'91 240 DL Acting Strange

typ · Post by **typ** » 09 Jul 2007, 17:50

Hello all,

I have a 1991 240 DL that from time to time refuses to start... It has a brand new battery, new alternator, and fresh spark plugs. Usually when I have power problems I can test the amount of energy by rolling the power windows up and down (usually lights will dim and pinging door sound slows to a dying groan...). The car has plenty of power, I can run the wipers, the windows, the A/C with no problems. When I turn the key, nothing happens. The engine doesn't even try to turn over. I've checked fuses-they're fine.

This happens to me about once ever 3-4 weeks and I'm able to fix it by having it jumped by a friends car---just like that with no problems. It will run fine for the next 3-4 weeks until it sporatically decides it doesn't want to start. Any ideas? How can a car that appears to have plenty of charge be started instantly by a jump?

All help is greatly appreciated!!!

Thanks you,
Patrick

CarVolvo · Post by **CarVolvo** » 09 Jul 2007, 19:14

i would check the ground wires and power wires to the starter motor. If you dont get anything turning over its usually because of that.

I think it might be your solenoid..which is the part which makes the gear connect to the fly wheel to start it.

markvt · Post by **markvt** » 11 Jul 2007, 21:31

Another possibility is a faulty neutral safety switch if it's an automatic. When it won't start, try holding the key in the start positon and jiggle the shifting lever. If it starts you can be pretty sure it's the switch.

CarVolvo · Post by **CarVolvo** » 13 Jul 2007, 08:45

good point on the neutral switch!

If it happens again put the car in neutral and try to start it.

klojbg · Post by **klojbg** » 18 Jul 2007, 13:38

I agree with the soleniod being the problem, or the wiring to it. assuming the battery is good and at full charge. The fact that jumping will start it means to me that the jumping source is at a higher voltage, ie. the engine running generating 13.5 to 14.5 volts as opposed to the 12=12.5 volts at rest. As 90+ percent of electrical problems are due to "bad" connections I would start there.

wojeepster · Post by **wojeepster** » 18 Jul 2007, 15:25

sometimes the electrical part of the ignition switch goes bad. You can measure the voltage at the ign side of the coil with a voltmeter when cranking. I think black/red you should get 12v with key on.