Engine smell when flogging it

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f1racer328

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I run my engine pretty hard (towing mostly) and have never smelled anything from it.

I had a leaky exhaust gasket on a different vehicle of mine. Sprayed soapy water on all of the exhausts connections (on a cold engine) and started it up, and it was obvious where the leaks were.

Like others have said, definitely try the recirculation mode and see if you smell it then.
 

powershift

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It could be an exhaust manifold leak but every one I've had made a tick noise whether the leak was against the head or the manifold exit connection.
 

LB Bill

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If it smells like sulfur (rotten eggs), and only when you really jump on it, it could be from the catalytic converter. Mine has done that to some extent since new, and my RRS did the same thing. Dissipates pretty quickly. It's worse when I haven't pushed it hard in a while. Doesn't mean the CC is going bad, but could be.

FWIW..Here's an explanation I found when I was concerned (my indy mech also checked it out and agreed-not too running rich or blow by).

"At hard full throttle there is a lot of fuel being dumped into the cylinders (a sudden rich mixture)and there can be minor incomplete combustion which lets some of the fuel get into the cat. The cat acts like a stove using that excess gas as fuel and they get hot. Get a big enough amount of excess fuel into a cat and a byproduct is hydrogen sulfide which smells like rotten eggs."
 

powershift

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It smells like the AF ratio is rich and not a sulfur or oil smell. I tried experimenting today but I couldn't stand on it long enough multiple times back-to-back to test with recirc mode vs without recirc mode. I think this might be a case for data logging with the JLR SDD Topix software that I'm bringing online.
 

16FujiDisco

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@LB Bill the smell I get sometimes is definitely a cat type smell, I just feel like it’s noticeable since the vents are always in fresh air mode. I’ll smell it too when another euro model car gets on it in front of me
 

Blueaz

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I notice a gas smell when I'm pushing it, especially off road on long uphills, washboards, bumps, etc. I thought maybe the fuel tank cracked flange recall wasn't fully corrected.
 

Jimmy Brooks

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Could be an exhaust manifold leak. Couple of people here found their manifold bolts sheared off.

I know one of my bolts sheared off because i found the spacer that sits in between the heat shield and the manifold itself wedged in between the cat and the cat heat shield. I also hear the slightest exhaust leak on cold start but goes away when warm (i assume the manifold binds back to the gasket when hot). Anyway I do get the sam wiff of something if I gas it while on the freeway and just assumed it was a little manifold leak. Not worried about it, don't plan on pulling the heads to get to them and no one would notice it unless I told them.
 

powershift

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I noticed a gas smell a few times while out today, but each time there was a gas station nearby. On the freeway making passes to 90 MPH, I didn't smell the stink like I normally do. The ambient temperature has dropped a lot. Now I need to wear pants and a jacket in the AM, about 60F and this afternoon it was only in the mid 90's.

I'm trying to get the SDD software working, it does everything except I need to learn how to use one last part lol. The live data logging is where I'm stuck. It will do programming too, but I'd like to measure knock to see if the computer is pulling the timing and adding more fuel because of knock. Its plausible that could be happening and as a result causing a rich exhaust smell.
 

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