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Noxious Bimmer

I drive a 1987 BMW 325i and I’ve been smelling gas fumes from inside the cabin. It’s very noticeable when I roll down my windows and the heater is on vent. My heater core isn’t blowing so it’s the only way to get warm air. My question is: Is this a potential health risk?

Yes…it can be. The vehicle is leaking exhaust fumes or gasoline. You need to find a good mechanic to check the vehicle out completely. It may be a simple problem like a saturated charcoal canister or it may be something that can harm you or your passengers. Leaking gas or carbon monoxide can both be fatal. I would start looking for that mechanic right now.

By ‘gas’, you mean gasoline? Not exhaust? Yes, it’s a health risk (either way, really). If it’s gasoline fumes, you have a leak somewhere, potential fire (very unhealthy). If it’s exhaust, you risk carbon monoxide poisoning. Have it checked out soon.

Yes. First of all, gasoline fumes are hazardous. You should not be breathing them.

Secondly, gasoline fumes indicate a leak, and leaking gasoline can cause a fire.

Have a mechanic locate and repair the leak before something bad happens.

If it smells of gasoline, first check the hoses to and from your fuel filter. I think your fuel filter is in the engine compartment, driver side, near the firewall, beneath the power brake assembly.

If it smells of exhaust, kneel down and listen beneath the car. Can you hear any leaks? Can you stick your hand under there and run it along the pipe (not touching, hot!) and feel for evidence of leaks? Pay particular attention to all joints from the engine to the catalytic converter.

My catalytic converter looks rusted/ broken. I found no leaks from the fuel lines. It’s a manual and the gasket that’s supposed to go around the shifter to the car is missing, I think it’s coming in from there. I’m now certain that it’s exhaust fumes rather than gasoline. Can I just cut out the Cat. and put a union in?

I don’t know where your oxygen sensor attaches, but I am guessing that you could probably put a straight pipe in place of your catalytic converter. The change in back pressure will affect the way the EGR works, but I doubt it will cause the computer to set a code.

I presume that you live where there is no emissions inspection?

If you do it right and replace the cat, on your car, the whole exhaust from the manifold back to the muffler is sold as a single piece. It is about $1600 at the dealer and about $400 on-line.

You definitely do not want to keep driving it the way it is now. CO will kill you.

I look at replacing the catalytic converter with a straight pipe like cheating on your taxes: good for you (as long as you don’t get caught), bad for everybody else.