Rattle

[PJV5]

I have a 1996 ford ranger 4x4 with a 4.0. About a week ago I started hearing a rattle when accelerating on the highway and up hill. There is no loss of power, no codes, no issues with exhaust/heat shield and no issues with the cat converter. I have 130,000 on it. Any thoughts? Thanks

 

[slater50]

cat converter honey comb in know to rattle internally if compromised...
Could it be dedonating / pinging on take-off, acceleration?

 

[PJV5]

Went to exhaust shop yesterday they said the cat looked fine. I have plenty of power and rattle lasts only a few minutes while getting up to speed. I'm worried about driving it

 

[PJV5]

It was my dad's truck he doesn't think it's ever had the spark plugs changed

 

[scotts90ranger]

Misfires put air fuel mixture into the exhaust that burns in the cats and likes to melt them... they can look fine externally but still be melted... Misfires can and are normally caused from failed ignition components like having old plugs and wires... I'd start with a tune up and go from there.

That said if the rattle is tinny the cat heat shields on these are known to break, the official Ford fix is big hose clamps around the middle...

 

[I support common sense]

Maybe if you could get some kind of recording? Honestly sounds like the honeycomb or the heat shield around the cat.

 

[slater50]

It was my dad's truck he doesn't think it's ever had the spark plugs changed

if it wasnt rattling at the time the shop checked it, theyre not going to find it....
sometimes the honeycomb is wedged & doesnt make noise...
as it heats up & everything expands, exhaust turbulence, etc, the HC gets loose & rattles...


this is just a guess, as stated a video would be great...

Been a ford engine tech for 32 years, ive heard everything atleast a few times...

 

[Terrys87]

Check all your rubber and plastic. Shock mounts to door pin striker. Your window trim can cause your window to vibrate if truck is lugging causing vibrations. Sounds like a tune is needed. Heat shields are common. Motor mounts, sway bar bushings, exhaust hanger brackets are just some I can think of right off.

 

[Uncle Gump]

Starter bendix letting the starter gear hit the flywheel.

 

[PJV5]

Thanks for all the input it's greatly appreciated! I think I'll start with a tune up with new plugs and wires and will update with results. Update the plugs and wires looked good. Just got a po 420 code bank 1. Both o2 sensors were replaced about 2 weeks ago. Do I need to replace both cats or can I still drive in an emergency