What happened: A couple weeks ago, my son was driving the 85 IROC. It started losing power under light load and at speeds above 45mph. Came home immediately and parked it. Wouldn't start later that same day - noticed it was not making the usual fuel pump priming noise when trying to start it. Decided to tackle it the next day. Next day, it started right up. Drove it for a few miles. Started losing power under load again. Stopped in a parking lot. It died. Tried restarting - cranked super healthy, but no fuel pump priming sound. Possible Issue: Fuse, fuel pump relay or fuel pump. There is no in-line fuse, swapped out a 1988 IROC fuel pump relay into the 1985 IROC to eliminate that as the culprit. Still no fuel pump priming sound with the 88 fuel pump relay. Diagnosis: Bad fuel pump. Since I'm up in my years, and we have cold weather now, I wasn't about to do a Gen3 fuel pump on my garage floor (and I'm not comfortable cutting an access panel to the pump in my garage above a tank full of fuel). So, decided to tow it to a shop I have trusted for DECADES!! Their diagnosis: Bad fuel pump. So far, so good.

Work performed by shop: New fuel pump kit (sending unit, screen, pump, the whole ball of wax), and might as well do the in-line OEM fuel filter (fuel filter enters the chat) since that would be the pro thing to do.

Fuel Filter Blunder: Picked up the car. Drove the car about 5 miles when it started to lose power under load. Immediately drove it back to the shop. They looked at it and gave it a clean bill of health. Left the shop, headed home only to see what appeared like a liquid trail on the road behind the car. Got home, and while backing into the driveway, saw a stream of liquid pouring down the driveway. Got out to check. It was fuel gushing out of the bottom of the EVAP charcoal canister under the hood. Turned the car off immediately. Started looking under the car, and almost immediately saw that the newly installed in-line OEM fuel filter was installed back-asswards. There is, in plain sight, an arrow designating the direction of fuel flow, and the arrow is more than clearly pointing along the fuel line going to the fuel tank, when fuel flow is actually toward the engine.

What I think I know: The new fuel pump was trying to push the fuel "against" the in-line OEM fuel filter media, rather than "through it", causing a lean condition, hence the power loss. The fuel pump pressure that couldn't make it to the engine, had to go somewhere.....so it probably went back to the tank and forced fuel through the vent line, past the purge valve and out through the canister under the hood.

What I don't know: Did the media in the fuel filter get damaged? Did any fuel filter media debris get pushed downstream to the fuel rail, the fuel pressure regulator, or possibly to the injectors (two cylinders were misfiring - due to lean condition, but could it have been from filter media debris)? Did the over-pressure in the gas tank damage: any components of the new fuel pump assembly, the fuel tank itself, the gas cap, the fuel tank vent/roll-over valve, the purge valve, the charcoal canister, the vent tube, or any other fuel system component I may be missing here.

Trying to get my ducks lined up before I head out to discuss with the shop on Monday. I will update this thread as to how the shop handles it and what gets done. Thank you tremendously to anyone and everyone, in advance, for your time and sharing your expertise.

Jake

Picture reference aid: The arrow on the filter is pointing towards the driver's side of the car. The view is looking rearward toward the fuel tank.

 

I would throw a new fuel filter on and drive. Anything is possible, but doesn't seem too likely a new filter designed for high pressure would disintegrate into your fuel lines, even installed backwards. As for your other questions: impossible for the internet to know.

 

It is possible that the shop when installing the new fuel pump mixed up the canister vent and fuel return lines. They are very similar in size and side by side at the tank connection location, so an error could happen. That would explain the evaporator canister leaking fuel.

Now bear in mind this is a picture of a set of 1986 Firebird fuel lines and I don't know if the Camaro is different.

 

Horrible story! The shop you "Trusted for decades" installed the fuel filter BACKWARDS!

Then did not catch their mistake, when your brought it back, just driven 5 miles, exhibiting the same problem the shop charged you to fix.

I would install a new fuel filter, correctly, Then drain and dry the other filter and cut it open, to inspect the "media" for damage. I do not think it disintegrated, but I would not trust the errant shop to determine that.