'97 LS400 Fuel Odor
 

Guys, I wanted to bounce this issue off you for ideas. My '97 LS with 240k has developed a fuel odor under hood. It is very noticeable under hood and in the cabin when fresh air is directed inside. For you guys that remember carburetors, it smells like raw fuel when a choke plate is open and vapors escape under-hood. There are no visible leaks. No rough idle or performance decrease noted. Is anyone familiar with this issue with the LS engine? Can you tell me where to look for the source? My guess is the fuel lines are becoming cracked/brittle due to age and heat?
Is it possibly it is a crankcase ventilation issue? Thank-you in advance, John

I'd check the fuel pulsation damper on the fuel rail. The screw can come out of the end and the fuel will then leak out of the hole. I had this happen on my ES300 and research shows that the LS can have the same issue.

Part number- 23270-50012
https://cimg2.ibsrv.net/gimg/www.clu...ba634f4548.jpg

You might also want to look at your EGR tube behind the engine/ firewall area , fumes might be seeping in.. ( just a guess)

I really appreciate your suggestion Elless400. Regards,
John

Thank-you BillyDPowell, I will look into this also.
Regards

No problem John. If it's a fuel pulsation damper, you should easily see fuel leaking out of the top/end at the screw hole. I'm not sure what engine's in the picture below, this is just for illustration purposes. Why they opted for a Phillips screw in a hole I'll never know.https://cimg7.ibsrv.net/gimg/www.clu...7e601aed9.jpeg

Thanks again Elless400...do you know where this damper is physically located on a '97?

check here 23270... there are two of them

Thank you BillyD!

Excellent picture, Billy.

John, one more thing, you may have to run the engine to see leakage.