Engine quit running

240 · Post by **240** » 02 Mar 2012, 15:24

My Volvo is a 1991 with about 108,000 miles, automatic transmission, a/c, "red" engine, LH 2.4 fuel injection.
Yesterday, while driving home from work late afternoon, in moderate traffic, I drove about three miles and then waited at a stoplight for about one minute. When the light turned green, I turned the corner, and had to stop for another light about one block ahead. I was stopped a few seconds at idle when the engine shuddered briefly and just stopped. That event lasted about one second. I immediately restarted it without incident and drove home.

My fear is that something is wrong and this will repeat, and possibly not restart.
Years ago, I had a fuel relay fail in traffic.

Here are my questions:
What are the two or three most likely causes of it quitting like that?
Is there any way to check the fuel relay's performance?
Would it be a good idea to carry a spare relay?
What do you make of the shudder? I do not recall a shudder when I turn off the engine with the key.
Is this more likely a fuel issue or an ignition issue?
What (if anything) would you do if this happened to you?

Last year, I changed the spark plugs. I still need to change the cap, rotor, and possibly the secondary wires.

Post by **billofdurham** » 03 Mar 2012, 11:38

What was the outside temperature, cold, warm or hot?

What was the engine temperature?

Stopping with a shudder I would be looking at a fuel problem. Possibly the relay, but as it started up immediately this is unlikely.

You can't check the fuel relay's performance but you can open the relay and check to see if any of the solder joints are cracked.

If you manage to print the instructions for the OBD run a check to see if any fault codes are stored and let us know the results.

Bill.

240 · Post by **240** » 03 Mar 2012, 22:37

Thanks, Bill for your comments. The air temperature was about 70 degrees. The engine had about three city-driving miles to warm up, so I would call that warm. Adding to my original write-up, I drove home about five additional miles that day, mostly at freeway speed, with no symptoms. Oh, and the gas tank was nearly full.
This morning, I checked the OBD and there were no codes. Today, I used the car for my normal saturday errands and there were no symptoms.
Several years ago, I was alerted that the crank position sensor (CPS) could fail. Could that be the culprit here?
Is the CPS, should it fail, something that one could repair on the road?
Another related question - I can start this car only when it is in "park". It will not start in "neutral". Should I be able to start it in neutral? Would be nice in the event the engine quit while driving.
Could a clogged fuel filter be the cause?

Post by **billofdurham** » 04 Mar 2012, 12:53

We now all hope that it keeps running and was just trying your patience when it decided to stop. Cars are well known for doing this.

Moving now to the serious side I think what you were warned about is the impulse sensor which is located in the top of the gearbox bell housing with the wire running up the back of the engine. They are known to cause problems if the insulation breaks down on the wire. It is easy to check by feeling the wire, with the engine cold as it tends to get warm down there. If you feel anything out of the ordinary you should take the sensor out, one screw holds it in place, and check the insulation carefully. It is not a good job to repair at the roadside with a hot engine.

How long is it since the filter was changed? It would cause problems if it were clogged but as you have the car running again that seems not to be the case.

The reason I asked about the amount of fuel in the tank is that you have two fuel pumps, one in-tank and one main under the car. The in-tank is a priming pump for the main which can cope on its own if the tank is more than half full but does struggle without the priming pump once the fuel level falls below half.

It should start in Park and Neutral. The neutral safety switch may need adjusting as in the attached.

240 PNP switch.pdf: (208.77 KiB) Downloaded 152 times

Bill.

240 · Post by **240** » 09 Mar 2012, 14:36

Thanks, Bill, for your comments. I will chalk up this incident to an older car "trying my patience", as you say. It has not recurred, thankfully.
However, I would like to be as prepared as I reasonably can. For me, this means carrying parts that could possibly fail.
I intend to obtain a new fuel pump relay, part number 35 23 608 - also referred to in the Bentley Publishers "one-size-fits-all 83 to 93" manual as "217 main relay, LH system". It shows this behind the glove box. I am guessing this would be an easy fix, if necessary, on the road.
Now it gets confusing, and this is where I need expert help.
The manual also shows the following:
1. a "216 fuel pump relay, LH system" right next to it behind the glove box.
2. a "212 LH fuel system control unit"
3. a "214 LH fuel system fuse"

I heard there is a part called a "suppressor relay" which can fail. When I called the stealership, I was told this is called an injector relay, part number 1323592, and that it is found under the hood, on the driver's side. If this failed, could it cause a breakdown? If so, I'll get one. If its only to suppress ignition noise for the radio, I won't. Is this just another name for one of the items listed above?

My question - which of these items would you recommend I carry in the car, just in case.

Post by **billofdurham** » 10 Mar 2012, 12:13

Bentley's isn't always correct. The fuel system relay is behind the glove compartment as is the fuel system control unit. However, the fuel pump relay is under the driver's side of the dash, as on the attached.

1991 240 relays.pdf: (178.79 KiB) Downloaded 269 times

That is the only part I would carry, if I were to carry any of them. It can be changed easily at the roadside.

The 240 doesn't have a radio suppression relay. This was a misnomer in any case. It was a fuel injection relay fitted to the 740 because without it the injectors were interfering with the radio.

Bill.