Engine Oil Leak From Intake Manifold Gasket on Buick LeSabre

Problem Description and Possible Solution

The intake manifold gasket can develop external engine oil leaks. The intake manifold will need to be removed and the gaskets replaced to correct this issue.

Problem Data
RepairPal Verified
Average mileage: 110,178 (27,000–345,000)
16 model years affected: 1990, 1991, 1992, 1993, more1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
108 people reported this problem
Viewing 1 - 20 of 45 comments
I reported to the nearest dealer (Chevy, not Buick) that the driver side intake manifold melted in one spot and appeared to be caused by a coolant leak. Looked like coolant was dripping onto part of gasket extending outward of engine. Ten hours later (called dealer at 5:45 p.m.(cost for diagnosis is $79)told that replacement is needed for both plastic elbow tubes with o rings (tension assembly piece and motor coolant flow tubes), two intake manifold gaskets, a transmission gasket, and replace both rear shocks is estimated at $1500 (nothing in writing yet).

I am a little uneasy in letting this be done as I had to have a major transmission repair right after this dealer did a transmission flush (do not recommend at all) and I found transmission fluid all over the engine compartment and the engine a few days later.

Fix it. I plan to ask the service manager if they can do better and reduce the cost from $1500. If not, I will delete the rear shocks (do them myself at a local auto craft shop) and tranny gasket (no visible leaks anywhere)and see what the revised cost estimate numbers are.

Just for some fun, one phone call to a parts place produced the following: plastic elbows are $3.99 a pair; non-plastic gasket intake manifold kit is $299.00. And, the current on engine intake manifolds are make out of plastic....and I am totally surprised to hear that and am not keen on that at all. Now, intake manifold gaskets can develop engine leaks. Assuming these gaskets are the plastic ones that were not advertised to this owner by GM.

My budget is $1,000 but not $1500 with all the stuff added in. I would like to buy some X-mas presents, too, for children/families who are poor and not making it in this economy...etc.

I paid $36,000 for this vehicle (new) and these problems at 114,000 miles on a maintained vehicle makes me wonder why buy American or GM or I should trade in every five years. Trade it in seems to be the answer for me.
The intake manifold gasket leaks engine oil. Replaced manifold gasket to correct.
external oil leak and also internal- entering in the cooling system as evidenced in the resivoir.
Oil leak from intake manifold, not fixed yet.
i have replaced the plenum twice. the original plastic plenum was replaced with another plastic plenum from my friendly buick dealer by an independent mechanic. the second time around, about 2-3 years later, i bought a more durable plenum from a discount auto parts company, and it's still going. this "planned obsolescence" by GM really "upsets" me, but i'm not buying foreign ... YET!
loss of coolant, oil leaks, upper plenum to throttle body deterioration. installation of lower intake gaskets, upper plenum replacement at the same time.
replaced manifold & gaskets
leak anti freeze I read that anti freeze GM used was part of the problem dex-cool they lost a class action lawsuit I was taken to the weeds by the dealer for repair cost over $1200.00 had the same problem with a 1997 buick la sabre alimited and a 1998 lasabre they each went bad around 90000 cost me $850 each time they also were rust prone spent $4000 to replace rocker panels this is common for a Buick.
Engine oil leak. Replaced the upper intake plenum gasket per GM recommendation to fix problem.
I've had a great 2000 Lasabre bought with only 30,000 miles 1 owner (little old man who passed away). My mechanic (great great guy) told me these cars had poorly designed intake manifold gaskets and if I see signicant "gunk" on the bottom of the radiator cap... or signs of water in the oil, that these gaskets should be replaced with much higher quality ones. Actually, I had him replace the gaskets (It was $400 total) as a preventative measure. Not a problem at all for 150,000 miles until I totaled it in black ice one night in a multi-car pile up (The car was so well built that it took a huge impact and I walked away unhurt). I bought another one (because I needed a car quick for work etc.). I should have taken my time because at $4,800 and with 117,000 miles, it wasn't taken good care of (although it looked great and ran well). It's cost me a couple thousand in the last couple years in tires, struts, starter, etc, and now I see significant "gunk" on the underside of the radiator cap and the oil gets dirty too fast. So I need to replace it's intake manifold gasket and other stuff too. On the OTHER hand, realizing my errors in purchasing the 2nd Lasabre, and my dumb luck in finding the first one that I totalled, I spent 7 months on cars.com just "looking" at 2000 through 2005 Lasabres for sale. When I spotted one for $4,300 with 65,000 miles that had had the intake manifold gasket already replaced and other stuff too, we drove 240 miles and after driving it, bought it. Man, what a great car!! So the lessons for me were, 1. Lasabres need intake manifold gaskets replaced with much better ones as a certainty, never buy a car quickly but search for months for a well taken car of one for best price (only searching diligently will let you discover best price), and move quickly once it's found because I missed several great buys (after long searches) along the way by waiting a few days while someone smarter than me got to it first. These 2000 through 2005 Lasabres are amazing cars for the current prices. Just diligently internet search for one well before you find it AND get the intake manifold gasket replaced once you do automatically. GOOD LUCK!
oil leaking out of valve cover gasket
Intake manifold gaskets had to be repaired due to engine oil leak
Replaced plastic intake manifold. Milage and performance improved
Has already been fixed once around 70k on motor first time. Have oil leaking from now and oil has been looking like coolant is mixing in. Currently at 140k. Vehicle was maintained its whole life by older drivers.
Gaskets leaks oil. The engine needs oil every almost 1000 miles and i figured it is not oil burning. Just checked the gaskets and they leak.
Changed gaskets
Lower intake manifold gaskets both failed. I replaced them myself.
Leaking coolant
Water leaking external and internal had gaskets replaced my mechanic says very common problem the gasket he put in is an upgraded one he says will not leak again if you use the factory gaskets chances are it will do it again.
Had to replace intake manifold gasket with external leak just as gasket was breaking down which i was told by the mechanic would allow fluids to begin to leak internally. I was on a long trip and had it repaired at dealer without further incident.