I just changed my spark plugs, wires, cap and rotor on my 99 Dakota 5.9. Two of the spark plugs broke off inside because of rust, but I got them out using pb blaster and an extractor bit. No pieces of the spark plugs fell inside the engine. When I started it up it had a knocking sounds. When I would give it gas it sounded like gunshots coming out of the exhaust. Could I have a bad rod or is it running rough because of the pb blaster burning out? I noticed a small knocking noise before the change, so I guess that cancels out the pb blaster theory. It was not as loud though


Videos with sound of it the best I could take:

 

I don't think PB blaster is the problem something got into a cylinder or two.

Compression test next back to pulling plugs

 

thanks maybe some broken rust got into it. I'll do a compression test and then pull plugs one by one to see if it stops. Does anyone know how much it cost to replace rods?

 

Just a thought but are you sure you got the coil wires back on properly? If you got the firing order out of whack it could be a misfire.

 

I had a feeling you would have this problem


A test by hand for any binding would have reveled a possible problem


How pull all the plugs and try to hand crank the engine I know not as easy as it sounds a V8.

 

I am pretty sure I got the firing order right.

 

My guess you caved in a piston and or damaged a rod man that sucks

That vid sounded loud from the bottom

Test the cylinders that had the broken plugs first

 

If it is a rod knock and you pull the wire to the cylinder it should quiet down. At least it'll give you an idea.

Maybe, just maybe, there is something jammed in the cylinder that the piston is hitting.

Try pulling the wires then pull the head.

 

I haven't been able to test it yet since it has been cold and my work schedule. but if it is a rod, what kind of price am I looking at to fix. the engine only has 43k miles and I would rather not sell the truck. Would it be better to replace the rod or do an engine rebuild?

 

If it's just a rod bearing, find yourself a way to get the oil pan off and you could technically do it in the driveway with the right tools.