I am a new member, so forgive me if I am posting a problem which has been discussed before.
I own a 1993 Volvo 240. It is in great shape, but it has one very annoying problem. If I drive the vehicle and park it for about a half hour it is very difficult to start. I have to keep cranking the ignition for two to three minutes nonstop for it to fire. If I give it any gas at all during this two-three minutes it will not start at all. I saw some postings suggesting the symptoms might be related to the engine crank angle sensor or possibly the fuel pump relay or the MAF sensor. Any suggestions? Thanks!

 

It is hard to say why your car has this difficulty. are you literally holding the key to the start position for 2-3 minutes? This will destroy your starter at a minimum. I guess the first place to start looking would be the battery. Have you tested it? How are the connections? Do you have tools and work on cars, or are you looking for a diagnosis. An issue like this requires testing.

 

the crank position sensor on the LH2.4 cars (1989+) is definitely one possible cause of heat soak no-start problems. but so is the fuel pump relay, a old and tired fuel pump, and various other things.

and yeah, you should never crank for more than 10-15 seconds at a time, or the starter will overheat and die.

 

A little diagnosis is in order. The next time it doesn't start, first check to see if the fuel pump is running. When you first turn the key to the II position, you should hear the main fuel pump run for 1-2 seconds and then shut off. If you don't hear it, then most likely the issue is with the fuel pump relay which is located under the dash on the passenger side behind the glove box.

If the pump runs but you still can't start the car, then the next thing to check is the crank position sensor. It is located on top of the bell housing where the engine and transmission are bolted together. There is a thick black wire that runs from the sensor up to a connector on the firewall. Check this wire. Wiggle it around and then try starting. If the insulation is flaking off of the wire, you need to replace the sensor.

Most likely, as Pierce stated, it is one these two items.

 

I've had the same condition with my '89 240, and got here looking for understanding of the issue. This morning I found that leaving the key in the II position for about 8 seconds I will hear the click from the fuel pump relay area at the glove box and it seems the blower fan starts as well, but the engine will start every time. I wait the 8 seconds to hear the click and low sound from the blower.

 

Henry, that almost certainly sounds like a funky fuel pump relay, unless its bad wiring.

 

Every time a Volvo will not readily fire up after sitting for a time, and having started fine when cold, the first thing I'd address is the Fuel Pressure Regulator.

 

fwiw, I've had more fuel relay and fuel pump problems (3) than fuel pressure regulator (0 to date). this is on 3 redblocks that have about 1 million miles between them.

 

Well, your sample is a little limited but, yes, generally that's true... However, to get a little more nuanced, when the car starts well, but after a short stop, say 10-45 minutes, it has a tough time starting, the FPR is often the culprit... I won't bet the farm but it is the first thing I'd look into given the symptoms--much easier than doing a pump, no?

 

Pierce, Thank you for this post. My daughter's 1992 240 had inconsistent starting problems. I hadn't even thought of replacing the crankshaft sensor. Did it and that solved the problem. Now it starts like it probably did when it was new. The one I replaced had several cracks in the casing around the wires. I am again the hero to my daughter! Thank you.

 

Pierce, Thank you for this post. My daughter's 1992 240 had inconsistent starting problems. I hadn't even thought of replacing the crankshaft sensor. Did it and that solved the problem. Now it starts like it probably did when it was new. The one I replaced had several cracks in the casing around the wires. I am again the hero to my daughter! Thank you.

 

Is the crank sensor also called the neutral safety switch? That's what the part was called that I had replaced when car wouldn't crank.

 

Nope, that is another sensor altogether and in different location. The neutral safety switch should not even let car crank over I believe.

 

In my almost 40 years of tending to these cars I have found 2 tools that are invaluable for diagnosing there systems. One is a test light. Next is a fuel pressure gauge. You may have a bad fuel return check valve. It is the fitting that is in the end of the main pump. Be careful of the pipe that connects the pump to the filter, they like to break.