QuestionQUESTION: Recently had new brakes and oil change on 2000 Dodge Caravan. The Mechanic said the spark plugs needed to be changed. My son did that yesterday but could only reach three in front. Could not reach the back. My daughter drove it home and now it wont start. They key turns over no clicking noise so dont think it is the battery. It just isnt fireing. Has a full tank of gas 93000 miles on it. My son is not a mechanic but seemed to know how to change out the plugs he could reach. What due you think the problem is.??
ANSWER: Hi Sandra,
If the problem is that the starter motor is not even turning over the engine ('no clicking noise') then that is the first issue. Open the hood and find the rectangular box near the battery and open it. There is a row of relays on the driver side of the box. The fifth one counting from the rear is the starter motor relay. Have your daughter try the key to the 'start' position while you listen/touch that relay to determine whether it is clicking. If so, then the power should be reaching the starter motor so probably the battery is too weak (a light left on overnight perhaps) or the starter or its internal switch itself may be weak. If the relay doesn't click then the gearshift lever may be slightly off center in the park position. Try moving it a bit and try again, and if that doesn't work try putting it in neutral for a start. If nothing causes the relay to click then also take a look at fuse 23 in that box to be sure it isn't blown and then look at fuse 10 in the fuse box under the dash on the driver side. Those are all the items that could cause a no starter motor situation.
Roland
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QUESTION: Hi Roland, Thank you for such a timely answer the motor wants to start but cant. I meant that we did not think the battery was bad because then we would just get that little clicking noise and that is not happening. It dose turn over. My son checked the plugs and changed them back to the original. He then went to the fuse panel under hood on drivers side and found a fuse that was burned "Engine" 20 amp 3rd from the right (no #). He change that out and tried to start the car again, it immediately burnt out the fuse again did that several times. It still turns over but wont start.
AnswerHi Sandra,
Do you mean the second fuse (of 18 fuses/sockets) counting from the rear of the box?
That is what I have seen called the 'engine' 20 amp fuse. If that is the fuse then I suspect that what may have happened is that one of the several different devices that draw current from that fuse has shorted the current to ground which overdraws the fuse and burns it out.
The most likely object is called a 'heated oxygen sensor' and it may be the one that is on the back side of the engine where brother tried perhaps to change the spark plugs unsuccessfully and in so doing broke one or more of the four wires on the sensor. It looks like a spark plug but is mounted on the exhaust manifold. The wire between the tip of the sensor and the plug to which it attaches are rather flimsy.
So ask brother if when reaching behind the engine to get to the plugs that might have happened; have him try to find it and check the condition of the wires. If they are found to be broken then unplug the plug for the sensor and that will stop the short condition. Then the engine should start. But the sensor should be replaced for the engine to run well again. You put penetrating oil on the threads if it and let it sit overnight before trying to remove it. You install it like a spark plug but be very careful not to damage the wires. Tighten it about the same torque as a spark plug.
There are other possibilities for a short to occur that would blow fuse #17 if that doesn't appear to be what happened. But this is the most plausible. Let me know.
Roland
