So a while back my 95 Grand Voyager started making this odd popping noise while accelerating, and momentary losses of power would occur during the pop. It started off occasional at first, but has gotten worse over time. Seems to be worse when climbing grades. The popping is not rhythmical, and only does it while accelerating not idling. Sometimes the van will run great for a 10-20 minute span, then I'll try to take off from a light and it just sputters and pops as I'm trying to get up to speed. Once I'm up to speed, it'll be fine. May or may not do it at the next light.

The popping noise sounds like a miniature backfire, something hitting something else in the engine or transmission, like it's gargling a rock, or like gear teeth are hitting each other or something.

Shortly after this started happening, I got the "check engine" light coming on if I was on the freeway for more than about 20 minutes. The first couple of times that happened, I would pull off to the side and check all my fluids do a visual inspection. Everything would look fine, and I'd start it back up, and the light would be gone.

I have changed spark plugs, air filter, side fuel filter, topped off transmission fluid, and most recently swapped out the EGR valve. A computer scan brought up no codes, and read the fuel system as being fine.

Changing the EGR valve has stopped the "Check engine" light from coming on, but the random and increasing popping and sputtering is still there. When I changed it, there was some fluid of some sort where it bolts onto the block. Looked a chocolate milkshake.

Engine is a 3.3L, 173K on it. I don't think anything major has ever been done to it.

Any ideas?

 

Did you replace the spark plug wire set? And are you loosing coolant?

 

I had the same issue in one of my trucks a while back, although i got an o2 sensor code. Have you checked to see if the cat is clogged?

 

I may have replaced the spark plug wires when I bought the van 5 years ago. Other than physical damage, how can they go bad? Could I just check them for continuity and/or physical damage? I have not noticed a coolant problem, but I'll check it when I get off work.

How I check the cat? Or is that not a thing for a novice?

Thanks for the responses!