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1990 240 hard start when cold

S

scribbler

New member
Joined
Jan 9, 2026
Location
Maine
I've recently bought a 1990 240 DL with a normally aspirated 2.3 and an automatic. I have not driven the car because it needs an exhaust (it's loud), but I occasionally start it up. Most of the time it starts and idles well, but tonight it was hard to start. I needed to crank it for the better part of a minute before it showed signs of catching, and when it did start, it felt like it was running on one or two cylinders -- I had to rev the engine before all four cylinders kicked in. The air temperature was around 32 degrees. I've searched the forums, but haven't seen a problem just like mine. Where should I start diagnosing? I don't want to just start throwing parts at it.

BTW, the seller was driving the car regularly, and told me it had sometimes been difficult to start, but not always.

Thanks for whatever help you can offer!
 
I had written something out last night and decided not to post it because really it could be too many things to cover in a post. I'd start at the coolant temp sensor, it sounds kinda like an intermittent CTS issue. Do you have any stored check engine codes?
 
Try the special Diagnostic Test Modes 2 and 3 as described in the below link, then report back:

Engine and OBD Diagnostic Codes<

Volvo Engine and OBD Diagnostic Codes<
www.volvoclub.org.uk

If all tests good, pull the vacuum line on the FPR fuel pressure regulator and check that it's dry. After ~10 seconds of failing to start, pull a spark plug and post a picture of it (you'll need to resize the picture to less than 1MByte first).
 
Thank you both for the help! I've done the diagnostic tests, and found no codes stored (1-1-1). Following my Haynes manual, I checked fuses 4 and 6, for the fuel pump relay and the pump. The fuses weren't blown but the contacts were corroded, so I cleaned them up. I had a friend turn the ignition to the third position while I listened for the sound of the in-tank pump at the filler -- I heard nothing. So now I'm suspecting that the pump is bad, or there's a wiring issue. I'll check for 12V at the connector next.
I'll pull the vacuum line on the fpr and report back. The engine started this morning after about 5 seconds of cranking, but certainly wasn't running well.
 
Here's my report. There was no power getting to the in-tank pump with the key on, so I unplugged the pump relay and jumped the red and red/yellow wires. That made the main pump under the car run constantly, but not the in-tank pump. However, there was now power getting to the in-tank pump. So it looks like that will have to be replaced.
bobxyz, I pulled off the vacuum line at the fpr and found that it was wet inside, and smelled like gas. Looks like I'll need one of those, too.
I tried starting the car this evening -- it would fire up for a couple of seconds, and then die. Repeated crankings produced similar results. I removed a spark plug after trying to start the engine -- photo attached.
 

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One further update: I removed and plugged the vacuum line to the fuel pressure regulator, and reinstalled my (faulty) fuel pump relay. The car then started and idled -- not well, but it ran. I think I'm on the right track here. As I understand it, disconnecting the vacuum line from the fpr causes it to go to full-rich mode, is that right?
 
Thanks, Overdrive. On my car, the yellow/red wire is the hot wire. There's power at the connector when I jump the fuel pump relay, so if there's a break, it's between the connector and the pump itself.
 
scribbler said:
One further update: I removed and plugged the vacuum line to the fuel pressure regulator, and reinstalled my (faulty) fuel pump relay. The car then started and idled -- not well, but it ran. I think I'm on the right track here. As I understand it, disconnecting the vacuum line from the fpr causes it to go to full-rich mode, is that right?
Click to expand...
Good progress! When working correctly, the LH2.4 ECU in your car should turn on the fuel pumps briefly when you first turn the key to run (before turning it all the way to crank/start). You should be able to hear the fuel pump relay click, and the pumps run briefly.

When working correctly, removing the FPR vacuum line makes the fuel pressure at idle go from ~35psi to ~45psi, so ~30% rich. Having a fuel leak in the vacuum line makes it even richer. This would explain the wet looking plug and difficulty starting.
 
Thanks, bobxyz! When I turn the key to the third position, I hear the relay click, but I don't hear either fuel pump run. When I jumped the red/yellow and red wires at the relay connector, the main pump under the car ran continuously, but the one in the tank was silent.

My plans call for driving this car about 10 miles to a muffler shop tomorrow morning -- is there a reason I shouldn't?
 
If you need an un-damaged catalytic converter, you shouldn't be driving it when running really rich. The extra fuel can also wash down the cylinder walls, removing some of the oil needed for lubrication. If it were me, I'd replace the FPR before driving it anywhere. I'd also smell the oil and change it if it smells of gasoline.
 
I put off driving the car, and was able to get a new fuel pressure regulator today, which was simple to install. The car is now starting much more easily and idling better (but still pretty loud with no muffler!). The oil seems fine, though I will change it soon since I don't know how long ago it was last changed. Thanks to everyone for your help!
 
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