QuestionQUESTION: Have a 1995 plymouth grand voyaged v6 3.3 liter that wont start.
Problems started when the van stalled twice within a couple of weeks.
Replaced the fuel filter and it ran fine for a short time then would not
start at all. It sounds like everything is working but no spark. Fuel pump
comes on, starter engages, tried spraying ether in air filter and still no
start.
Replaced crank position sensor, checked fuses, no start. Replaced coil
with known good coil and we are gettig no arc or spark. Opened up ECM
casing and its hard to tell for sure because of the gel but don't see any
scorching. Not sure what to try next any suggestions would be much
appreciated.
ANSWER: Hi Stephen,
I wonder if it might be the cam sensor for if that is bad there will be no spark (and similarly for the crank but you already changed that.
Fortunately you can find out by doing a fault code readout using the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains 'on', to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the process to be sure of an accurate/repeatable set of flash counts. Then group the counts in pairs in the order of appearance to form the 2-digit fault code numbers. The last code number is always 55 which means 'end of readout'. The code for the cam sensor is 54, while the code for crank sensor is 11. Tell me the numbers and we'll go from there.
The codes will be current from the most recent time that you disconnected the battery. If you disconnect the battery all the codes are erased except a new 12 code, which means battery disconnected recently, is set. You would want to try starting it a few times after disconnecting the battery so that any new codes it can detect will be logged.
Roland
---------- FOLLOW-UP ----------
QUESTION: Roland,
Thank you for your response and sharing your knowledge. I did as you
said and I am not quite sure about the results. There were 2 possible
sequences. 1 blink 2 blinks 1 blink 1 blink then of course 5 and 5. The
second possibility is 1, 2, 2, 5, 5 ( which doesnt make sense to me since
they shoul be in pairs) I had a difficult time telling if the third number was
a 2 or two 1s. Thank you again.
AnswerHi Stephen,
It appears that you have 12,11,55. So if the battery was disconnected AFTER you replaced the crank sensor then that would be a 'fresh' crank sensor fault code. That could mean either that the sensor you put in didn't get pushed in fully until the paper spacer tip of the sensor touched the surface of the flex plate and then held in that position while you tightened down the retaining screw, or the sensor wiring is faulty, or the sensor was faulty.
The wiring would be 9V on the orange wire when the ignition switch is in the run position coming from pin 7 of the pcm; then the black/light blue is the signal ground wire and the gray/violet is the signal wire. Those go respectively to pins 4 and 24 of the powertrain controller. If you probe through the insulation with fine pins you should see the crank signal between the latter wires as an oscillation between 5v and 0.3v as you rotate the engine by hand using a ratchet on the crank pulley bolt and with the ignition in the 'run' position. If that were present and 'seen' at the pins of the pcm then you should get spark unless there is something wrong with pcm. If you don't get that, then try resetting the sensor so that it's tip is pressed against the hidden surface of the flex plate.
Roland
PS Please 'rate' my answer. Thanks
