Q: Spark Plugs spark once

asked by on

My car suddenly didn't start. It’s been working great and now it won’t start. I've checked the injectors, fuel relay, fuel pump OVP relay, and they are good. The spark plug wires, distributor are new, and I checked the coil and EZL and CPS and they are all good on ohms. The thing that is puzzling is that my spark plugs only spark once. They have a nice bright blue spark, but the cylinders spark only once. One other thing I noticed was that my rpm needle goes up and down between 500 rpm – 1500 rpm when I crank the engine. This happens even though the engine spins at the same rpm. Do you think I have a bad CPS?

Either a failing crankshaft sensor or impulse wheel could be the cause of the fluctuating RPM reading. The crankshaft sensor signal is often used to start both fuel pump operation and start the ignition coils with the camshaft sensor setting the sequential injection and ignition firing order.

You may want to have faults read out of the ECM prior to replacing the crankshaft sensor and look at the crankshaft sensor wheel. If the sensor is mounted on the front of the engine the sensor wheel may be part of the dampener and may have slipped or vibrates. If it is a sensor wheel that is part of the flywheel, a bent tooth may be the cause. To have this resolved, you may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the equipment and expertise to correct this hard starting issue.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Spark Plugs spark once

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Q: Starting issues

Hello and thanks for writing in. Depending on what the vehicle does when trying to start it may help to narrow this down. If it produces a click sound, this may be related to a faulty starter solenoid. If it...

Q: Car dies after going 5 to 20 miles. If it sets for 2 to 24 hours it starts again and goes 5 to 20 miles.

Hi there. The issue is with the ignition switch. The switch has a faulty tumbler and disconnects the wiring in the steering column. The best thing to do is replace the ignition switch and check the wiring in the steering...

Q: Repair costs and worth? Resell?

Spark plugs on your vehicle should be replaced every 30,000 miles, if they are of the non-platinum type and every 60,000 miles if they are platinum plugs. To obtain service on the spark plugs, please request spark plug replacement. Oxygen...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...