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My girlfriend has a mid-80s 240 that she bought used last month. I noticed that there seemed to be an alarm system installed but since we had no information on it, and it didn't seem to do anything, I assumed it was disabled. Today I removed a battery cable to clean the contact, and when I replaced it, to my surprise the alarm triggered! Turning the key in the ignition does not turn off the alarm, and now the car won't start. I have disconnected the battery again (for the sake of the neighbors) and don't know what to do next.
She doesn't want the alarm at all so I suppose my question is: How do I bypass it and get the car running again?
Thanks,
Simon
Answer -
The first and quickest thing to do is disable the alarm speaker. It will be somewhere under the hood, and look like a fog horn or loud speaker. You can just clip the wires going to it to stop the noise. Later, trace the speaker wires back to whatever electronic equipment makes up the rest of the alarm, and remove the whole thing. Good luck!
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Hi Jason, thanks for the tip. Here's my next puzzle. The distributor stopped sending sparks to the plugs so the car wouldn't start. There is current available to the distribot but none is passing through.
I took it to a mechanic and he said the sensor inside was probably bad. It's not clear to me what this sensor does but it supposedly talks to the engine. The replacement (rebuilt) would be $275 so I got a junkyard part that he put in. He says the car started for a few seconds and then died. No more luck there. So I got another junkyard distributor, the engine started for about 5 minutes, and then died. He believes that all the distributors were bad. Do you think the car is somehow killing the distributors? Should I continue to find junkyard parts and swap them out until something works? Why does the distributor talk to the computer? Can you think of any other possible problem here? Apparently the computer is OK. OK Computer.
Thanks,
Simon
p.s. Merry Christmas!
Answer -
The distributer talks to the engine computer using the crank position sensor. As the distributor rotor turns around while the engine runs, it inherently gives the stroke position of each cylinder, a key piece of information so that the injectors know just when to spray gas in the chamber. If that sensor breaks, then the injectors don't know when to spray, causing issues starting. Sometimes it won't start at all, sometimes it will barely run. Those sensors do go out, but I doubt they were all bad on the multple replacements you got from the junkyard. My question is have you only been replacing the distributor cap? If so, there might be a problem further down in the distributor itself, possibly with the position pick up gear at the very bottom. If it hasn't been done already, remove the entire distributor and give it a careful inspection. I doubt there is a way for the car to "fry" the distributor cap, so it is probably a problem further down in the distributor itself. Good luck!
Hi Jason,
Thanks for the quick response! I have actually been replacing entire distributors, not just the caps. The ultimate problem is that they aren't delivering sparks to the plugs, although the coil seems to be doing its job (i.e. delivering current to the distributor). So it's something inside. The bevel gear at the bottom has looked good on all three.
Anyway, if you have any epiphanies, let me know. Otherwise, thanks for your help and have a warm winter.
AnswerI'm suprised to hear you've been replacing the entire distributor. First thing to check is that the rotor head is actually moving at all. Take the cap off and crank the engine. Does the rotor move? If it doesn't, then there is a problem with the feed gear down inside the block that normally turns the distributor. If it does rotate, then check for burning or melting around the rotor or cap pickups. Anything that looks abnormal? If all is ok, then I would start looking at the wire from the coil and the coil itself. The distributor is a fairly simply device, and as long as it is moving, you should be distributing the current, even if the sensor hasn't worked on all three replacements. How have you measured the voltage from the coil? If it is there but too low, it might not be enough to be properly distributed. I would probably grab an extra coil at the junkyard and a few wires and start trying different combinations. Good luck!
