpasta; just because a relay 'clicks' doesn't mean its working.

 

As I said, I know nothing about 1988 240s but was just trying to get the OP thinking constructively about his problem. 1988 seems like the stone age and as far as I could tell some 240s did have carbs after that date. Here's a thread on one with the B230K engine.

Is that picture you, btw?

 

the B230K was never sold in the USA, all Volvos since the mid 70s have been fuel injection here in the USA..