My daughter just bought a 1990 240 DL to go to school in and absolutely loves the car until this morning We changed the oil in it yesterday and fixed some lighting issues and then this morning she went to start it and nothing. The car turns over but won't start. So what I have done so far is, pull and clean the spark plugs, check the pressure of the fuel pump (100 psi). Like I said, it turns over and seems to try to catch but never rumbles to life. Any ideas would be greatly appreciated.

Thanks

 

unplug the mass air flow sensor. if it starts replace the mass air flow sensor.

could actually be a number of other issues. spray to ether down the throttle body and try starting it right afterward, that would eliminate the ignition.

There are 2 fuel pumps. one for starting (prepump) another that takes over once the engine is running.

there is a relay under the passenger side dash for the fuel pumps. also check the fuse by the battery.

It may be possible you shorted a wire somewhere. Inspect all areas you were in.

 

Lifesgoodhere, thank you for your response. Well I unplugged what I believe is the mass air flow sensor and nothing changed. The 25 amp fuse is not blown so I moved on to relay under the glove box and not sure of what I am looking for. I haven't tried the ether trick yet. But I do have one thing that I am unsure of...When the key is in the run position, the fuel pump continues to run. Is this normal or should it cut out at some point? Oh and one thing that I forgot to mention in the beginning is that the park lights were left on over night and the battery went dead so I have been trying to charge the battery with a battery charger. I can't imagine that this led to the non-starting engine, but strangers things have happend.

 

Next step is to check for codes : Engine and OBD Diagnostic Codes Read the whole thing. Especially Diagnostic Mode 2, System Sensor Test.

Be aware that a 131 or a 214 code indicates no signal from crankshaft position/RPM sensor. This is the only sensor that does not have a "limp home" mode, and if a signal is not received from it, the car will absolutely not start.

 

When something like this happens, I tend to look at the most recent work I did. Your car has an ignition unit on the driver's side front inner fender by the air box that can cause a no-start. See if you disturbed some wiring. Also, the 240 has an open fuse holder near the battery that will keep the car from starting. So close to the battery, fumes do the holder in quite often even when the fuse has not failed. First things first, though...check the codes.

 

MAF should not come into play after a few seconds of running, so that should not be the culprit.

No doubt, check the codes, but that fuel pump should not continually run after turning the key in the "run" position. I'm not exactly sure if the pump runs until the system is up to pressure, or if it just runs a short while no matter what. Maybe you ruptures a FPR? My guess is the Fuel Pump relay is shot. It is white, and under the passenger kick panel like said before. Is is rectangular if that helps. Did you remove the plugs after you cleaned them and tried to start it again? Are they wet, dry?

 

Thank you all for your willingness to help. Well when I pulled the plugs they were wet. Cleaned them all up. Then started checking all the wiring that I may have hit while trying to fix lights and what not. Then when I tried the ignition one last time for the heck of it, the stupid thing rumbled to life. Not sure what I did, but am a little happier that it is running once again.

 

wet plugs usually means it wasn't getting any spark. some electrical connection was probably loose around the ignition control unit, and when you wiggled it again, it got less loose.

 

Well it happened again, the car quit running yesterday. I found the problem and fixed it I wiggled a wire while my daughter was trying to start it and found that the crank position sensor was in terrible shape so I replaced it and Waaaaaa Laaaaa.

 

That's great! Explains the wet plugs. If the ecu sees no rpm signal, it will not fire the injectors. I think we are seeing the lifetime of crank sensors come about these days. Ten years ago, crank sensors were not a leading cause of no-starts here at the shop but it seems increasingly, it is the cs that has failed. Luckily, like most things under the hood of an rwd Volvo, they aren't terribly difficult to replace. Seems the long pig tail on them gets beat all to heck behind the head against the firewall with bad transmission mounts too.