Strong gasoline smell from exhaust - Third Generation F-Body Message Boards

V8 Slayer · 03-01-2005, 03:05 PM

I've noticed this lately,whenever I rev my engine or its idling in the morning warming up.A really strong smell of gasoline comes out.I could almost swear its pure gasoline.There's no actual gas coming out of the exhaust.I'm not getting a SES light.The car is a 91 Firebird with Dynomax Exhaust.

What could be the problem?

Project: 85 2.8 bird · 03-01-2005, 08:18 PM

check for pin holes in the fuel lines. has your fuel economy gone down too?

V8 Slayer · 03-01-2005, 09:44 PM

Fuel economy is horrible.How can I get holes in my fuel lines.Wouldent it leak then?
I never notice any fuel leaks.

Project: 85 2.8 bird · 03-01-2005, 11:24 PM

my lines running along the front frame rail were rusting. I had a nice fun time replacing them.

2_point8_boy · 03-01-2005, 11:34 PM

you ARE smelling pure hydrocarbons and you say that you smell it when you rev or when idling curing warmup, right? Well, the most likely case is that your CAT is dead and you are smelling what normally comes out the end of our cars. the times that you are describing is when the engine is open loop. My CAT is completely hollow and and I have the same symptoms that you're decribing, the poor milage is probably unrealated to this, but then it again, it could be. Do you have any other symptoms like hesitation, bogging, overheating, pinging, bucking or surging, or anything like that?

Do you smell it when you are idling AFTER warm up?

V8 Slayer · 03-02-2005, 01:34 PM

Quote:

Originally posted by 2_point8_boy
you ARE smelling pure hydrocarbons and you say that you smell it when you rev or when idling curing warmup, right? Well, the most likely case is that your CAT is dead and you are smelling what normally comes out the end of our cars. the times that you are describing is when the engine is open loop. My CAT is completely hollow and and I have the same symptoms that you're decribing, the poor milage is probably unrealated to this, but then it again, it could be. Do you have any other symptoms like hesitation, bogging, overheating, pinging, bucking or surging, or anything like that?

Do you smell it when you are idling AFTER warm up?

My car does hesitate like 1/6 times I "get on the gas".

I dont have any other symptoms like overheating or pinging but yes I do smell it after warmup,just not as strong.

91blue_fire · 03-02-2005, 11:02 PM

yeah man, i have those problems. its a 91, 3.1 like yours. i can smell it inside too. i get like 230 out of a tank. i smell it at red lights. it sucks man. but...my cat should be good. i passed emissions 5 months ago, when it smelled like that, fine. mines under the hood though. can u smell it under the hood?

V8 Slayer · 03-02-2005, 11:04 PM

Mine passed emissions about a year ago with awesome results.I can also smell it at a redlight and inside the car,not under the hood though.Ill be lucky if I get 200 per tank....

85berlinetta2.8 · 03-03-2005, 02:54 AM

thats terrible gas milage. as well as hesitating, theres a problem

you may be running rich, say timing might be off, or a sensor dumping too much fuel... or you may have a hole in the tank or line...

V8 Slayer · 03-03-2005, 11:58 AM

But yet theres no SES light.

85berlinetta2.8 · 03-03-2005, 01:17 PM

timing wont throw a code

V8 Slayer · 03-03-2005, 01:56 PM

Next time I go to get an oil change ill ask them to check the timing...Should it cost extra?

What should the timing be set at?

85berlinetta2.8 · 03-03-2005, 03:16 PM

depends on where you get your oil change at. i dont think people at quickie lube places would know how.

V8 Slayer · 03-03-2005, 03:54 PM

Goodyear?

TomP · 03-03-2005, 03:57 PM

Buy one of these http://www.harborfreight.com/cpi/cta...temnumber=3343 and check it yourself!

85berlinetta2.8 · 03-03-2005, 04:00 PM

wow i had no idea they were that cheap. i bet they would charge you 20$ to have it checked

V8 Slayer · 03-03-2005, 04:01 PM

I wish it was that simple and I could do it myself.....

2_point8_boy · 03-03-2005, 08:51 PM

Quote:

Originally posted by 85berlinetta2.8
wow i had no idea they were that cheap. i bet they would charge you 20$ to have it checked

that's because that is a crappy light. It doesn't have any advance or RPM functions. Unfortuantly, wiht tools, you pretty much get what you pay for. If you're just a backyard mechanic and don't plan to be really using it that often, sure, by all means, buy this one. But I do not recommend it if you plan on using on multiple cars because most cars simply have a needle and a mark on the pully.

anyway, back to the original post...a hesitation is USUALLY caused by a lean condition. that could also make you smell the gassy exhaust because you have a slight lean misfire. it'll do the same thing as being rich, but if you were so rich that you were hesitating because of flooding, then you would get puffs of black smoke. Things to check from here: O2 sensor, TPS and Fuel Pressure. If you like, you can buy a tool from some places that plugs into the injector harness, then you turn the key to "on" then hit the button on the tool. It pulses the injector for a pre-determined amount of time and you get a list of common pressure drops in the fuel system. That'll tell you if you have any bad injectors and you can do it without having the car running, which is a good thing because in order to reach the injectors, you have to remove the upper plenum.