Fuel leak from back of engine

I seem to have a possible fuel leak or exhaust leak. The kicker is that once the engine gets up to temp, I no longer smell it.

Background: recently I had my Tacoma in for replacement of the timing cover gasket at 101k miles. They also discovered the head gaskets and water pump were all leaking. They had the truck for over 2 weeks and fixed those issues under my platinum warranty.

After getting the truck back, I began noticing the smell the next day after pulling the truck into my garage to try and diagnose a squealing sound that seems to be a belt issue, but the belt has zero signs of wear and the squeal doesn't last that long when in park.

Before you say "take it back to the dealership." I know. I already did once and plan to again. They tried putting some belt dressing on the belt (which didn't work) and said they couldn't replicate the smell issue. The squeal wouldn't last long enough for them to get any sort of diagnosis on it. This is more or less to get some ideas as to where to look. I'm hoping it's something simple, like they forgot to fully tighten something. Hopefully to give them a better idea where to look.

I've traced the fuel lines as best I can without taking things apart and everything I can see, including connectors, look bone dry. I can't see any signs of moisture around the fuel injectors either. I also tried feeling around the exhaust pipe connections and where the headers meet the block and didn't feel any air coming out and could only feel the radiator fan breeze. The smell seems stronger on the driver's side and, again, seems to go away after the truck is up to operating temperature.

Update: spoke with the dealership today. The official explanation for the fuel leak was that an O-ring went bad in the injector system and it was not related to the previous repairs. They replaced all of the o-rings under warranty as a precaution. I suppose this would explain why the leak sealed up after a few seconds. As if the fuel caused the O-ring to swell up again.

As for the squeal noise: they still can't get the truck to do it long enough for them to be able to tell what it is.

Update #2: I picked up the truck today. The official explanation for the leak was an O-ring that went bad on the direct injector fuel rail on the back side of the "left hand side" of the engine. They replaced all O-rings and have not seen any leaks since.

 

https://www.tacomaworld.com/threads/18-tacoma-fuel-leak.730776/ Theres' two sets of these fittings, one near the brake cylinder under the hood and one forward the gas tank, they can both leak like this example.

Injectors can leak from being disturbed as well.

 

Fuel pump there was a recall announced like 3 weeks ago “if you smell fuel….”

 

Not a recall.

It is a Warranty Enhancement Program for the high-pressure fuel pump low-pressure fuel seepage.

 

I saw that post and have checked both of those and they are also bone dry. I also saw a similar thread about the fuel injector rail and have not seen any signs of moisture around any of that either. At least what I can see.

 

Bring it in for the fuel pump get a free diagnosis

 

I've heard of the fuel pump recall, but this one is new to me. I have checked all around the high pressure fuel pump as best as I can too and haven't found anything wet. Plus it doesn't make sense to me that it would stop when the engine warms up. The odor is also stronger on the driver's side. I plan to try and watch the engine and underneath when I start it up for the first time tomorrow morning.

 

yessirrrrrrr!

 

Update:

It's definitely a fuel leak. Upon starting it this morning, it was pissing fuel down the back of the block but I still couldn't see from where. Photos were taken after it had already sealed itself and stopped leaking. It is much more dry in the photos than when it was occurring

 

Yup you can clearly see it

 

It is so refreshing to hear that an auto-dealer actually honored a warranty - and especially an extended warranty!! Nice.


Remember that normally items contract when cold and expand when hot. Could be as simple an explanation as that. Maybe.

 

That is why these constant tension clamps are superior; don't bitch, man up, and buy the correct tool for them.

 

I would call the dealer and have a tow truck come pick it up. That could burn the truck to the ground. I would not park too close to your house either. Probably something stupid like a line not tight or inserted all the way but let THEM figure that out.

 

??????
You lost me with the comments about bitching, manning up, and correct tool.

(I had only offered a reason as to why his problem went away when his engine got hot.)

 

My reply to the general statement of hot and cold shrinking and swelling. Add in how many people bitch about those clamps and say that a worm gear clamp is better.

 

Thanks to those who have left helpful comments. My point in this is to try and find the issue so I can point the dealership in the right direction since they told me already that they couldn't replicate it.

Today it appears to be coming from some black fitting that connects to the rear of the block. I can barely see it around the transmission and exhaust from below and can't seem to find it at all from above. Does this ring a bell to anyone?

 

There's high pressure fuel lines that get removed during the timing cover job, its likely one is leaking. They are difficult to see but they are near the firewall.

 

CYA, and send them an email or something that can be later documented. It’s a huge liability to have fuel spray. Frustrating they’re not taking this more seriously.

 

We've had a few conversations over text since the warranty work, along with a follow up appointment. I sent another message as well with updates.

 

Thanks for the help. Do you have any more info on those? I can only seem to get info on the 1st and 2nd gen ones but I know they exist.