Chrysler Repair: Tachometer doesnt work: Stratus, camshaft sensor, crankshaft sensor

Question
QUESTION: Ronald,

I have a 1996 Dodge Stratus ES 2.5L (v6), in which the Tachnometer doesn't come on/work. I took the car to a Mechanic about the problem and he told me that i need to check the Tach lead, which he himself didn't know where it exactly was. He just said it was somewhere in the wiring and it would probablly cost alot. We also think that it's the same problem why my cruise control doesn't work. Any information about the location of the Tach lead or any other solutions will be appreicated. Thank you

         from,
         Greg

ANSWER: Hi Greg,
There is no separate tach lead. All the data for the dash comes in on the same pair of wires so it either all works or none works. The signal is generated by the engine rotation sensors that are needed for the ignition system so that if that system works it means the problem is in the cluster. You can check for digital fault codes 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 begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat the procedure to be sure of a reproducible set of counts. The last pair of counts will always be 5 each which means 'end of code readout'. Tell me the counts in the order appearance if there are any and we'll go from there. The cruise control may be 'out' due to a broken wire between the steering wheel and the steering column called the clockspring.
Roland

---------- FOLLOW-UP ----------

QUESTION: Roland,

The code read 12-55, 3 times...My car also stalls at red lights and start to lose power while i'm idling, but then straights out when i push the pedal down futher...is these problems due to the tachometer not working?...Someone told me it could be a camshaft sensor or the crankshaft sensor...What color is the wire from the distributor to the instrument cluster and why can't we find the pig-tail plug?...Does some models have it or does all models have it? cause we can't find it on mine

Answer
Hi Greg,
As I explained, there is no single wire for the tach; the tach signal is digitized and if the engine runs reasonable then there is nothing wrong with the signal that also drives the tack, the same signal goes to the cluster on the data bus wire pair which is working or you would get no data at all on the dash. The problem has to be the tachometer head itself or the printed circuit board.
On the fault code readout, nothing there is remarkable so I don't think this has anything to do with the sensors you mention.  
I would check the egr valve to see if it is sticking slightly ajar which will cause the rough idle/dieing. Here is how I have told others to deal with that:
The first thing I would do is check the mechanical function of the egr valve which is located along a pipe that runs from the left exhaust manifold (on the side of the engine facing the front of the car) to the intake manifold area (where the incoming air in the large rubber tube enters the throttle). That valve is metal and has a round fitting with a vacuum hose attached, mounted on the top of the valve, and the round part is attached to the main body of the valve by a sort of saddle.  Inside the open saddle you will see a metal rod (with a slot) that connects the round top fitting to to the valve body. That rod is a stem on the valve and it is supposed to go in and out in response to the engine vacuum which varies with RPM and throttle opening (gas pedal position). Take a spray can of WD-40 or other penetrating lubricant and spray the stem where it enters the valve body and then use a regular screwdriver blade tip inserted in the slot to lever the valve in and out to try and free up its motion. Also check all the rubber vacuum hoses associated with the valve and a nearby vacuum solenoid valve. If the valve seems to open (against the action of a spring) and close firmly by the spring action when using the screwdriver blade to facilitate the motion, then you should be able to now start the engine. You can, once it is idling, check that the valve stem moves when you rev the engine from idle to 2500 rpm and back to idle. If it still won't start, then removing and cleaning the interior of the valve, or buying a new one if it seems too crudy and corroded inside, is the next step to getting the engine to start/idle.
Good luck!
Roland