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Hi.. my girlfriend has a 1990 dodge dynasty. she just bought it and got it from an older couple. The timing belt was broke.. We replaced the distributor cap, plugs and rotor button. when we go to start the car it cranks over really good but it wont start. we just replaced the plugs plug wires, computer,. we checked the compression of the cylinders and they are reading around 120. The head gasket is good. do you have any idea of what the problem could be?. we replaced the fuel filter and stuff. This car is just puzzling everyone that is working on it. it doesnt have a crank angler sensor on it. so i really need some help.
thanks chris
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Hi Chris,
Which engine do you have in it? There is not a crank angle sensor but rather a sensor in the distributor that is for timing the spark and, if multi-point injectors, for firing one or the other bank of injectors. So let me know which. I think the fact that you have compression is good. And if you are sure that you set up the timing mark on the distributor drive sprocket correctly then the spark should be somewhere near right. Have you pulled the center wire from the distributor cap and held it 1/4" from the head, then crank for 5 seconds to see if you are actually getting a spark? Let me know that answer. If you don't have spark then either the coil is bad or the sensor in the dirstributor is bad. I can tell you how to check that out too.
One quick thing to do is check the engine controller for the presence of any fault codes that would be diagnostic of the problem. Just turn the ignition switch: "on-off-on-off-on" and leave "on", doing this in an elapsed time period of less than 5 seconds. Then watch the check engine light to begin to flash, pause, flash, pause, etc. There can be anywhere from 1 to 9 flashes before a pause. Count the number of flashes before each pause and note them down. Repeat the readout until you are sure you get the same set of flash numbers two times in a row. The last two sets of flashes when you do the readout are always 5 in each. Then you pair off the numbers in the order they came out to form two-digit numbers. These are the fault codes. The last number will always be 55 which is the code for 'end of readout'.
You can either go to www.allpar.com/fix/codes.html and look up what the other numbers mean or write me back with the numbers. So see about spark and about codes. Also, do you hear the fuel pump run for about 2 seconds when you first to the ignition switch to run? It is in the fuel tank. If you have neither spark and you don't hear the fuel pump run then there is no voltage going to the spark coil and fuel pump presmably because the autoshutdown relay is failing to close. That could be due to the sensor in the distributor being bad or a faulty relay. The code for no signal from the distributor is 11.
Anyhow those are some possibilities, why don't you check them out and let me know answers all of my questions.
Roland
The motor is a 3.0 v6. I ahve checked the spark and it does have it.
Answer -
Hi Chris,
That is good to know and also good that you have spark. I trust that the spark lasts for a full 5 seconds of cranking; if not checked yet, check that out. I would then suggest a couple of things:
Make sure that the spark plug wires are arranged clockwise around the cap, starting with the position that is toward the rear of the car: 1-2-6-4-5-3 There are internal rearrangements in the cap that can fake you out because the firing order of the engine is 1-2-3-4-5-6, and the rotor actually rotates counter-clockwise.
Then I would check with a timing light with the engine being cranked that with the sensor on the #1 wire that you have the timing somewhere between 0 and 16 BTDC.
And then I would check the trouble codes as I described.
And then I would check to see that a plug is wet from getting fuel to the cylinder.
And then write back with the results.
There are a number of other things to check next if the engine hasn't started yet!
Roland
Roland.. Really sorry to waste your time but i finaly figure out what the problem was. The car has a broken fly wheel. MY girlfriends aunt took the starter off and went to replace it and thats when she found that the flywheel was broke.. thanks fr everything though.
Chris
AnswerHi Chris,
Thanks for the reply. I am curious though as to why the flywheel would cause the engine to not start? You said that it turned over and that you can get compression. I thought the flywheel (or flex plate if it is an automatic transmssion) only relates to the starter motor's ability to mesh with the crankshaft to turnover the engine, which yours seems to be doing. If you have an explanation I would be interested in knowing.
Roland
