Last post on Jan 25, 2013 at 11:52 AM
You are in the Pontiac Bonneville
What is this discussion about?
Pontiac Bonneville, Sedan
#973 of 2268 2000 Pontiac Bonneville Intake coolant leak
Jan 28, 2003 (10:01 am)
I own a 2000 Pontiac Bonneville SE with 54000 miles on it . This past week I have developed a coolant leak somewhere on the drivers side of the car , under the throttle body. I cannot see exactly where the leak is coming from , and it seems to happen mostly the first time I run the car for the day . After that the leak seems to diminish. I have been told from a dealer that it is probably an intake manifold leak , either at the base of the plenum, or where the throttle body bolts up to the plenum/manifold. This looks like a major design flaw to me , and was wondering if there is anything going on , from GM to remedy this problem.Please send me an e-mail if anyone has had the same problem with this year or newer car.Thanks ,Bill
#974 of 2268 Intake problems.
Jan 28, 2003 (10:26 am)
My wife's 2001 Grand Prix was just repaired. The leak was coming from the upper plenum on the intake. Never noticed until warming up the car one day. Coolant was left on the driveway. Was told that it leaks generally when cold. Due to the location, there was no oil contamination. Changed oil anyway. Car serviced at 28K. My 2001 Bonneville with 21K has the same problem. Need to get it in for warranty service. I definitely am concerned that this will happen again in 20K or so.
Jan 28, 2003 (9:18 pm)
I have a 2002 SE. I have been reading the horror stories on this board and others about the design flaw of the intake manifold being made out of plastic and eventually leaking and in some cases getting into the engine and causing major damage! Does the 02's inherent this problem? I would have never bought the car if thats whats in store.. You would think Pontiac would have taken care of this problem by now.. Concerned in NY
#976 of 2268 Intake Manifold Leaking
Jan 29, 2003 (7:15 am)
I got my '02 SLE with just 17000mls back from the dealer yesterday fixing it. I'm also wondering whether this a fix for good or just for the next 17000mls... :^(
Does anybody know if the part # changed for the good part, if it exists? The part # of the replacement was 17113136.
I've also noticed that the gasket (part # 17113137) was not itemized in the replaced parts list. Shouldn't it have been? I asked the service guy and he told me that 17113136 is probably a kit that includes the gasket...
Does anybody have a TSB about this issue?
#977 of 2268 Leaking intake manifold
Jan 30, 2003 (12:57 pm)
Good news for me , I discovered that the gasket between the manifold and the throttle body was bad. The gasket was 14 bucks and I fixed it myself last night. The only thing I am worried about is that the dealer said that entrapped air in my cooling system could damage the under side of the intake manifold. I bled all the air out of the top of the thermostat housing bleeder, and hope that this will be enough. At least it wasn't the whole manifold job. I will keep my fingers crossed as to when the hammer will fall on this part. Does anyone know of a surefire way to ensure that all of the air is out of the system.
I hope this solves this one for me . It only took about an hour or so to repair. Thanks , Bill
#978 of 2268 Re: Intake Manifold Leaking
Jan 30, 2003 (1:23 pm)
FWIW, the only TSB about this doesn't apply to the current engines. As you can see here, the TSB recommends replacing the lower intake manifold as well. However, the current engine has a different one that supposedly fixes the issue, as you can see here.
I did confirm with the service assistant that the upper manifold # 17113136 does include the gaskets between it and the lower manifold and between it and the throttle body.
What gives me the creeps is that, unless the original part was from a bad lot, just replacing the upper manifold doesn't address the issue... I was lucky that this time the coolant leaked outside the engine, for had it been inside we'd be talking about a potentially severe engine damage. :^(
#979 of 2268 Upper intake / plenum leak
Feb 07, 2003 (7:28 pm)
Just had this problem repaired with mine as well....approx. $250. 2000 Bonneville SLE with 50,000 miles. Get it fixed quickly to avoid leakage internally. Ironically 2 days later I notice small noise in steering column when turning left at slow speeds. I've read about others with this problem and a tech bulletin has been issued on this. Inexpensive piece in steering shaft replaced and some lubrication....$140. These are the first items I've had to spend money on since purchasing the car new. Overall quite satisfied with the "new" Bonneville look and ride but I expect not to see the Service Dept. for quite awhile.
#980 of 2268 Plenum Fiasco!
Feb 10, 2003 (8:12 pm)
Finally replaced the plenum on my 98 Bonneville with 128,000 miles. I know the problem started a long time ago but for many reasons I just kept adding more Dex-Cool. A family member who teaches auto mechanics helped me do the job saving me alot of money. Depending on what mechanic you ask some say the Dex-cool is the real culprit with this problem others say the gasket material was insufficient for the job. The ironic part is that the Dex-cool does less harm to the engine if it gets in than regular anti freeze would. There was a large amount of sludge in the plenum and the next piece under it, so we had to remove and clean that also and replace the 3 gaskets for it. We did computer testing on the motor after the job and there doesn't appear to be any damage done to the motor from having the Dex-cool invasion. Bottom line for me on this issue is GM needs to get sore ears from complaints about this. The parts guy at the dealership we bought our kit from said they just received a shipment of about 60 units, and that they did 2-3 Plenum jobs a day. That's at one dealership!!!!! They need to admit the problem and step up to the plate and do a recall.
Feb 10, 2003 (9:33 pm)
Dex-Cool can't be the problem because 1995 3.8s may suffer the degradation and Dex-Cool wasn't introduced until 1996. Its not gasket problem either because the gaskets do not leak on the manifolds with the degradation (95-98). (But the gasket can leak on a 2000-2001, although some dealers appear to be replacing the upper manifold also.) And you never hear of the problem in the Grand Prix which also used the 3800 Series II (I can't recall ever seeing a post in the Grand Prix threads here at Edmunds or the Grand Prix Sites). SO it appears that some combination of factors that occurs in some cars causes the failure. And as a non-safety issue it would be unlikly that a recall would ever happen.
But the $550 you spent for the two manifolds and the gasket will keep you car going for a long time hopefully.
#982 of 2268 Plenum Problems - 1999 ?? (montanafan)
Feb 10, 2003 (10:17 pm)
It seems like the one year you didn't include in your post was 1999. I have a '99 SE. Is this year also susceptible to the plenum problem? I have about 65k miles on it, w/ no problems so far. Crossing my fingers...