2003 Dodge Ram 3500 Cargo Van 5.9L 150,000+ miles

Would sputter and stop after acceerating from a stop. Would have trouble restarting. Then one morning would not start at all.

I just repleaced the distributor cap, rotor and sensor. Van inmmediatly started.

When smoothly accerating, engine would do great but if I accerated moderatly or more, the engine would sputter and nearly shut off. A smooth and gradual acceration is fine but any more either in park, neutral or on the road and the enging would sputter and nearly die. Have not tried highway driving for the obvious reasons.

Any suggestions guys? The plugs could be changed but everyone knows how fun that is on these vans. Could it be a vacuum advance or somethig like that? Could the fuel filter be the problem?

Thanks,
Charles

 

You have weak spark, replace the ignition coil.

 

I almost bought a new coil today. I'll try installing a new one tomororw.

How can I measure the quality of the spark from the coil?

Thanks for the quick help!
~Charles

 

Most auto parts stores can test it for you. The problem though is that sometimes a coil will only act up when hot and will test good when cool. In such a case the test is meaningless. I prefer to just look at the spark after the engine is hot. If it's a blue spark it's good, if it's orange or yellow it's weak.

During acceleration or any other engine load, the pressure (atmospheric density) inside the cylinders increases. This is when a weak spark becomes most apparent. It is because a weaker spark does not have the power to conduct across the additional molecules between the electrodes of the spark plug. A simplified example of this is to compare punching your fist into the palm of your other hand through the air and then again under water. The impact through the air is more powerful because air is less dense than water.

Of course it's possible something else is wrong, but based on what you've described the coil is the most likely culprit.

 

Indeed replace the coil. Alloro is correct.

As for changing the plugs, the passenger side of the van is rather easy with the dog-house off. The driver side is a bit more narrow allowing only good access to the back rear plugs. Getting to the front two plugs requires a universal and the driver front wheel taken off for an alternative access.

For plugs, the Autolite single platinum work very well. AP5224.

When replacing the ignition cap-n-rotor, make sure it's copper/brass contacts. The "cheap" aluminum contacts will only last a few months at best.

 

SOLUTION:
Replace the coil.

Worked great. Thanks Alloro! Engine runs great.

 

Yep, it was the coil. I didn't check to see if the cap-n-rotor were copper/brass. I'll get a set keep them ready for the future.

Thanks for the info on the plugs. I have a new set but have not changed them yet. I'll schedule that for next weekend. I need to get a universal first.

 

New problem! Test drove for about a hour, ran great. Sounded wonderful.
Today I'm idling for a while and the engine just shuts off. Started right away. Ran for about 10 minutes and did this again. Thought it might be something from the injector cleaner I put in the yesterday.

This happened about a total of 4 times and then wouldn't start at all. Started to check all the wires I touched yesterday. Couldn't see a part at the distributor so I checked at the coil. No spark on from the new coil.

Put all back together, crank it again. Still no joy. I’m looking at the engine when I hear the idiot light bong like I’m low on gas. But just filled the tank yesterday. Then I see it.

NoBus

Reinsert the key and try again. The odometer is flashing.

This is my first no bus error so I’m drilling down it now.

But here’s the bid question, what are the chances of a nobus error if the windshield has been leaking? Could it be related?

I recently realized that the windshield replacement of a few months ago was done poorly and water is getting into my dash. The undermat is soaked.

Thoughts? I’m already looking at the no bus posts.

 

Nobus error. Solution, replaced the PCM.

Van runs fantastic. Better than is has in years.

BTW, I bought an ODB-II interface device to read the diagnostic codes. I was unable to read any codes. This may be because a nobus error prevents the ODB-II from being read or because the PCM was just dead.

New PCM with updated software cost $387 and included a lifetime warranty upon core return.