Quite a few things can cause your 2000-2003 4.7L Dodge Durango or Dakota to not start.
This tutorial will cover 5 basic things that can cause a no start problem: a bad crankshaft position sensor, a defective fuel pump, no engine compression, and a blown head gasket.
Here are the contents of this article at a quick glance:
- Difference Between A No Start And A No Crank Condition.
- No Start Condition Basics.
- What Tools Do I Need?
- TEST 1: Testing For Spark And Fuel Injector Pulses.
- TEST 2: Testing The Fuel Pump's Pressure.
- TEST 3: Making Sure The Engine Has Good Compression.
- TEST 4: Checking For A Blown Head Gasket.
- No Start Troubleshooting Summary.
- Where To Buy An HEI Spark Tester And A Fuel Pressure Gauge.
- More 4.7L Dodge Tutorials.
Difference Between A No Start And A No Crank Condition
Before I jump into the tutorial, I want to explain the difference between a ‘does not crank’ problem and a ‘a no start’ problem.
When the engine cranks but does not start: Your Dodge Dakota or Durango's starter motor is cranking the engine but the engine is not starting.
When the engine does not crank: Your Dodge Dakota or Durango's engine does not turn over when you turn the key to crank and start the engine. This is usually due to a bad starter motor, bad ignition switch, bad neutral safety switch, or the engine is locked up.
If the engine in your Dodge Dakota or Durango's does not crank, you should test the starter motor. The following tutorial will help you test the starter motor: How To Test The Starter Motor On the Car (Step by Step).
No Start Condition Basics
What will usually cause a no start problem is one of three things: a no spark condition, or a no fuel condition, or an engine compression problem.
This boils down to doing 3 basic tests to get to the bottom of the no start problem. We need to:
Test the ignition system: We need to make sure that each cylinder is getting spark. This is accomplished by making sure that the ignition coils are sparking.
A no spark condition, that's causing the engine not to start, is usually caused by a defective crankshaft position sensor.
Test the fuel system: We need to make sure gasoline is reaching the cylinders. This is accomplished by doing a a fuel pump pressure test.
A no fuel condition, that's causing the engine not to start, is usually caused by a defective fuel pump.
Test the engine compression: We need to make sure that each cylinder has a normal compression value.
An engine compression problem, that's causing the engine not to start, is usually caused by a serious internal engine problem (like a thrown rod or busted timing chain).
Test for a blown head gasket: A blown head gasket is usually the result of severe engine overheating and can cause the engine to crank but not start.
In the following pages you'll find a basic testing guide so that you can find out what's behind your 4.7L Dodge Dakota or Durango's no start problem.
What Tools Do I Need?
To find out what's behind your 4.7L Dodge Dakota or Durango's not start problem, you're gonna' need a few specialized tools.
Here's a basic list of what you'll need:
- Spark tester.
- Noid light set.
- Fuel pressure tester.
- Engine compression tester.
I'm gonna' suggest that the spark tester that you use be an HEI Spark Tester. This tester is the most accurate tester on the market and isn't expensive. You can find out more about it (and where to buy it) here: HEI Spark Tester. Or you can take a look at this section: Where To Buy An HEI Spark Tester And A Fuel Pressure Gauge.
You'll notice that I didn't include a scan tool in the list. But if you have one, I can tell you that it'll come in very handy. Why? Because some of the components that cause a no start condition can leave a specific trouble code (when they fail).
In this tutorial I haven't included it (a scan tool) in any of the suggested tests because they can be done without one.
As you can see, none of these tools will break the bank. Most of these you can borrow from your local auto parts store (after leaving a small deposit).
Let's turn the page and get testing...