Comments: 1-15, 16-30, 31-45, 46
It seems to need brake maintenance more often than should be necessary.
Paint on the hood and roof cracked at 60000 miles.
Right window will not seal while at highway speeds resulting in wind noise.
Plenum cracked at 99000 miles and trashed the engine resulting in a $1500 cost. GM apparently knows about the problem, but refuses to acknowledge it.
Fan speed switch started working intermittently at 80000 miles.
Extremely comfortable to drive, very good ergonomics for a large man. I'm 6'3" at 260 lbs.
Smooth handling and ride with good cornering, but a little slow in the initial acceleration department.
I bought this vehicle loaded to the point where the only thing different between it and the SLE is leather seats and I would consider it a pleasure to own had GM not dropped the ball with the defective clear coat and the inclusion of a plastic plenum sandwiched in between the steel intake manifold and block. As a engineer, I can see the simplicity of this error and am dismayed by GM's indifference to it.
Right on. I had a 1998 SSE and had the same problem with the plenum cracking at 74,000 miles!! That was in May 2003 and I am just learning what a major problem this is on these cars. How about a class action law suit against GM. Obviously they know about this defect and refuse to recall because it will cost them a fortune.
I'm in on any lawsuit. Mine blew up at 68K miles.
And the trans needed to be rebuilt at 63K miles.
I also have a 1998 Pontiac Bonneville SE, The plenuim cracked on mine at 81,000 miles. This resulted in a long period of time without being able to drive it due to the cost to repair it. I do agree the brakes go bad quickly.
The aforementioned comments are very distressing. Our plenum cracked at 70,000 and we have just had it towed after only a year on the new install. It appears to be the exact same problem, but the plenum only lasted about 12-15,000 miles this time. We are hoping to get GM's attention, but it doesn't look good from the previous comments. I love this vehicle otherwise and hate to be forced to sell it. A class action might be appropriate.
Just had the same problem. I only had the car 2 days. 73K miles and the dealer was happy it didn't happen before they sold it. They said it was without warranty on all used cars. I was hopeful the new Plenum would be better, but the last posts put an end to that hope. I'm in for a class action. This is on a 99 Buick LeSabre. 3.8L K engine. I like the way the car drives. It may be time to move on to a Lincon.
Doug.
I have a 1999 Bonneville and had the same problem with the intake plenum cracking. I am not happy about this considering I had to pay $900 to get it fixed. I would like GM to acknowledge this problem and send out a recall and reimburse the people that have had to put out the money to fix this problem. It's obviously a factory issue since its very common on these models.
I also have a 1999 Bonneville and had the same problem with the intake plenum cracking. The car had 77,000 miles. After $2200.00 I have a 2000 engine in my car. I also would like GM to acknowledge this problem and send out a recall and reimburse the people that have had to put out the money to fix this problem. Plastic parts on and engine? Poor engineering GM.
Today I had the same experience with my 98 Bonneville. The repair shop knew the problem even before I had them tow it to the shop. All I told them was the year and model of the car. They told me the problem before I even told them the problem. Hmm, almost seems like this is a common problem huh? The shop gouged me 300 in parts and 450 in labor for what looks like a simple replacement by the book and the parts are available on the web for about 130. It looks like I will either become an expert in plenum replacement or invest in the MOTOR Parts and Time Guide.
I've owned my '98 Bonneville for six months. Bought it with 89,000 miles. Guess what my first problem is at 101,000? Yep a cracked plenum. I was disappointed at the cost of parts as well as the repair. I checked for recalls at my nearest GM dealer and the only recall that showed up was for the fuel pressure regulator. That is my next fix. Check with your dealer for this recall! I still love my Bonneville! Best car I've owned so far... except for my costly plastic manifold problem.
I haven't had the plenum problem, or any of the problems mentioned so far, but since the plenum problem seems so common, I looked into it. There is a repair kit apparently available, "Upper Plenum and Lower Intake Repair Kit", that comes with a reinforcing sleeve, and other parts, that is supposed to correct the problem. My car has 170k, no paint issues, or any issues, accept for typical maintenance items.
OK, this is cool to see others talking about this.. I just turned 89K miles and man I have to say I am happy that my problem maybe the simple plenum. My thoughts were geared to maybe the head gaskets. I would have gave up on the car at if it was. But the plenum isn't all that bad when you compare the 2 jobs. I was quoted a price of $500 parts and labor. I am sure that is my problem now, I can see where it warped at the intake side. I too seen the plenum parts online for $130 and it is suppose to be improved. Dealer wants $180 with all the associated o-rings and tubes. Now I like doing my own work, anyone do this job themselves yet? Where is this hidden bolt? Any tips? I guess I will pick up a manual.. GM should give a warning at the least.. if you have this problem you should not drive the car till fixed, it can hydro lock if enough coolant is in the cylinder causing permanent engine failure. As far as brakes, I had problems with the gm rotors.. I spent $200 on a set of power slot brand rotors and problem was solved.. I don't mind changing pads, they are easy and reasonably cheap, but new rotors every brake job will put a drain on the pocket. Well I hope you all get what you want.. I love the car, good mpg, looks good, seats 6 and was always dependable.
Short & sweet (or sour depending on your view) and to the point - 99 Bonneville, 75,000 miles, warped plenum, hydro locked engine - $850 repair.
I have a 1998 oldsmobile eighty eight with the 3.8 engine. At 65,000 miles the coolent started to leak from the throttle body area into the intake manifold. I bought a new upper intake from E bay for 115 dollars. Replaced it myself. Now the car is running good...5 degrees cooler and much more power than before. The two bolts that are hidden are just underneath the upper intake manifold. They hold the lower intake manifold in place. The new upper intake manifold had cheaper plastic threading which attaches to the throttle body. The original upper intake had steel threading. I did the total job in about 7 hours. I had experience in doing this job before with a 1997 LSS.
98' SE cracked intake manifold, and water logged engine. You can get after market manifold that won't melt and fix the problem. $1500.00 repair.
I had the same problem on my wife's 1998 Pontiac Bonneville, i.e., "upper plenum cracked causing coolant to intermix with oil", which resulted in a $830 repair bill. I bought the car used in 2004 and it had 79k miles on it when the problem occurred. Comments by my local mechanic and the service manager at the Pontiac dealer where I purchased the car
indicate that this is a very common failure. Apparently Pontiac / GM is aware of the defective design, but refuses to acknowledge responsibility.
BC from Pennsylvania.