Ammonia Smell Under Acceleration

Smoothmarine!87

New Member
I have a Jeep Wrangler and whenever I accelerate hard, which is most of the time because it's a slow brick, I get a harsh ammonia smell. Everything I read leads me towards my catalytic converter going bad but there are other opinions as well. Has anyone else had this problem? Maybe I should go park it in Waldorf and hope that someone steals the CAT so that I can get a new one. :lmao:
 

glhs837

Power with Control
Which motor? Wifes 2015 3.2 liter has a slow leak from a valve cover gasket. Drops one or two drops a day onto the rear cat. Smells just like burning plastic.
 

Smoothmarine!87

New Member
Which motor? Wifes 2015 3.2 liter has a slow leak from a valve cover gasket. Drops one or two drops a day onto the rear cat. Smells just like burning plastic.
I have the 4L Straight 6. It's definitely not a burning smell. The smell of ammonia is so bad it almost burns your nose.
 

LightRoasted

If I may ...
For your consideration ...

I have a Jeep Wrangler and whenever I accelerate hard, which is most of the time because it's a slow brick, I get a harsh ammonia smell. Everything I read leads me towards my catalytic converter going bad but there are other opinions as well. Has anyone else had this problem? Maybe I should go park it in Waldorf and hope that someone steals the CAT so that I can get a new one. :lmao:

I would bet that you have an exhaust leak somewhere, that when under acceleration, which creates higher exhaust pressures and concentrated exhaust gasses, finds a weak point somewhere in the exhaust system and escapes. Which, by smelling it after and during acceleration, would most likely place that leak in the engine compartment area since you are moving forward and any exhaust leak post engine compartment wouldn't be detectable. Those gases you're smell are permeating, (and possibly through the A/C duct work firewall pass through), somewhere through your firewall area. So, pop the hood and inspect for exhaust leaks at idle and as well as revving up the engine a bit to higher RPMs to see if you can locate a leak.

Also, with upstream and downstream oxygen sensors, pre and post catalytic converter, if there were a converter blockage, you would be throwing a code and seeing a "Service Engine Soon" light on the dash.

Good luck and please report back if your find anything.
 

Smoothmarine!87

New Member
Thanks for the info, I appreciate it. Why would an exhaust leak smell like strong ammonia? Wouldn't you just smell exhaust?
For your consideration ...



I would bet that you have an exhaust leak somewhere, that when under acceleration, which creates higher exhaust pressures and concentrated exhaust gasses, finds a weak point somewhere in the exhaust system and escapes. Which, by smelling it after and during acceleration, would most likely place that leak in the engine compartment area since you are moving forward and any exhaust leak post engine compartment wouldn't be detectable. Those gases you're smell are permeating, (and possibly through the A/C duct work firewall pass through), somewhere through your firewall area. So, pop the hood and inspect for exhaust leaks at idle and as well as revving up the engine a bit to higher RPMs to see if you can locate a leak.

Also, with upstream and downstream oxygen sensors, pre and post catalytic converter, if there were a converter blockage, you would be throwing a code and seeing a "Service Engine Soon" light on the dash.

Good luck and please report back if your find anything.
 

Ken King

A little rusty but not crusty
PREMO Member
Thanks for the info, I appreciate it. Why would an exhaust leak smell like strong ammonia? Wouldn't you just smell exhaust?
Because a leak wouldn't allow for the gases to be completely burnt off as they go through the exhaust system. The smell could be from a problem with fuel injection system also. Run some injector cleaner through it and maybe some of that cat rejuvenation stuff to "sort of" clean the cat.
 

Smoothmarine!87

New Member
I guess where I'm confused is that my other car has zero emissions on it and it just smells like exhaust. Wouldn't Budds Creek just smell like a giant ammonia bomb? :lol:
 

LightRoasted

If I may ...
For your consideration ...

I guess where I'm confused is that my other car has zero emissions on it and it just smells like exhaust. Wouldn't Budds Creek just smell like a giant ammonia bomb? :lol:

The exhaust smells different for sure, but not with any ammonia. Those cars use different fuels and don't have catalytic converters either, just straight piped exhaust with perfectly tuned engines. Top fuel funny cars use nitro-methane, which has it own particular smell as well as will give your eyes a burning feeling if close enough.

I would check your exhaust manifold flanges at the cylinder head, and exhaust pipe flange for leakage.
 

LightRoasted

If I may ...
For your consideration ...

I have a Jeep Wrangler and whenever I accelerate hard, which is most of the time because it's a slow brick, I get a harsh ammonia smell. Everything I read leads me towards my catalytic converter going bad but there are other opinions as well. Has anyone else had this problem? Maybe I should go park it in Waldorf and hope that someone steals the CAT so that I can get a new one. :lmao:

Do you have an update on any remediation? Inquiring minds need to know.
 

Kinnakeet

Well-Known Member
For your consideration ...



I would bet that you have an exhaust leak somewhere, that when under acceleration, which creates higher exhaust pressures and concentrated exhaust gasses, finds a weak point somewhere in the exhaust system and escapes. Which, by smelling it after and during acceleration, would most likely place that leak in the engine compartment area since you are moving forward and any exhaust leak post engine compartment wouldn't be detectable. Those gases you're smell are permeating, (and possibly through the A/C duct work firewall pass through), somewhere through your firewall area. So, pop the hood and inspect for exhaust leaks at idle and as well as revving up the engine a bit to higher RPMs to see if you can locate a leak.

Also, with upstream and downstream oxygen sensors, pre and post catalytic converter, if there were a converter blockage, you would be throwing a code and seeing a "Service Engine Soon" light on the dash.

Good luck and please report back if your find anything.
Post engine compartment wouldnt be detectable???
Im going to disagree with that statement as it is not always true
 
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