Help! Gas smell coming from far left side of the engine bay.

I recently purchased a 2014 Tacoma TRD Sport with 134,000 miles on it.

TLDR: gas/exhaust(?) smell coming from passenger side of the engine bay near the fire wall.

The other day I was sitting at a light and I smelt gas in the cabin. Upon looking in the engine bay, I noticed that there was a heavy concentration of the smell coming from the far left side (passenger side) in the in the top corner near the firewall.

I’ve been doing a lot of searching and so far i’ve been led to think that it could be a faulty fuel pulsation dampener as this is roughly in the same area; however, after removing the air filter to get a good look at it, it seemed dry, with some corrosion but nothing that seems detrimental. On the other hand it could be an exhaust leak from the cat as it is in roughly that area.

To be honest with you I recently got into working on my vehicle and being interested in cars so I don’t have a whole lot of knowledge/experience to draw from; However, the biggest job I’ve done was a valve cover gasket on a Honda Odyssey so i’m not too afraid to turn a wrench. Any help or suggestions would be greatly appreciated. Thank you for reading and for any future help.

 

crawl underneath the truck, get a good flashlight and look for the leak. You should see some exhaust marks where the leak is coming from. I think you might be correct in leaning that way. Keep things simple at first

 

Honestly, my mind wasn’t really leaning towards exhaust leak but after looking up from under, it’s hard to see, but it looks like the underside of some clips and hoses have some carbon build up and they are above what I believe is the exhaust manifold. In addition, the back fabric material on the engine cover had black carbon deposits on it as well…

 

Some of the old timers use a cigarette lighter to find a gas leak, not advisable.

 

Not trying to sound rude but if you can't tell the difference between a fuel smell or exhaust smell it's going to be hard to narrow it down

In general, exhaust leaks are more common than fuel leaks

Look for black soot around the exhaust manifold and exhaust pipe connections

 

The intake for cabin air is in the cowling on that side of the truck.

Gas vapors and exhaust have two different smells for sure.

The only source of gas would be the fuel rails which are inside the V of the motor and there has been very few if any documented leaks in the fuel system on a stock truck in this area.

I'm voting exhaust leak. As there are many more likelyhoods of this happening in the area you described

 

I’m with you there in terms of the smells being different, it smells very, gassy if that makes any sense but I do see soot. I wonder if my engine is running rich on top of leaking from the exhaust manifold, hence the strong fuel smell present in the exhaust leak. I’m noticing fuel in the exhaust tip shortly after running the car.

 

You gotta oil leak?

 

That's your exhaust leak. Can you take a picture?

 

If the exhaust leak is bad enough the O2 sensors will get diluted with fresh air, the pcm will see the false air and richen the mixture

 

This is right above the manifold

 

Is the soot on the rubber hose? Check the flexible metal pipe for a crack. Might need a pocket mirror. Or stick your hand back there with it running and see if you feel hot air coming out

 

Looks like this pic is looking UP from the wheel well and at the firewall.

If you are not throwing any codes for emissions control or going into limp mode. Im betting this mating surface is your culprit. This is a pipe for the clean air injection on startup, The pipe/mating surface etc all see hot exhaust gases a but if there is an issue with the valves above (where the rubber hose attaches) there are pressure sensors that will throw a code.





I would (ON A COLD MOTOR). Have someone start the truck, hood open, and feel around the area gently for exhaust leaks where circled and where the pipe mates to the exhaust manifold itself.

If the leak is there we can help you with some part numbers.

 

I think you might have just saved me a lot of headache and money good sir. I felt around in there and I did feel a leak, followed it. I have a picture of where and the leak is visible. If anyone can help me find the part number for this, it would be greatly appreciated. The image is taken from directly below the black hoses shown below

 

It looks like the leak is on the SAIS valve side and not on the exhaust manifold side? IF SO The "gasket" is a metal crush washer / metal gasket of sorts. Toyota Part number = 17377-31010 grab two of em as they are cheap.

You are also going to want to grab some good penetrating oil to soak down that whole area for at least a day with how rusty those bolts look. My recommendation is AeroKroil makes PB blaster look like childs play. (WEAR GLOVES)

Aero Kroil Lubricant, Aerosol Can, 13 Fluid Ounces

https://www.amazon.com/Aero-Kroil-L...d=1696112530&sprefix=aerokroil,aps,138&sr=8-3

Probably want to replace those bolts too. ill bet M6 standard thread, get some 25mm long ones and you can cut them down if need be. But you could pull them out and then go to any hardware store in another vehicle too.

 

You are actually the best, I am deeply grateful for your and everyone else who has helped thus far for your time and knowledge.