What Would You Do? Silhouette Intake gasket

The gasket repalcement for my car was a hard composite like material with rubber seals around the holes where coolant passes throught. So yes I guess there could be a burn't plastic odor.

The odor might of been hot anitfreeze around the top of the engine. Have the dealer inspect the intake manifold for any damage too.

Aside from the intake / & gasket problems that have plague the 3400 /

3800 engines they are very reliable workhorses.

If you feel uncomfortable with the deal don't buy the vehicle or ask about an extended warranty.

good luck .

========= Harryface =========

1991 Pontiac Bonneville LE, 3800 V6 _~_~_~_~276,100 miles_~_~_ ~_~_

"Gini" wrote

This is a common problem with these vans. But if the intake manifold gasket is replaced properly, and not a lot of coolant was getting "into" the engine, you will probably have good service out of the engine. At that low mileage, and your description of the smell, I'd say that you probably had more of an "external" coolant leak.

Ian

==== Thanks Harry Face and Ian (I have a son named Ian)! I did some research (found vmag forum--what a great site) and from that and what you two have said, I guess the van is a better deal since the problematic gasket is being replaced now and not after the the warranty runs out in June. I wish the dealer would have told me that's why they are backordered. I am going to talk to the head mechanic tomorrow and level with him about the gasket problems and ask him to be sure to check other things that might be related to the gasket failure. I'm thinking since the gasket is plastic and plastic is what we smelled, that it probably just went on that test drive--maybe since it was so darn cold? (I know the smell wasn't coolant as I've had more than my share of coolant leaks with the Audi and became

*real* familiar with that odor.) I will go ahead with the van deal but will definately get an extended warranty and I hope I do not become as familiar with Silhouette problems as I am with Audi problems ;-(. Thanks again, guys! == == >

The dealers are well aware of the problem as the 3400 will not go much more than 40 k without blowing the gasket. He had to be aware of it if it was leaking to a point of you smelling it. If it has been leaking for some time and getting in the oil serious damage could be done to the engine. This problem happens to an high number of these engines and GM will not pick up any of the charges. I went thru it with my 99 Venture. All of my cars have been GM but the Venture was the last due to their support. I only had 36k on the Venture.

== How would I know if there is engine damage--What are the symptoms and when do they surface? What I'm asking is whether damage would be obvious or take some time to be apparent. Wouldn't an extended GM warranty cover subsequental problems, if any? Thanks for your input. == ==

"Gini" wrote

In the case of the vehicle that you are looking at, it would probably surface later in it's life. A lot depends on how much coolant and for how long....has been going into the oil. A sure sign of dexcool being in the oil for a period of time is a dark brown sludge that coats the internal surfaces of the engine. Here is a picture of an intake manifold and valve covers from an affected engine. You can see the dark brown areas.

The main type of damage that I've seen (which is very rare on low mileage engines) is the camshaft snapping in two. What appears to happen is that eventually there is loss of proper lubrication at the camshaft journals, the cam siezes in the bearings (usually the rear bearings) and the front half of the camshaft is broken from the rear of the camshaft. Kinda like this:

Anyway, this is all worst case scenario stuff. I doubt that you will have any problems if you simply stick to a 3,000 miles/

3 month oil change interval and always keep an eye on engine coolant levels. Do not listen to people that tell you that you can run extended oil change intervals...even if you were to use synthetic oil. Nothing will counteract the effects of coolant in oil like simply "changing the oil" at a reasonable interval.

Yes, and a GMPP plan is by far the best plan available. It's a company that you know will be around, and there is almost zero authorization hassles with GMPP. Make sure you read the fine print though, and get a good plan that actually covers most of the items on the vehicle.

Ian

Well, my 2000 Montana just back with the famous gasket problem. Bad news is that I knew about this famous problem AFTER I got it fixed.

Anyhow, the dealer paid half of the cost including labour in the end, I didn't ask why and they didn't tell me. At first, I thought it must be some sort of mistake but now I know why. I've been with the same dealer since 94 with our Regal and now the Montana, I don't think they'd rip me off. Generally, I'm happy with their service.

I don't know much about cars other than checking out all fluids and changing oil at most, every 4 months or tops 6000km. I first noticed the problem in the fall when the temperature gauge went all the way up pretty close to RED when idle or stuck in stop and go traffic. I brought the car in and they didn't know where the problem was. Ever since I've been closely checking the coolant level and I was losing a bit over the last few months but nothing much. I had a problem with "Coolant Low" warning and they replaced the sensor but that didn't work. One time I brought it in while the warning was still on, a technician took out the coolant cap while the engine was running and did something, then the warning disappeared for good. Not sure if he did the right thing though.

Finally, just after Christmas of 2003, we noticed the garage floor had some kind of fluid with a bit of pink colour. The service advisor told me from the dealer it was the coolant leaking. Great, then she told me what happened and what needed to be replaced. The van has been driven gentlely and only 45000km on it so far. I can't believe I had to shell out over $1100 for the repair.

I hope there's nothing damage to the engine but I'll keep an eye on the brownish stuff.

I like reading this forum as I'm learning a lot everyday.

Thanks,

Simon

== Thanks, Ian. Will stay on top of oil changes and mark the coolant level on the overflow container so it's easier to watch. Do you see any merit in using Mobile1? Do you have any opinions on Marvel Mystery Oil additive? Many of the guys on the AudiWorld forums swear by it but I'm not sure why.

The GM dealer left a message on my answering machine today that the gasket is confirmed enroute so I will likely be taking possession by Friday. I will probably go with the 84/70 Major Guard warranty. Since the van will be payment free, I'd like to run it as long as possible and that's the longest I can get the GMPP for it. I'm sure the time will be up before the miles though. Thanks again! == ==

"Gini" wrote

I think that Mobil 1 is a good oil. I don't use it and never have, but that's probably because I tend to change the oil in my "good" cars even more often then every 3000 miles. So I figure that regular oil will be sufficient. I've never had an engine failure that was oil related yet anyway.

I have no real experience at all with the Marvel Mystery Oil on cars, but I have used it as a great after-run oil in my radio control model airplane engines. I'm always leery about additives in general. I suspect that the majority of them simply have a "placebo" type effect on the users. Often, what you "think" a particular item does can be more important then what the item "actually" does.

No problem, and congratulations on a fine choice of name for your son. (grin) Some Scottish background in your family?

Ian

Well, that's half of the problem. I'd use normal oil and change these engines every 3000-4000km. No joke. The regular oil should be as heavy as prudent as well, so that less of it seeps through. Ultra-thin synthetic is going to get by those seals a bit faster.

Definately get the maximum warranty that you can with a GM car, because the first major repair will cost you $1000-$2000 easily.

I would walk on this van deal myself. Some day you will thank me ;-)

..........................................................

== Kinda :-) --We're descendents of English shipbuilders and German outlaws. I first heard the name in my high school years (long, long ago) in PA. ==

LOL--You might be right, but, it sure is a purrrdy van. After all, isn't that what *really* matters? (And, it *can't* be worse than the Audi--Can it??) == ==

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== Was that due to the loss of coolant? I've decided to get the max warranty available from GM so I'll be covered for 4 years/70k, anyway. ==

Well, the temperature problem wasn't related to the low coolant because I only topped up maybe 100ml and the tank wasn't empty. However, whatever they did fixed the problem. The bill showed a few things though other the gasket and who knows, it could be the thermostat.

Hopefully everything is fine when the summer comes, thanks.

Simon