Fuel leak 99 3.1

[NullSmurf]

I had a classic coolant breach of the lower intake manifold. During the replacement process, I removed the fuel lines at the injector rails. During reinstallation, the supply side (installs horizontally) is still sloppy and leaks with the nut tightened all the way. I can only suspect I lost an o-ring or something.

Thanks for your suggestions.

[GTP Dad]

Welcome to AF!!

You are correct in your assumption that you lost or damaged an O-ring. You will need to remove the line and replace the O-ring and the problem should go away. You may need to go to a dealer to get the proper O-ring of course you can always check the parts stores since they carry a wide variety of them.

[NullSmurf]

Originally Posted by GTP Dad

Welcome to AF!!

You are correct in your assumption that you lost or damaged an O-ring. You will need to remove the line and replace the O-ring and the problem should go away. You may need to go to a dealer to get the proper O-ring of course you can always check the parts stores since they carry a wide variety of them.

Thanks, Brother! I've been dreading this. BTW, do you reckon the fuel test jig might be available for rent or 'borrow' from any of the parts chain stores? Yanking the upper manifold is getting old.

edit to add: I rechecked the Felpro gasket kit, the $100 one, and there were no fuel o-rings there. They did include one for the thermostat and two other mystery 1 inch plus o-rings.

[012620]

Originally Posted by NullSmurf

I had a classic coolant breach of the lower intake manifold. During the replacement process, I removed the fuel lines at the injector rails. During reinstallation, the supply side (installs horizontally) is still sloppy and leaks with the nut tightened all the way. I can only suspect I lost an o-ring or something.

Thanks for your suggestions.

How was the replacement process on the intake gaskets? My son has a 2000 Century and we will need to replace the gaskets in the near future. Thanks for any info.

[NullSmurf]

Originally Posted by 012620

How was the replacement process on the intake gaskets? My son has a 2000 Century and we will need to replace the gaskets in the near future. Thanks for any info.

Thank GOD for digital cameras. Document, document, and document. I'm not a pro, but I can take just about anything apart and put it back.

Mark your injector wires! The numbers on them do NOT follow cylinder numbers (numbers conveniently molded into the lower manifold). The harness that has the injector wires has a very exact route that you'll have to disrupt. Take PICTURES so you can put it back like the factory did. Get the $100 Felpro gasket kit - actually $89 from Autozone. Felpro claims to supply an upgraded gasket design that takes care of the inferior oem set. PM me if you get stuck.

Oh, and watch for those &&$^#% o-rings in the fuel connections (not supplied in the Felpro kit and neither was the throttle body gasket, but everything else was. The throttle body gasket was pristine, so I resused it. The Chilton paperback book - $20 was worthless for this procedure. I also noticed my torque wrench didn't go below about 20 foot-pounds. You'll need to torque the lower intake bolts to 150 inch pounds. "Need anything from Sears, honey? I need to go get a tool"

[richtazz]

MAke sure you lubricate the fuel inlet o-ring before attempting to reinstall, or it will roll over out of it groove and cause a fuel leak. Also, you do not have to unplug the fuel injectors. Disconnect the big wiring junction near the back of the alternator, and the injector harness will come out with the lower intake. IF you loosen the injector rail hold-down bolts, it will give you enough side-to-side movement to get to the long center lower intake bolts without removing the rail or injectors from the manifold.

012620

here's a link from the Grand Prix forums "tips and maintenance" sub-forum with a LIM replacement proccedure

http://www.automotiveforums.com/vbul...d.php?t=688015

[012620]

Thanks to both of you for your information. I also can take most things apart and put them back together again. But not always do I succeed but I sure give it a heck of a try. I usually remember how to put things back together but I have a problem with remembering the correct names of the parts. I have been known to say "hand me that d** thing over there".

In my next life I think I would like to be in some type of repair business. Maybe I'm nuts but the world needs repair people BAD!

[012620]

Which intake gasket set is best to use when replacing the old wore out uim and lim intake gaskets on 3.1 engine. The Dorman or Felpro. The Dorman complete set includes 8 manifold bolts for about $45.00. The Felpro complete set cost around $70.00 and does not included the bolts. Thanks for any info.

[NullSmurf]

Originally Posted by 012620

Which intake gasket set is best to use when replacing the old wore out uim and lim intake gaskets on 3.1 engine. The Dorman or Felpro. The Dorman complete set includes 8 manifold bolts for about $45.00. The Felpro complete set cost around $70.00 and does not included the bolts. Thanks for any info.

I found three versions - don't recall one with bolts. However, Felpro claims to use an upgraded material to the original OEM gasket. GM has a service bulletin out on them and GM also claims to have upgraded the material. The safe choice is to visit the GM dealer and buy theirs. I bought the Felpro.

Sidenote: thanks for the info on the o-ring. Lube was essential. The car now has about 100 miles on the job with no runs, drips, or errors.

[richtazz]

Nullsmurf, you're welcome on the o-ring tip, and thanks for the positive feedback. We appreciate hearing that our advice helped you out.

On which gasket set to use, I have seen the Dorman set, and all the gaskets look identical to the more expensive Fel-Pro set plus it comes with the new bolts. If I were going to do another of these intake jobs, I'd choose the Dorman set.