Fuel Leak

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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3800SERIESII
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Fuel Leak

Post by 3800SERIESII »

Noticed fuel leaking right under the passenger rear door. It is a drop every 20 seconds or so. I am pretty sure the leak is coming from the line from the tank to the engine or wherever. Not sure how many lines there are...

Additionally, what would the difficulty run for a "DIY" kind of person?
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Re: Fuel Leak

Post by justdave »

Sorry to say, but if you have not ALREADY found your very dangerous fuel leak, and fixed it...you should not be attempting to fix it, and should not be driving your car. Some vehicle repairs are critical Safety Issues, not to be attempted by the DIY/amateur; this is one of them. Make an appointment at a NEAR-by repair shop, and either have your car towed there, or drive it DIRECT-ly to the shop, calling ahead to alert them that you are coming in with an active fuel leak(!). You should have a large fire extinguisher with you in the vehicle that is Rated to put out Gasoline fires...and do not smoke while driving there, and do not let any other customers smoke near your vehicle when at the repair shop!
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Re: Fuel Leak

Post by myfirstbonnie »

Put the car on jack stands and verify what and where it is leaking. I am not sure on the 92-99, but the 2k and 89, the fuel lines run down the driver's side.
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Re: Fuel Leak

Post by 94SilverSSEi »

92-99 the lines come off the top of the gas tank and run down the rear frame rail and them along the passenger side of the car.


I can't say for sure what is leaking on your car but on our 1994, the lines were actually leaking where the metal line attached to the plastic gas line because the rubber connector had rotted away. (You be lucky if thats all it was). Some tranny hose and a few connectors and it was "fixed." Only to find that the metal line up my the gas tank was so rusty, it too was leaking.


Take a peak at the lines, but don't be surprised if you end up dropping the tank.


That's why I've held off on ever changing the fuel filter on my 1997, in fear of breaking these gas lines.
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Re: Fuel Leak

Post by reb »

Very simple, crawl under the car and look. Its either the gas tank itself or one of the lines.
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Re: Fuel Leak

Post by Jfridge92 »

Yep, fuel filter is right in that area near the front and rear passenger side as well, it's probably leaking somewhere in between the line that runs from the tank to the filter.
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Re: Fuel Leak

Post by MattStrike »

If you need to replace a section of the nylon line, you can get a repair kit and separately find these:
MattStrike wrote:... you can find 'push-to-connect' fittings from dorman for each size. It's really easy, cut out the broken section and fit a new piece in, and push into the fittings. 800-192 is the 8mm, $10 a pair.

8mm
10mm

Of course, use a calipers to measure the OD of the line, to verify if you have metric or SAE. I didn't, and found out mine were metric.
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Re: Fuel Leak

Post by 3800SERIESII »

So it can be done... Was worried about the $500 shop charge (about half of what the car is worth).

So many responses. Good news is that it IS between the tank to the filter. I too was scared of changing the fuel filter about 10,000 miles ago and will probably hold off for the fear of creating problems.
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Re: Fuel Leak

Post by motopsyco »

I'd say since you got a leak anyways and will have to replace a line, go ahead and change out that filter since if anything is gunna break, might as well have it happen when you have to replace parts anyways. And fuel lines are something a diy'er can do themselves, just as long as you use the right parts and tools for the job
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Re: Fuel Leak

Post by reb »

The high pressure line from the fuel sending unit quick connect to the filter can be very stubborn to release from the sending unit end and often breaks in the process. The line is one of the few you may find stocked at your local dealer.
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Re: Fuel Leak

Post by RPACODY »

I agree with motopsyco - change the FF and see what line is leaking , probably anound the FF connections .right under the passenger door is the fuel filter
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Re: Fuel Leak

Post by John Deere Boy »

Yep the line is patchable. I had a critter chew through mine in the same area. Patched it with the fuel line patch kit from carquest. No problems after four years.
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Re: Fuel Leak

Post by repinS »

Several members in the past (myself included on my 95 SSEi) have had this leak. More often than not you're looking at having to replace the entire fuel tank sending unit. The steel lines like to rot out and the leaked fuel trickles down the line and hits the ground right behind the fuel filter. The order of fuel flow:

Tank --> Pump --> Sending Unit & Steel Lines --> Quick disconnect/Nylon Line/Quick disconnect --> Fuel filter

I used double-clamped rubber hose in lieu of replacing the nylon line, because I mangled the quick disconnects upon removal. You will have to drop the tank to do this.
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Re: Fuel Leak

Post by 3800SERIESII »

Sounds exactly like the issue i have. The leak is coming from the line but more up towards the tank and the fuel trickles down the line and drips where the line bends before the fuel filter.
1999 Pontiac Bonneville SE- Stored -All stock, Sony CDX-GT570UP HU w/ Scosche HD 6.5"'s front/Alpine S 6x9 rear, 153,000 miles
1996 Pontiac Bonneville SE- Now a parts car - HAI, Muffler Delete, Summit Y-pipe, 250,000 miles
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1997 Pontiac Firebird - DD - 3800 Series II, Cold air intake/FWI, Y87 Package, Sony DSX-S100 Digital Media Reciever, 180,000 miles
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Re: Fuel Leak

Post by repinS »

You can contort a bit and look at the upper quick disconnect on the nylon line. If you can determine that this or the nylon line isn't leaking, you probably need to drop the tank and swap out the sending unit. It'll look like this:

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09 Lexus LS460 AWD -- 94,000km -- Daily Driver
09 White Hot G8 GT -- 155,000km (fuelly) -- LS3 Cam -- GM LS3 CNC Ported Heads -- Kooks 1 3/4" Long Tube Headers -- Solo Catback Midsection -- Hooker Maxflow Mufflers -- Pat G Tune -- Rotofab Intake -- Tein S-Tech Springs -- GXP FE3 Dampers -- BMR Subframe Cradle Inserts -- BMR Subframe Connectors -- Forgestar F14 Gold 18x9 +40 -- Michelin Pilot Super Sport 245/45/18 -- Maverick Man Carbon Fiber Spoiler
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