Wont start, no spark from the spark plugs

Tiny
CHERYL SERVIC
  • MEMBER
  • 1998 PLYMOUTH BREEZE
  • 2.0L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 11,000 MILES
Our car wont start and we get no spark from the spark plugs. We replaced the fuel filter. And still no difference. We replaced the spark plugs. The only check engine light that is on is for an 02 sensor. But nothing else. It dose crank but wont start? What could be the problem?
Do you
have the same problem?
Yes
No
Thursday, November 10th, 2016 AT 4:25 PM

1 Reply

Tiny
CARADIODOC
  • EXPERT
You have no spark, so you replaced the fuel filter? First of all, be aware that on Chrysler products, except for diesel engines, you will never solve a running problem by replacing the fuel filter. They often last the life of the vehicle.

The second thing I must comment on so you are aware of it is diagnostic fault codes never ever say to replace a part or that one is bad. When a part is referenced in a fault code, as with your oxygen sensor code, that code only indicates the circuit or system that needs further diagnosis, or the unacceptable operating condition. There are dozens of codes related to the oxygen sensors, and they all mean very different things. A replacement sensor will solve the problem about half of the time. First you have to inspect the wiring and connector terminals, and look for mechanical problems related to the sensor.

When you are missing spark and fuel injector pulses, look for what both systems have in common. That is the crankshaft position sensor and the camshaft position sensor. The engine computer needs signals from both of those to know when the engine is rotating, (cranking or running). That is when it turns on the automatic shutdown (ASD) relay. That relay sends current to the ignition coils, injectors, alternator field, oxygen sensor heaters, and fuel pump or pump relay.

Often a fault code for a missing crankshaft position sensor signal or missing camshaft position sensor signal will not set simply from cranking the engine. You need a scanner to view live data. That will list each sensor, during cranking, with a "No" or "Present". Without a scanner, you can still see if the ASD relay is turning on. Measure the voltage on the dark green / orange wire at the ignition coil pack, any injector, or either small terminal on the back of the alternator. A test light works best for this because digital voltmeters don't respond fast enough. You should see twelve volts on that wire for one second when you turn the ignition switch on, then it will go to zero volts. What is important is if that twelve volts comes back during cranking. If it does, you have a spark problem OR a fuel problem. If it does not come back during cranking, you will have no spark and no fuel.
Was this
answer
helpful?
Yes
No
Thursday, November 10th, 2016 AT 6:11 PM

Please login or register to post a reply.

Recommended Guides