Gas smell on start up - 2003

1. Did you verify that the engine oil cap is installed tightly?

2. Make the Prius READY, turn on the AC and depress the MAX AC button to force the gasoline engine to run, spinning the AC compressor. Inspect the injectors and fuel lines, looking for the leak.

3. If there's no obvious problem, I recommend that you take your car to another dealer. The fuel line is under pressure, at least 43 psi, and there must be a very small leak somewhere. Good luck.

 

Ok, the cabin air intake is located on the passenger side of the car under the shield that holds the wipers. You can see where I've snaked a data cable into the cabin:


It sounds as if the gas vapor purge line has a leak (or fallen off). Another, more disturbing possibility is a leak in the fuel injector lines. Regardless, given the effects of gasoline fumes, I believe this is a serious problem that needs diagnosis and correcting.

Suggestions:

1. Nose detector - with the hood open, rig up a plastic tube so you can 'sniff' the air at the other end. Start the car and using the tube find the strongest source of the gasoline odor. In a perfect world, a small pump exhausting the air from the tube works best and you may want to tape the free end to a small stick or cardboard tube so you can put it where you want it to go. The idea is to keep your body out of the compartment but detect where the odor comes from. Likely candidates: (1) PVC valve area; (2) fuel injector feed lines, and (3) evaporation lines that go to the manifold, air cover and throttle areas.
2. ScanGauge - most of the emissions systems are operated by the HV ECU and the ScanGauge has the ability to read out the diagnostic codes. Consider the $150-175 as not only a diagnostic tool but in the future, a tool for improving vehicle performance. Do build the adapter that w2co, vincent1449p and I figured out or send me a PM.
3. Find another mechanic - either another Toyota shop or independent. Sad to say, I don't know of any independent shops but there are some helpful Texas Prius owners who might be able to 'lend a wrench.'

I forgot to ask, what level of technical stuff with a car do you feel comfortable?

• Change flat tire?
• Change oil, wipers, plugs, or 12 V battery?
• Rebuild the engine and tranny?

The reason I ask is I want to communicate effectively and chat with you about the options. Where more details are needed, provide them. Where somethings can be assumed (aka., you have a VOM and set of metric wrenches) not post something that might seem obvious..

Bob Wilson

 

I suspect an exhaust system leak or another fuel system leak. I think further investigation is required. A gasoline odor should never be ignored.

I doubt that a "sticking" engine intake valve would cause this problem. If in fact the valve remained partially open during the compression, power and exhaust cycles, you would notice significant engine backfire and driveability issues.

 

I recognize that your car has been serviced 9 times total for this issue and the persistence of the problem is very upsetting.

I am wondering whether anyone put a fuel pressure gauge on the fuel rail? The spec is ~43 psi. After the car is made IG-OFF, the remaining fuel pressure is supposed to remain unchanged for at least 5 minutes. Has that been checked?

Have you been able to determine whether the fuel smell comes from the front of the car (i.e., the engine) or the rear of the car (i.e., the fuel tank)?

 

OK, then you can eliminate the fuel tank plumbing as a source of the gasoline leak.

I think it would be good to see if the fuel line pressure will be maintained when the engine is turned off. If the pressure drops, then maybe both of the original remaining injectors should be replaced (as you say that two were replaced in post #5.)

When the car is IG-OFF, you might remove the engine air filter housing cover and then lift out the air filter. Open the throttle plate by rotating the spring-loaded shaft. Now you can look into the intake manifold.

Do you find that the gasoline smell is especially strong, coming from the intake manifold? If so that might be a further clue that an injector is leaking fuel into the intake manifold. The fuel smell could pass through the air filter housing into the engine compartment.