Hello, new here. No experience with Volvos, but plenty experience in the automotive repair field.

I have just recently purchased a 1990 Volvo 240 DL sedan.

1990 Volvo 240 DL that won't run
I got it from my boss for practically nothing because it won't start. I am making this post because following the advice from other threads with the same or similar issues has gotten me nowhere.

The previous owner had replaced a ton of parts trying to fix it before giving up. The list of parts he replaced that he gave me were:
Injectors
Spark plugs
Ignition coil
Ignition control module
Crankshaft position sensor
ECU
Fuel pumps
Fuel filter
And replaced timing belt
He also said that there were no codes on the diagnostic module. But nothing worked.
I bought the car thinking it would be a little simple thing he overlooked. Boy was I wrong so far.

I have replaced:
All the fuses (and cleaned all the contacts of corrosion)
System relay
And the plug wires

Now to the diagnostics I have done. The car cranks just fine, but will not run. It will sputter on one or two cylinders for a moment and backfire. I checked the firing order and it was correct, but discovered the wire to the distributor from the coil was bad, so replaced the plug wires. Same issue. I checked the timing of the timing belt was correct, and all the timing marks lined up. I used an inline spark tester and it showed a good spark. I hooked up a noid light to the injectors and got nothing. I followed the wiring diagram from Alldata and tested the wires to the injectors from the ECU and relay and they had good continuity. I checked that the ECU was receiving the engine speed signal, and confirmed it was. I checked codes myself, but only got a solid red light instead of any codes. When I opened the oil fill cap it smelled like gasoline. Reading other posts the ECU could be bad then, but I'd like to not spend a ton of money yet if I am not absolutely positive of that being the issue.

Everything I have done has got me no closer. Any advice or tips would be appreciated.

 

From what you have tested I would suspect the ECU is bad. However, just for grins and giggles I would spray a shot or two of starting fluid in the air intake and try to start. If it starts or runs for a second or two, you have a fuel delivery issue. If no start or sputter I would suspect a spark or timing issue. I'm thinking spark or electrical since you don't seem to have an injector pulse at the injectors. Is there no injector pulse at all the injectors or just one or two? Either way, the starting fluid test is cheap and easy. Look at it this way, with all the parts replaced so far, once it is fixed you will have a practically new fuel and ignition system!

 

I tested all 4 injectors and none of them have a pulse with the noid light. I don't have a helper most times so it would be difficult for me to test voltages. But someone else mentioned to me it could be high resistance in the injector wires, since they all seem to share several points in the wiring that I may have missed when I tested resistance.
The previous owner did replace the fuel injecton ECU, but he told me he bought it used so it may have also been bad. I'll try to get some starter fluid and see if it runs off that. Then also try to see what voltages I have at the injectors while cranking if I can figure a way to do that without help

 

I agree about the bad ECU. You can find them used for $100 or so. But, it's interesting you got a light -instead of nothing and the signal is received. I've never had to replace the ECU, so I'm not sure how hard it is?? I doubt it's hard. I think 90s are notorious for ECU problems. They must have fixed it for 91.

Without the ECU working, I don't think the ignition will work. Check out this thread: https://volvoforums.com/forum/volvo-...roblems-58973/

"The ECU uses the signal from this sensor for timing the ignition system. Without a signal on this, the engine will not generate spark."

We have a 91 240. Had similar start problems for a long time. Check the MAF. Clean it or replace it. Won't hurt anything, and it's always a plus.Trying to think back to where we started when we got him seven years ago or so?? I seem to remember some battery and fuse issues first (fuse 6 for fuel?) the MAF was replaced. I also remember replacing the starter early on. I replaced all the fuses first thing.

Keep posting. You will sort it.

Heather

 

The part about the spark not working if the ECU is bad is what I keep hearing and reading, but I've tested the spark multiple times with an inline spark tester and it has spark. Not the strongest, but it is firing. but Every single time I test the injectors with a noid light it doesn't light up at all. I still need to test the injectors with a multimeter to see if it gets any voltage to them. There may be high resistance in the wires I didn't find before. It's been really hot out and too muggy to be out working on the car the past few days so I haven't done anything to it in a while.