When I have my heater on and it's stopped & idling, I can smell gas through the heater vents. When I'm driving down the road, I can't smell any gas. My mechanic says that there are no gas leaks, and that it's actually oil dripping on to the exhaust and the fumes are coming into the car. He says I need a new oil-sending unit. Anybody else run into this problem?

 

i experienced that one morning when i had the heat on. thats like the only time ive used it though so i dunno.

 

oil sending unit? you think he means the Oil Metering Pump for the oil injection system? I would look around the engine bay for a leak. Burning oil doesn't smell anything like gas, so check the pulsation dampener. They tend to leak.

 

funny, I have been having the same problem and today when I went to get gas, the cap was gone... musta left it on the trunk last time and drove off....hahahah

 

been thru a few 7's they all smell like gas ...

 

mine smells like gas too, but it's from the almost empty gas can in the cargo area.

 

the weather strip around the end of the firewall near the hood line, or the shifter area.
if you have fume back flow towards the front, they can enter the car from those two area...

 

the vents draws outside air from near the windshield, thats the reason if fumes coming out of the hack of the hood, it will get sucked into the cabin.

 

Take this from me, a guy who has had a fire in his engine bay, get the car checked by a rotary mechanic quick! Most mechanics don't know how to check for a fuel leak on a 7! My first leak (fire) was caused by a bad fuel line under the UIM. Most mechanics won't pull the UIM and look. After I repaired that I was sorry I didn't replace the PD at the same time because a few weeks later it started to leak like crazy - I went straight to Mazda and paid $150 (installed myself, just like the new fuel lines) for a new one because one engine fire is one too many!

 

Your mechaninc doesn't know WTF he's talking about. Suggesting that burning oil smells like gasoline screams "MORON." Ask him what his degree's in? Dentistry?


To add to cman's post, look very closely at (or just plain replace) all of the lines from the fuel filter to the fuel injectors.

I have a remote starter on my FC, and a little earlier this fall I would use it to fire up my 7 first thing in the morning to warm her up. I'd left the heat up halfway and the fan on halfway so that the cabin would be warm.


Well, I'd get down to my 7 10 minutes later and the cabin would reek of gas. It turned out that the 6" line that went into the primary fuel injectors was leaking where it went over the injector rail nipple. The fumes would make their way out from under the hood, including the back of the hood where the air intakes are for the cabin heater. So, since I'd left the fan on, the fumes would get sucked into the car.


I replaced that line and Permatex'ed the connection.


Go find your leak! Then go find a new mechanic.

 

-could have said it better!

 

Thanks for your help. It looks like I'd better go look for the leak myself. I had a wire fire in my 2nd 7, so I know how that goes.

 

Geez....I really hope you've checked your pulsation damper....my car smelled like gas and the PD was leaking. Should be able to see a little bit of gas just under it...good luck. 86-88s are more prone...as I understand it.

 

I just ordered a new PD today. I'll have it on late this week or early next week. Even if it isn't the PD, I probably should change it anyway with 113K on it.

 

burning oil smells like gas? ummm no. no it doesn't.

as far as the smell of gas I think all of ours does that with time, seals are starting to get worn.

 

Anyone have any thoughts on a fuel smell coming from the engine bay anywhere up to 1 hour after driving my S4TII? Dosn't make much difference if it's driven hard or babying the throttle, or whether the weather is hot or cold. It's little worrying.

 

Bridge the 2 pin yellow connector that is on the Passenger side engine wiring harness near the airfilter. Turn the key to on (not start). This will run the fuel pump without running the engine. Much easier to look for fuel leaks without the heat of a running engine and the fan spinning.

Instructions for this are in the FSM as well.

Look directly on top of the engine rotor housings. There are lots of fuel lines there and the PD.

The car should not smell like gas. Mine hasn't in the last 10 years. I have been around an Rx with an under hood fuel leak. Made my garage stink from it just being in there a few minuets.