Tip & How-To about Chevrolet 1500

Engine will not start

Either you are not getting spark or not getting fuel. A bad crankshaft position sensor would cause no spark at all. You can pull one spark plug, place it back on the plug wire. Lay the plug electrode next to a metal surface. Have someone else crank over the engine while you observe for spark. You should see a spark jump from plug to the metal surface. (plug electrode should be no more than 1/4" away) If you don't have spark, put the plug back in and move on to the next plug and try that one. (the correct way is to use a spark tester) If you have no spark in any plug, you may want to test the crankshaft position sensor with an ohmmeter. You can also use a meter to test power at the ignition module.
If you find that you do have spark in every plug, then it's possible that you don't have fuel. There is a fuel pressure test port on the fuel rail. There is a cap and a valve. With the key in ON position ,you can place rag over the test port, press in on the valve and there should be fuel that comes out meaning there is fuel pressure. (the correct way is to use a fuel pressure gauge if you have one)
If you find there is no fuel pressure, turn the key off and back on again. You should hear the fuel pump. If you can hear the fuel pump, then it is working. That means you may have a plugged fuel filter or faulty fuel pressure regulator. If you do not have hear the fuel pump, check the fuse and fuel pump relay. You can test the relay and a fuse with an ohmmeter on the ohm setting. You can also use a voltmeter and check power to the relay and also to the fuel pump to test for 12 volts. If you have power to the pump but the pump is not running, it is likely faulty. If you don't have power to the pump, then either the relay or fuse is bad. If they test out ok, then test power from ECM.

These are the most common causes of a no start. If you have any bad sensors of any sort, it would likely set of the check engine light. Then the computer should be tested for engine codes which can be done with a scan-tool.

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97 oldsmobile achieva wont fire changed coil pack spark plugs cam sensor still wont start


Make sure battery has a full charge and battery connections all good.
If it cranks good but won't start, have a helper crank it while you visually check for spark at the spark plugs. If spark everywhere, use a gage and check proper fuel pressure and fuel injector pulse.
If you having a problem with more than one system, I want to check for rpm signal, that usually comes from the crank sensor. Not sure why you replaced cam sensor? I always want to check sensor wiring circuits before replacing anything. Don't replace anything unless your testing points in that direction.

Nov 04, 2016 | Oldsmobile Cars & Trucks

1 Answer

will a bad crankshaft position sensor cause the fuel pump not to get power to it ?


Crank sensor is for spark, cam is for fuel timing. Fuel pump is bad fuse/relay or pump. Year make and model?

Feb 15, 2015 | Cars & Trucks

2 Answers

98 Pontiac GRAND am


The plugs and crank sensor could have done it, but the TPS and idle air control would have nothing to do with a random miss.
A more likely cause is the ignition module or a fuel problem. You may have to wait until the problem is bad enough to kill the engine or you have more codes to check out.

May 20, 2013 | Cars & Trucks

1 Answer

1998 elantra was running fine and motor just died. Will turn over fine but will not start. I had filled up with fuel and driven about 50 miles when this happened.


Is the engine getting fuel and spark?

Try to put a few teaspoons of gas in the throttle body to see if it starts up. If it doesn't then the engine's spark plugs may not getting spark.

A possible coil may be the root of the above problem.

If it does start and run for a few seconds then the spark is good, but the fuel pump may not be pressurizing (bad fuel pump) or the fuel injectors are not firing (possible PCM or Powertrain Control Module).

A crankshaft position sensor can also cause a no start condition.
It is located near the Crankshaft of the engine.

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Here's more information about the crankshaft position sensor which if bad, can cause a no start or no run condition.
Crankshaft Position Sensor Engine speed is a very important input to the Engine Management System (EMS). Crankshaft speed and position are the basis for many calculations made by the computer. Crankshaft position values are transmitted to the computer by pickup coils also known as Permanent Magnet (P/M) generators, hall-effect sensors or optical sensors. The Crankshaft Position Sensor (CKP) also known as engine speed sensor is located in close proximity to the crankshaft.
In addition, the EMS uses minute variations in the CKP sensor data to determine engine misfire. The EMS uses this information in conjunction with the camshaft position sensor to perform misfire diagnostics.
Related Symptoms No Start / Intermittent Start Condition – Can be caused by a faulty crankshaft position sensor due to loose connections, bad grounds, high resistance in the circuit, or opens in the circuit. (See also Engine Mechanical)
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These are just a few possibilities, and if one takes it to the dealer to have the engine diagnosed, that might be a good place to continue of the above doesn't isolate the problem sufficiently for repair of the no start condition.

Aug 06, 2010 | 1998 Hyundai Elantra

2 Answers

1994 Chevrolet Astro It takes 2 to 5 cranks to start. Each crank turns the cars electrical stuff on and revs the engine however it doesnt start.What is the issue?


Either you are not getting spark or not getting fuel. A bad crankshaft position sensor would cause no spark at all. You can pull one spark plug, place it back on the plug wire. Lay the plug electrode next to a metal surface. Have someone else crank over the engine while you observe for spark. You should see a spark jump from plug to the metal surface. (plug electrode should be no more than 1/4" away) If you don't have spark, put the plug back in and move on to the next plug and try that one. (the correct way is to use a spark tester) If you have no spark in any plug, you may want to test the crankshaft position sensor with an ohmmeter. You can also use a meter to test power at the ignition module.
If you find that you do have spark in every plug, then it's possible that you don't have fuel. There is a fuel pressure test port on the fuel rail. There is a cap and a valve. With the key in ON position ,you can place rag over the test port, press in on the valve and there should be fuel that comes out meaning there is fuel pressure. (the correct way is to use a fuel pressure gauge if you have one)
If you find there is no fuel pressure, turn the key off and back on again. You should hear the fuel pump. If you can hear the fuel pump, then it is working. That means you may have a plugged fuel filter or faulty fuel pressure regulator. If you do not have hear the fuel pump, check the fuse and fuel pump relay. You can test the relay and a fuse with an ohmmeter on the ohm setting. You can also use a voltmeter and check power to the relay and also to the fuel pump to test for 12 volts. If you have power to the pump but the pump is not running, it is likely faulty. If you don't have power to the pump, then either the relay or fuse is bad. If they test out ok, then test power from ECM.

These are the most common causes of a no start. If you have any bad sensors of any sort, it would likely set of the check engine light. Then the computer should be tested for engine codes which can be done with a scan-tool.

Jun 18, 2010 | 1994 Chevrolet Astro

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