Hey everyone. I have a 2004 Monte Carlo SS, 66k and very well maintained. I am running Mobile 1 full synthetic with 89 octane fuel. I have been noticing a moderate strength gas smell for a while. It seems to be the strongest in the engine compartment and mostly during or soon after the car is running. I have had the system checked twice for leaks with the smoke test. I have even put it on a lift, started it with the remote start and looked for leaks, shut it down, restarted it, looked again...nothing. At this point, I am out of ideas. Could it just be running too rich? Does anyone have any ideas/opinions.... Your help is greatly appreciated!

 

You are N/A right?

Try using 87 octane, maybe you aren't burning off the 89 properly.

 

Correct, I am N/A and I was using 87 too and smelling it, so good guess but I tried switching already, which is why I am using 89 now. Thanks for the reply, apparently your the only one that reads my posts haha.

 

The only other thing I could think of is that your injector O-Rings are starting to go? Perhaps it's letting off the tiniest amount that you can't even notice?

Also you should just go back to 87, there's really no point running anything higher unless you are tuned for it.

 

I havent checked yet but I would think it is related to either my injectors or my fuel regulator. Somehow its leaking though and its starting to **** me off. I am only getting about 17 miles to the gallon, which is slightly below normal, atleast for my records.... Any way to check those other than pulling them out?

 

i get better gas mileage because of it. not to mention, cleaner on the car!! i dont use 7-11 though because theres is all the same somehow. but speedway has allways done me right. make sure all your spark plugs are in tight too. along with the injectors

 

I'm not going to have the argument about how if you car isn't designed to run anything other than 87 you are just wasting your money since your car isn't detonating the fuel at the proper time causing you to use more.

No real good way to test the o-rings than to pull them. Which you should just go get a couple packs of o-rings and some dielectric grease and replace them anyway if you are going to pull them out

 

alright, sounds like I have a project this weekend haha. Thanks for the help guys.

 

You can test the injector O-rings (and overall fuel system integrity) with a fuel pressure test gauge. If you connect a test gauge to the shraeder valve on your front fuel rail, run the engine, then shut it off, the gauge should maintain or SLOWLY release fuel pressure. If you see a rapid decrease in pressure, you have a leak in the system. The most likely culprit on a stock L36 is generally a failing injector O-ring, but a failing pump that doesn't prevent leak back or a small leak in line can cause the same symptoms. These are less likely.

Regarding L36's running 87 octane- sure, that's fine, but if you scan a stock L36 you'll actually see that they knock quite a bit on 87 at both part and WOT. While the knock really doesn't hurt anything, if you can resolve it you will experience overall better performance. Running higher octane generally eliminates or greatly reduces the knock you'll see and the engine will feel much stronger all around. This is assuming you're L36 is stock. If you're running a vendor tuned PCM or have a "performance chip" you definitely want to be on 91 octane or higher as these raise timing.

 

Hey i had a smell of gas in my car for about a week and then it turned out to be the fuel pressure regulator was bad when i first start it up there was just a dab of gas on top of the regulator just a suggestion....