1999 Buick Lesabre engine and engine cooling problems

“ANTIFREEZE LEAKING INTO ENGINE THROUGH INTAKE MANIFOLD PLENUM CAUSING EXPENSIVE REPLACEMENT ENGINES AND OR PARTS. DANGEROUS IF ENGINE LOCKS UP WHILE DRIVING. *TR”

“CAR WAS GETTING HARDER TO START EACH TIME- RED LIGHT (OVERHEATING) CAME ON WHILE ON A TRIP- ADDED 4 + QTS OF WATER- DROVE 15 MILES- CAR WOULD NOT START--ADDED 3 + QTS OF WATER--TRIED SEVERAL THINGS TO TRY TO START--NOTICED OIL LEVEL WAS UP-- ASSUMED COOLANT WENT INTO ENGINE- REMOVED 3 FRONT SPARK PLUGS--COOLANT RAN OUT OF SPARK PLUG OPENINGS- CAR WAS TOWED 60 MILES- INTAKE MANIFOLD (WARPED), GASKETS, & THERMOSTAT WERE REPLACED- STARTER REPLACED DUE TO BROKEN HOUSING (FROM ATTEMPTING TO START WATER LOGGED ENGINE)- TOTAL EXPENSE APPROX $ 1,000”

“ENGINE SEIZED AND WOULDN'T START. FOUND THE INTAKE MANIFOLD FULL OF ANTIFREEZE. CAUSED BY A FAULTY INTAKE MANIFOLD. REPLACED MANIFOLD, CHANGED OIL AND ANTIFREEZE AND REPLACED CRACKED STARTER. *TR”

“THIS CONCERNS A DEFECTIVE DESIGN OF THE INTAKE MANIFOLD USED BY GM ON 1998, 1999, 2000, AND SOME 2001 BUICK LESABRE'S EQUIPPED WITH THE 3800 SERIES II V6 ENGINE. FOLLOWING THE FAILURE AND RESULTANT HYDRAULIC ENGINE LOCK OF A NEIGHBOR'S 1999 BUICK LESABRE WITH APPROXIMATELY 80,000 MILES ON THE ODOMETER, I VISITED OUR LOCAL BUICK DEALER (LEE CHEVORLET/BUICK - WASHINGTON, NC) TO DISCUSS WHAT APPEARS FROM RESEARCH DONE VIA THE INTERNET TO BE A FREQUENTLY ENCOUNTERED PROBLEM ON THESE VEHICLES SO EQUIPPED. IT SEEMS THAT A FAILURE OF THE INTAKE MANIFOLD IS A VERY COMMON PROBLEM ON VEHICLES WITH ABOUT 80K MILES ON THEM, MY WIFE DRIVES SUCH A VEHICLE - A BUICK LESABRE LIMITED PURCHASED FROM LEE CHEVORLET, WASHINGTON, NC ON 2/24/99 IT CURRENTLY HAS 78,000 MILES ON THE ODOMETER. THE DEALERSHIP OWNER, AND THE SERVICE MANAGER FREELY REVEALED THAT THIS IS A SERIOUS AND CHRONIC PROBLEM WITH THESE VEHICLES AND IS THE DIRECT RESULT OF A POORLY DESIGNED PART USED ON THEM. THEY ARE PRONE TO FAILURE AT ABOUT THE 80K MILE POINT WHICH RESULTS FROM AN INTERNAL (NOT APPARENT) FAILURE DUE TO MATERIALS DEGRADATION. THE RESULT IS VERY FREQUENTLY THE DISCHARGE OF ENGINE COOLANT INTO THE…”

“TL*THE CONTACT OWNS A 1999 BUICK LESABRE. THE CONTACT STATED THAT HER VEHICLE SHUTS OFF AND FAILS TO RESTART. HOWEVER, WHILE DRIVING AT AN UNKNOWN SPEED, THE VEHICLE SHUT OFF AND THEN RESTARTED IMMEDIATELY. LATER THAT SAME DAY, THE CONTACT STATED THAT THE VEHICLE WOULD NOT RESTART FOR APPROXIMATELY AN HOUR AND A HALF. WHILE IDLING AT A TRAFFIC LIGHT, THE VEHICLE SHUT OFF AND TOOK 15 MINUTES BEFORE IT RESTARTED. THE FAILURE CONTINUED TO RECUR INTERMITTENTLY. THE VEHICLE WAS TAKEN TO AN ELECTRICAL MECHANIC SHOP, BUT THEY COULD NOT IDENTIFY THE CAUSE OF THE FAILURE. THE VEHICLE WAS ALSO TAKEN TO FIRESTONE AND REPAIRED; HOWEVER, THE FAILURE RECURRED. THE FAILURE MILEAGE WAS 55,000 AND CURRENT MILEAGE WAS 58,439.”

“WIFE'S 1999 BUICK LESABRE WITH 90,000 MILES ON IT WAS BURNING ANTIFREEZE IN ENGINE. I WAS TOLD BY A CERTIFIED GM MECHANIC TO TRY TIGHTENING THROTTLE BODY MOUNTING NUTS BECAUSE BEING TOO LOOSE WAS A COMMON PROBLEM FROM THE FACTORY. DID THAT 6 MONTHS AGO AND IT SEEMED TO HELP EVEN THOUGH THE MANIFOLD THROTTLE BODY MOUNTING SURFACE WAS WARPED DUE TO THE ENGINE HEAT. OVER THE PAST MONTH THE CAR BECAME INCREASINGLY HARD TO START, BURNED LARGE AMOUNTS OF ANTIFREEZE, AND WOULD STALL INTERMITTENTLY. ON MARCH 13, 2008 I TOOK THE INTAKE MANIFOLD OFF THE ENGINE AND FOUND ANTIFREEZE IN THE INTAKE DUCT GOING TO THE AIR FILTER AND ANTIFREEZE POOLED IN THE INTAKE MANIFOLD. THIS WAS CAUSED BY TWO SEPARATE DEFECTS, THE UPPER INTAKE MANIFOLD GASKET NOT SEALING PROPERLY TO THE LOWER INTAKE MANIFOLD (WAS LEAKING IN TWO DIFFERENT SPOTS) AND THE LEAKING THROTTLE BODY TO INTAKE MANIFOLD GASKET (WAS LEAKING COOLANT INTO THE INTAKE DUCT TO AIR FILTER), WHICH WAS CAUSED BY EXCESS HEAT FROM THE EGR PIPE WARPING THE UPPER MANIFOLD. ANOTHER SERIOUS PROBLEM WITH THE UPPER INTAKE MANIFOLD WAS THE HEAT FROM THE EGR PIPE ERODED THE MANIFOLD TO A POINT THAT IT WOULD CAUSE LEAKING COOLANT TO…”