A cranks but does not start condition, on your 3.0L V6 Honda Accord or Odyssey, can have you pulling your hair out since one component out of a bunch can fail and be the cause of the problem, for example you could have a:
- Broken timing belt.
- Bad fuel pump.
- Bad ignition coil.
The list goes on, but you get the idea. In this tutorial, I'll go into the basics you need to know to successfully diagnose a cranks but does not start condition.
Contents of this tutorial:
You can find this tutorial in Spanish here: Cómo Probar Un Arranca Pero No Prende (3.0L Honda Accord y Odyssey) (at: autotecnico-online.com).
APPLIES TO: This tutorial applies to the following vehicles:
- 3.0L V6 Honda Accord: 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007.
- 3.0L V6 Acura CL: 1997, 1998, 1999.
Difference Between A No Start And A No Crank Condition
Before we jump right into the basics of what causes a no-start condition, I want to clarify the difference between a no-crank and a no-start since they're not the same thing and knowing the difference will speed up your diagnostic.
Here's a brief description that'll help you make sense of this tutorial (and will help you find even more info online):
Cranks But Does Not Start Condition: This condition is also known as a no-start and it means that your Honda's starter motor is cranking the engine but the engine is not starting. This is usually due to a fault in the ignition system, or in the fuel system, or there's an engine mechanical problem (like a thrown rod, etc.).
Does Not Crank Condition: This condition is also known as a no-crank and it means that the engine is not cranking when you turn the key to crank the engine. In other words, the engine doesn't turn over at all. This is usually due to a bad starter motor, bad ignition switch, bad neutral safety switch, or the engine is locked up.
If your Honda doesn't crank and you suspect the starter motor, here's a tutorial that'll help you test it: How To Test The Starter Motor (Honda 3.0L).
No Start Condition Basics
Knowing the three things the engine needs to start is the key to successfully diagnosing the no-start condition your Honda is experiencing. These three things are:
- Air.
- Fuel.
- Spark.
This means that if our Honda doesn't start, then we need to focus on finding out what's missing. Usually either spark will be missing, or fuel will be missing, or the engine doesn't have compression (think broken timing belt). It's as simple as this! I know, I know, I may be over-simplifying it all but knowing that only one of three things is missing really helps to put the problem into perspective!
To get down into the nitty-gritty details- this means that troubleshooting the problem requires that you or I check for spark (with a spark tester), check fuel pressure, and if necessary, check the engine's health with a compression test.
I'll go into more specific details in the following headings:
1.) Ignition System
- The ignition system is the one tasked with creating and delivering spark to each of the 6 cylinders. Without spark, the engine will crank but not start.
- The ignition system of the Honda vehicles covered by this article use either distributor type system or a COP (Coil-On-Plug) ignition coil system. In a COP ignition coil system, each cylinder has its own ignition coil; thus eliminating the distributor entirely.
- In my experience, the most common component failures, of the ignition system that cause a no-start no-spark condition are:
- Ignition control module (ICM) -most commonly known as the igniter (if distributor equipped).
- Ignition coil.
- Distributor cap (if distributor equipped).
- Distributor rotor (if distributor equipped).
- All of the above ignition system components can be tested in a methodical way to find out exactly what has failed (if indeed something has).
2.) Fuel System
- The fuel system is the one responsible with supplying the engine with fuel.
- The fuel system component that causes the majority of no-start no-fuel problems:
- Fuel pump relay.
- Fuel pump.
- The fuel pump can be tested to make sure it has really fried using a fuel pressure gauge.
3.) Engine Mechanical System
- The components that are responsible for drawing in the air the engine needs are the: engine pistons, cylinder head valves, and all the other related components like: timing chain, etc.
- Although rare, internal engine mechanical problems can and do cause no-start conditions.
- Possible internal/external engine problems are:
- Blown head gasket.
- Blown engine.
- Busted timing belt.
OK, the list of possible things that can go wrong looks pretty long but it is rare to see (or have) two different components go bad from two separate systems at the same time.
The cool thing is, is that there is a diagnostic strategy that you can use to figure out exactly what's wrong with your particular no-start problem. Let's find out more about it in the next subheading.
No Start 1: Checking For Spark
The very first thing I'm going to recommend you do, to find the cause of your Honda's cranks but does not start condition, is to test for spark first. Why? Because it's been my experience that the majority of no-start conditions I've diagnosed and repaired had their root cause in the ignition system.
Specifically, the ignition system was not creating and feeding spark to all 6 cylinders. How can you find out? By testing for spark with a dedicated spark tester.
This suggestion, of testing for spark first, applies whether your Honda has a distributor-type ignition system or the more modern COP ignition coil system (in the Coil-On-Plug (COP) ignition coil system, you don't have a distributor anymore but 6 individual ignition coils sitting right on top of the spark plug).
Let me give the links to the tutorials you'll need to check for spark before I continue:
Distributor ignition system:
COP ignition coil system:
- How To Test The Coil-On-Plug Ignition Coil (2000-2003 3.0L V6 Honda Accord).
- How To Test The Ignition Coils (2003-2007 3.0L V6 Honda Accord).
If the ignition system is the cause of the no-start, you're not gonna' see spark at any of the 6 spark plug wires or 6 COP ignition coils. If there is spark being fed to all cylinders, then you can eliminate the ignition system as the cause of the no-start condition and can move on to other tests (like testing fuel pressure).
Remember, the idea behind checking for spark is to see if all of the engine cylinders are getting spark. Here are the most common causes of a no-spark result:
CASE 1: Spark was present in all cylinders. This result tells you three very important things: 1.) the crank sensor is functioning correctly, 2.) the ignition control module (also known as the igniter or power transistor) is OK -this applies to distributor-type systems, and 3.) the ignition coil is good. You don't have to spend any time testing them or any money replacing them.
Your next step is to verify fuel pressure. Go to: No Start 2: Checking For Fuel.
CASE 2: Spark was NOT present in all of the cylinders (DISTRIBUTOR TYPE). This test result tells you without a doubt that the no-start condition of your Honda is due to a malfunction in the ignition system.
CASE 3: Spark was NOT present in all of the cylinders (COP IGNITION COIL TYPE) This test result tells you without a doubt that the no-start condition of your Honda is due to a malfunction in the ignition system.
It's almost impossible for all 6 COP ignition coils to fail at the exact same time. So the most likely cause for this no spark condition is a bad camshaft (CMP) or crankshaft position (CKP) sensor.
No Start 2: Checking For Fuel
Checking that the fuel pump is delivering fuel to the fuel injectors is not that hard on your Honda (since you're able to tap into the rubber fuel pressure hose that connects to the fuel injector rail with a fuel pressure gauge and its appropriate adapter).
A bad fuel pump will cause your Honda to crank but not start since the fuel pump is the one responsible for supplying fuel to the fuel injectors.
The absolute best way to test the fuel pump is with a fuel pressure gauge. Any other method is not as accurate.
Still, the other method that I've used to test for a lack of fuel, is to spray starting fluid into the throttle body and I have a helper crank the engine. If the engine starts, then I now know that I need to take a closer look at the fuel pump to see if it's fried or not.
When testing the fuel pump (with a fuel pressure gauge), you'll usually see one of two results:
CASE 1: Fuel pressure is at specification. Not only does this result tell you that the fuel pump is OK but that the following components, that supply the fuel pump with power, are OK too:
- Fuel pump fuse.
- Fuel pump relay.
And so, there's no need to spend time testing them or money replacing them.
CASE 2: Fuel pressure is not present. This usually means that the fuel pump has failed, but not always. I would recommend testing/checking the following before condemning the fuel pump:
- After verifying that no fuel pressure exists, check that the fuel pump is getting power by tapping into the power circuit that feeds the pump with 12 Volts with a multimeter.
- Once you're tapped in, have a helper crank the engine while you observe your multimeter in Volts DC mode. If voltage is present (12 Volts), then you have confirmed that the fuel pump fuse and fuel pump relay are working perfectly.
- Confirming power to the fuel pump (with a multimeter) also verifies that the fuel pump has failed and needs to be replaced.
- If no voltage is present, as your helper cranks the engine, then the cause of no-fuel condition is due to either a bad fuse, fuel pump relay (known as the Main Relay).
No Start 3: Checking Engine Mechanical Condition
The biggest engine mechanical cause of a cranks but does not start condition on your 3.0L Honda Accord is a broken timing belt. The other is a blown head gasket or a blown engine. All of these conditions can be diagnosed by doing an engine compression test.
Here are some specific tips:
- When performing an engine compression test, what you're looking for is an average compression reading of NO LESS THAN 120 PSI across all or the majority of the engine cylinders (although 120 PSI is a pretty low compression value, the engine will still start and run although it'll idle very rough).
- If you have one or just two readings that are under 90 PSI your Honda vehicle will still start and run, albeit with a misfire condition.
- The following tutorial will help you do a compression test:
- You'll also need to check the condition of the timing belt and make sure you don't have a blown head gasket on your hands: How To Test For A Broken Timing Belt (1998-2007 3.0L V6 Honda Accord).
No Start Summary
By this point, in this tutorial, you now know that the cranks but does not start condition of your 3.0L equipped Honda is due to a lack of one of the following:
- Spark.
- Fuel.
- Air (from a lack of cylinder compression).
Also, you've found out that you can verify if these things are missing or not. To be more specific, you can: test for spark you can test the fuel pump (fuel pressure), and you can test the engine compression.
Thankfully, all of these things can be tested with simple tools. And this leads me to the next talking point.
To check the basics, you need tools. There's just no way around it. One of the analogies that I've always enjoyed repeating, about doing a job without the right tools is like trying to eat a bowl of soup with a fork.
So besides knowing what to test, you need tools to do those tests. You don't have to spend an arm and a leg, since you can buy a lot of diagnostics tools that are tailored for the pocket-books of the serious do-it-yourself-er. Here are some of the basic tools you'll need:
- Fuel pressure gauge.
- Spark tester.
- Compression gauge.
- Multimeter.
Most of these tools you can buy or rent for free (after you leave a cash deposit which you'll get back when you return the tool) at your local auto parts store (mainly AutoZone and O'Reilly Auto Parts). Or, if you want to save some bucks, you can buy them online.
Related Test Articles
You can find a complete list of articles here: Honda 3.0L Index Of Articles. Below, is a sample of articles you'll find in this index of articles:
- How To Test The Starter Motor (Honda 3.0L).
- How To Test Engine Compression (Honda 3.0L).
- How To Test The Coil-On-Plug Ignition Coil (2000-2003 3.0L V6 Honda Accord).
- The Basics Of Crank And Cam Sensors And How To Test Them (at: easyautodiagnostics.com).
If this info saved the day, buy me a beer!
