QuestionKevin - Alittle recent history on this car:
First problem was occasional dropping rpms on the tach at all speeds. When the mechanics got it (3 different shops including Chrysler) it would start and then just very quietly stop dead. Sometimes it would start or restart the first time, sometimes I'd wait 5 minutes and then start. Sometimes it would stop and start 3 or 4 times and then not start on the first try. My son put a new map sensor.
Haven't been able to drive it much since because after he put in the map sensor, I drove it about 3 miles and something under the car - not the engine - "lurched". This issue I think has been slowly developing over the last year, as it has had what I would call an occasional mild "catch" or a "skip" you could feel somewhere under the front end. #1 son tried to install a crank sensor the other day - and succeeded - except that now the engine doesn't turn over - I get nothing except a feeble seatbelt light when I turn the key. When I locked it from the inside door the first time, the security light didn't come on and the car wasn't locked. Tried again and the security light did come on.
#1 son is coming down to redo his work today and my question is - what are the chances that the wiring harness the sensor is attached to is actually where the problem is? I don't even know what the thing is wired to - perhaps you can explain?
AnswerHi Carol,
The installation of a crank sensor should not have caused the battery to run down, which is what it sounds like has happened. Unless something else was left on while doing the job, like a glove box light or trunk light I don't see what would cause the draining of the battery.
On the crank sensor installation, it is important for him to press the tip of the sensor against the hidden surface that it is supposed to sense and while doing that tighten the retaining screw to hold it in the place. If it is not in close contact it will not work. He can test whether it is working with a voltmeter if he has one. Let me know and I'll tell you how. It is connected to the engine computer, three wires: one a signal wire, one a ground wire, and one an 8 volt supply wire. All there are low current wires so they would not drain the battery, and would be off when the ignition is off in any case.
The sensor comes with a paper spacer on its tip, and that is what actually comes in contact with the surface, and wears away leaving the tip at just the right distance to sense without being damaged by the spiining surface it 'looks' at. If the spacer is work away that you need to get a new spacer from a dealer to reinstall it correctly.
On the other possible causes you might try to get a fault code readout. Try using the ignition key to get fault codes:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapased time. Then watch the check engine light to see if it begins to flash, pause, flash, etc. If so, count the number of flashes before each pause. Repeat the process to be sure of getting an accurate set of flash counts. Tell me the results and we'll go from there.
I'm not clear as to what a catch or skip is: do you mean a loss of engine power, or something that is being driven by the engine seems to 'hang up'. If you have any more specific description that would help.
Roland
