Bad muffler creating vibrations/pulsing?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

HoosierJeeper

Gold Supporter/Admin
Staff member
Administrator
Joined
Jan 20, 2009
Messages
20,874
Reaction score
299
Location
Western WI
xc_hide_links_from_guests_guests_error_hide_media

Getting a pulsing/vibration feeling on acceleration, can definitely hear an exhaust leak. Up near the engine bay it sounds normal, walk around it and it's definitely louder at the muffler. Can a bad muffler cause a pulsing/vibration feeling while driving too? Engine seems to run fine, at WOT I don't feel it, it's more noticeable in the moderate load range. Just cruising it seems smoother.

Thanks!
 

KJowner

Full Access Member
Joined
Oct 20, 2022
Messages
1,397
Reaction score
790
Location
Uk
That sounds more like it's missing on 1 cylinder to me, or a massive leak on the exhaust manifold, but as it's quite at the front I'm going for a miss.
 

HoosierJeeper

Gold Supporter/Admin
Staff member
Administrator
Joined
Jan 20, 2009
Messages
20,874
Reaction score
299
Location
Western WI
That sounds more like it's missing on 1 cylinder to me, or a massive leak on the exhaust manifold, but as it's quite at the front I'm going for a miss.
Would a miss give me a CEL? Not getting any codes from it now.
 

KJowner

Full Access Member
Joined
Oct 20, 2022
Messages
1,397
Reaction score
790
Location
Uk
Would a miss give me a CEL? Not getting any codes from it now.
It should do, depending on the cause. I'd pull the plugs out and see if any of them are wet for a start. Or if you have a laser thermometer, one of my favourite diagnostic tools, check the manifold temperature at each port, you can easily see if one cylinder isn't firing.
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,180
Reaction score
1,827
Location
B.C. Canada
HJ- I'd definitely would want to get it up on a lift for a good inspection while running !
Hopefully it just needs a muffler ?
 

HoosierJeeper

Gold Supporter/Admin
Staff member
Administrator
Joined
Jan 20, 2009
Messages
20,874
Reaction score
299
Location
Western WI
HJ- I'd definitely would want to get it up on a lift for a good inspection while running !
Hopefully it just needs a muffler ?
That's what I'm hoping! Last Friday the upper radiator hose blew and gave everything a good soak. Drove fine after, parked it for the weekend and then drove it yesterday and got a flashing CEL and was running bad. Turned right around and pulled all the coils out, some had gotten wet so dried them off and the CEL is gone now. Engine feels smooth, just feel that pulse/roughness from somewhere. Muffler has been getting louder for the past few months, maybe it's a coincidence that it finally fell apart inside or something, but also I suppose wouldn't rule out a slight misfire, but have trouble believing that since there's no CEL. For as rough as the exhaust sounds you'd think there's be a code if there was a misfire.
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,180
Reaction score
1,827
Location
B.C. Canada
HJ- I'd also consider new KJ copper core spark plugs, NGK ZFR6F-11G if they have not been replaced in a while (35k Miles)
Here is the top rad hose part number for you as well. Hopefully still available I hope !!
Luckily I replaced my upper rad hose before it spewed everywhere. ;)
Only use Mopar Hoat Coolant or Zerex G05 in our Jeeps !
You must be registered for see images attach
 
Last edited:

HoosierJeeper

Gold Supporter/Admin
Staff member
Administrator
Joined
Jan 20, 2009
Messages
20,874
Reaction score
299
Location
Western WI
HJ- I'd also consider new KJ copper core spark plugs, NGK ZFR6F-11G if they have not been replaced in a while (35k Miles)
Here is the top rad hose part number for you as well. Hopefully still available I hope !!
Luckily I replaced my upper rad hose before it spewed everywhere. ;)
Only use Mopar Hoat Coolant or Zerex G05 in our Jeeps !
You must be registered for see images attach
Got the new hose already and it's full of Zerex G05, got all the store had LOL. Old hose was a Napa EPDM hose, 7 years old. Spark plugs are the right NGK ones, they have just under 30k on them.
 

u2slow

Full Access Member
Joined
Mar 6, 2012
Messages
743
Reaction score
162
Location
BC
If the muffler is old, it can be rusting, breaking-up and collapsing internally. I'm onto the 3rd muffler now in 12 years. (well, the 'middle' muffler lasted about 9 years.)
 

HoosierJeeper

Gold Supporter/Admin
Staff member
Administrator
Joined
Jan 20, 2009
Messages
20,874
Reaction score
299
Location
Western WI
If the muffler is old, it can be rusting, breaking-up and collapsing internally. I'm onto the 3rd muffler now in 12 years. (well, the 'middle' muffler lasted about 9 years.)
How did it sound compared to my video?
 

u2slow

Full Access Member
Joined
Mar 6, 2012
Messages
743
Reaction score
162
Location
BC
My stock muffler didn't sound like your video - was still dead quiet. It was rusted through externally, so I changed it. The next two have been louder/smaller aftermarket - a flowmaster copy was the 9 year one.
 

The Fixer

Full Access Member
Joined
Mar 22, 2009
Messages
96
Reaction score
11
Location
North Jersey
The original muffler on our '03 rusted through at the seam back in 2017, it had a similar sound to your video. The hole was on top, so we could hear it, but not really see it.

You must be registered for see images attach
After that, we had a Dynomax catback on it until 2022, which my son squashed wheeling some Blue trails at AOAA. He replaced that one with an MBRP catback, which sounds great.
 

Latest posts

Members online

Top