Hello all!

I am both new to the forums and to owning a Lexus. I just got my 97 LS400 yesterday morning. I've been looking for a good one for about 3 months now and following these forums closely. I am impressed with all the knowledge you all share and will rely on it a lot as I enjoy this new experience.

So far, the only problem I am experiencing is the smell of exhaust (mixed with the smell of gas) when I am stopped at a traffic light. If I turn off the flow through ventilation, it goes away.

I've looked under the hood and I can't find any signs of a fuel leak anywhere.

Any ideas? Is this something typical or common? I don't see a thread on here to indicate it is.

Other than that, I now totally get why people love these cars. Mine has 112,000 on the clock and I hope to take her way beyond the 200,000 mark! It's a Champagne Pearl model with the Coach leather package. It doesn't have the air suspension or the Nakamichi sound system. It appears to have everything else (including electric head rest adjusters). This was the perfect Christmas gift to a 52-year old man!

Thanks for any help you can offer!

 

Congrats on the LS and welcome.

My thought is the EGR tube is cracked and the exhaust gasses are being released within the engine compartment. The other check is if the car is running rich, can you pick up the same odor from rear of the car?

 

A couple things to look at-
Inspect the entire exhaust from the header back. There may be a crack or some rust along the pipe allowing exhaust to escape. (i had a large hole in mine from being lowered, CEL never came on, and it passed smog.)

Check the fuel lines and pump.

Look at the injectors. I have seen a couple instances where hairline cracks in the injectors, or old seals have created small fuel leaks.

Make sure to check all your hoses/vacuum lines. Sometimes there could be a small leak in a return hose that will allow the exhaust or fuel vapor to escape.

A visual inspection should give you a good idea as to the condition of all these items.

 

Do you hear any exhaust noise? It would sound like a clicking if its a small leak. And if it is exhaust you could be Co poisoning yourself too, its a good idea to fix it fast. Also if hot exhaust is leaking from a cracked egr tube and blowing towards the fire wall it can damage stuff and start a fire too.

 

The EGR hose was cracked. Replaced it and the problem seems to have gone away. Thanks for all the suggestions.

 

Glad that you found the problem.

 

Well, I thought I found it. Tonight the smell is back, but more a raw fuel smell and not exhaust. Only when I am at a stop light for a prolonged time. I can't find any fuel leak anywhere. Surely there is some sort of evaporative container under the hood...but I can't find that either. Maybe this weekend I'll have some daylight and time to search further. Any ideas?

 

In your prior post, you claimed to have found it with a cracked EGR hose? Did you mean EGR pipe. It is made of metal and I wouldn't describe it as a hose. Did you mistake what you changed as the EGR pipe? It is attached to the rear coolant bridge and then goes down to the exhaust and is quite difficult to change.

 

What I replaced was a hose from the left side of the breather that went to the right side of the engine near the battery. From the location on the breather I may have mistaken its purpose. I may be 52... but I'm still learning.

 

Dude, it sounds like an exhaust leak maybe from one of the joints between the exhaust and the cats. Sometimes a hairline crack doesn't leak until the pipe gets hot and expands.

 

Okay,
In my Audi there was an evaporator canister that fuel vapor would be cycled through before it escaped into the atmosphere. Mine went bad after 110k miles and it made the smell of raw fuel very apparent after the car was warm and fuel system pressurized.

Just a thought, but perhaps there is a similar system in the LS?

 

Or his evap system is leaking as well

 

With little auto repair experience and tools you might want to turn this over to a professional. Those fumes can't be good for you and potentially leaking gas is not a good thing.

 

I found it! The rubber (kinda "S" shaped molded hose) fuel hose had a cut in it right where it met the flange on the metal tube from the tank. It was dripping on the exhaust manifold. Talk about luck! I'm amazed it had not lit on fire already. After the replacement was installed I drove if for an hour and the manifold was dry and the fuel smell gone. After Legender mentioned the leaking fuel possibility I started to trace the lines and found it in short order.

 

And from experience, gasoline can drip on a hot exhaust manifold and not burn, where if it was hydraulic oil it will light right up, yeah I know no one will believe it.
I spent many years around old bulldozers so...and lived it many times.