Recently my Ram has begun making a "cracking" sound under heavy acceleration. It sounds like popcorn popping from inside the engine compartment. When I back off, you cannot hear it.

This happens, for example, when I gun it getting on the freeway. (or try to pass other vehicles)

It does not do it while sitting in my driveway and revving in park/neutral.

The truck does not leak/use up any fluids (besides gas of course!).

 

https://dodgeforum.com/forum/2nd-gen...um-thread.html

Check out that link.

The "cracking" sound you describe could be valve rattle, which is a side effect of, but not limited to a blown plenum. Has your's been replaced yet? If not that's a good place to start. A blown plenum can cause a wide array of problems.

 

I will have to check it out tomorrow.

I know when I bought the truck a year and a half ago, they had the intake manifold off.
(they let me "see" the truck and the work they were doing before I purchased it)

I would assume they would have replaced it then. *crosses fingers*

I will try to look down inside tomorrow!

 

Well there's always a chance they have replaced it already, and if they did it RIGHT then you shouldn't have any problems, but anything can happen.

If indeed the noise is valve rattle you could pull the valve cover's and take a look, see if anything is loose or clearly broke.

 

sure its not spark knock ur hearing?

 

I have never experienced spark knock first hand, if it is spark knock what could I do to resolve this?

 

Sounds like my truck was doing something similar. I changed the plugs, wires, ran some Seafoam trough it, and it's been fine ever since.

When it's popping, does it refuse to go higher than a certain RPM, because that's what mine did. what that RPM was, idk, because my truck doesn't have a Tach.

 

Spark knock, ping, or predetonation is a metallic type sound, like marbles rattling in a coffee can. The most common cause is a vac leak due to a blown plenum gasket. Best way to check for this particular problem is right after you shift into OD, let the RPMs drop just a bit, but don't let it fall back into 3rd, then depress the pedal moderately firm and try to accelerate. If it starts to rattle like marbles in a can, you can be pretty certain it's predetonation.

 

Alright guys. Well I think I may have finally gotten to problem fixed.

First I started off by checking the plenum. Did the magnet test and it's definitely steel, but there is NOTHING in the bottom at all.

So then I basically said screw it, and I went and bought new plugs (Autolite Copper), wires, distributor cap/rotor, and some Seafoam.

Ran the Seafoam first (and made sure it was all out), and then replaced all the other parts. Truck seems more responsive already (check out the cap in the pics below, this had to be the reason).

I will have to go out tomorrow and really test it.

New Plugs


Inside Cap


Outside Cap


Rotor


Old Plug


Carnage


Thanks for the help guys, i'll be sure to update tomorrow whether or not it fixed the MAIN issue.