Hello,

We have a 1983 Volvo 240 DL wagon that recently developed a problem starting. It would have to turn over a long time before it would get going. Two weeks ago, while it was idling at an intersection, it stalled and would not restart.

The local mechanic thought the most likely cause was a fuel supply issue, and we have now replaced the following parts without any improvement:

Fuel pump
Fuel sending unit
Fuel filter
Relays for the fuel injection system
Spark plugs

The mechanic reports that the car has spark and excellent fuel pressure, so it's hard to imagine why it won't start.

If anyone has encountered a similar problem or has suggestions about things we can investigate next, I would be very grateful for the advice. Compared to more modern cars with lots of electronic modules, one would hope that there are a limited number of potential causes for this continuing problem, now that we already have replaced the suspected problem parts.

Thanks,

Andrew

 

I believe your Crank position needs to be replaced if it did not restart. Have it tested first and perform obd1 diagnostic
Hard starting would lean towards Fuel pump check valve... But not a no start!!!

Goldenblock
Senior member

 

Thank you for this suggestion. I will ask the mechanic to check the crankshaft position sensor and, if he can't figure out how to test it, we will replace it.

Based on some further research I did, it appears that the ignition control module also could be a potential cause of a starting problem. I will ask the mechanic to check that as well, unless you think it is unlikely to be the cause of the problem.

Thanks again!

 

Your '83 will not have the crank position sensor nor an OBD diagnostic. That started in '89 with the LH 2.4 fuel injection system. My guess would be with the fuel injection relay. Check this link for diagnosing fuel issues: http://cleanflametrap.com/transferPump.htm

 

My mistake I thought it said 93 yes 83 won't have it!
Proceed with the ignition module

Goldenblock
Senior member

 

Thanks again. The two relays for the fuel injection system were replaced in the last 3 months, and the car was running after the replacement, so I think those are likely okay.

The mechanic said that two of the cylinders were soaked with fuel when he went inspect the fuel injectors. So we are going to replace all four injectors and the fuel pressure regulator as the next step.

 

You should stop randomly replacing parts. It gets expensive and frustrating. and if you have spark - it's not your ignition module.

You have spark (I trust at a/the spark plugs) and you have fuel pressure (I trust a fuel pressure gauge has been installed to measure that.)

You have two wet cylinders. Has the cam timing belt been checked for correct alignment? We know the belt is there and spinning (the distributor has to spin to create spark)

Certainly injectors have stuck open - but it's not a common occurrence and it's unlikely that 2 will fail at the same time. Has a noid light been used to check if the injectors are firing?

If you think the cylinders are wet because injectors are stuck open - before replacing them on a guess - How about pulling them and the rail off and inspecting them? (Try to start the engine and watch the injectors spray) Fuel pressure regulators do fail - but have never seen one fail while driving. They usually send too much fuel when first started (and foul all the plugs) in the morning then settle down to the correct pressure. The only way I could catch them malfunction is to have a fuel pressure gauge connected the night before and start it the next day. Your previous hard starting - If it was worse when hot that could have been a bad fuel pump check valve. (there's an easy test for that, but now you have a new check valve in your new pump. It is possible for the fuel pressure regulator to leak down, again not common. But easy to test with a fuel pressure gauge and a clamp on the return line)

1983/84 had a really bad engine wiring harness. We replaced many on cars less than 15 years old. Wires rub together and all sorts of weird things happen - (there's wiring to the starter/alternator in the same harness with the injector wires) When was yours replaced?

 

Thank you very much for this very detailed set of troubleshooting suggestions, which I have just passed along to our mechanic.

The issue about wires rubbing together jumped out at me because last summer I was having a weird problem with the headlights. Only the high beams would work on one side and only the low beams on the other. I thought maybe some bulbs had failed. I'm no mechanic, but I figured that, since there were 4 bulbs, I could verify which bulbs were working by moving them around. It turned out that the bulbs were fine, but there was a short in the wires, and by moving the wire an inch in one direction, the problem was fixed.

Anyhow, the engine wiring harness has never been replaced. Would you recommend removing the wiring harness and checking all the wires for conductivity, or is it the rare situation where you would just replace it given that its been in there for 50 years?

Thanks again for taking the time to share your expertise.

Andrew

 

Before you take recommendations from has been mechanics to dismantle your entire wiring harness!! please be certain... If your car was running before it won't lead to a random no start out the blue.


Test test test
Continuity
Resistance etc
Injectors
Fuel pressure

Goldenblock
Senior Member

 

I'm not suggesting even touching your wiring harness - it is a problem I saw many times fixing Volvos. The 83-84s seem to be the worst with the insulation falling apart.

Your engine wiring harness has been baked into a solid mass. (the plastic sheathing becomes hard and brittle) After about 15 years the only way to get them off the engine was with wire cutters.

So - no, do not try to remove the harness. (if you do it will be destroyed)

Replacing it - is there a replacement available? There were aftermarket solutions a few years ago - but that kind of thing is usually very expensive. The factory harness was close to $1000 when it was available.

This guy might have a solution if you need a harness.
https://www.prancingmoose.com/volvoh..._240_non-turbo

 

Thank you for the additional guidance, hoonk.

Based on your explanation, it definitely does not make sense to try to remove the entire wiring harness. Should I ask the mechanic to test the wires going to the fuel injection pump/injectors and/or the starter and alternator? I'm not clear, and suspect the mechanic may not be clear either, on how best to detect whether there is something wrong with the wiring, other than trying to move the wires around and see if it results in a loss of connectivity or a short.

Thanks again!

Andrew

 

The insulation on the wires in the plug shown below is usually the first to fail - what do those wires in your car look like? (plug is above the cam cover)

 

Good morning,
I stopped by the shop yesterday and took these photos of the main engine wiring harness at the connector. The insulation on the wires looks pretty intact to me. I did not detach the connector or try to peer into the plastic covering that holds all the wires together on each side. I guess it's a possibility that the pins in the plug (or some of them) are not making a good electrical connection.

 

Looks like that harness has been replaced. I thought the factor harness had a grey plug on it - your looks black. Those wires are for the alt light, temp gauge, oil light and a couple of other things - The fuel injection wires are in the harness also - but terminate at the control unit in the rf passenger compartment and protected from the environment. .

 

The original shop, after replacing numerous parts as described above, was unable to do any further testing to identify the reason our Volvo 240 would not start. Accordingly, we had it towed to another shop that has a technician with a good deal of Volvo experience. I was not aware of this mechanic when I selected the first shop.

Anyhow, after about 15 minutes of testing, he determined that the coil was not working properly. He replaced the coil, and now the car is running great.

I wanted to provide this update, and also to thank everyone for all the tips about things to check.

 

I'm glad we were able to assist my brother!
If you need any parts
Hit me up at
L&D Volvo redblock parts
Atlanta Craigslist
Shipping nationwide

 

any updates ?

 

See my previous post of August 24.