It is actually my room mate's latest car but I will be the one maintaining it.

As we know, all cars have common failure points or other quirks.
What might they be on a 2000 bonneville with the 3.8 engine?

The things I have already learned so far are -
The window motors seem to not work. Same for PDL.
The brake lines tend to rot out. In fact, I need to fix those before she can drive it safely.
On this particular Bonneville, it looks like stop leak was used in the radiator. I have no clue why. The radiator also seems to be mounted slightly diagonally. Is that normal or did someone do a botch job installing it?

Do these cars typically have any real nasty engine issues (similar to the 3400 overheating) or transmission issues?

What about little things?

I am just trying to prepare for what may come.

Some may have installed a new radiator and just didn't do a good job.

The lower intake gaskets and upper intake itself are the most common failure points on these vehicles. Lots of great reading to be found in this thread regarding all common problems with these cars:
2000-2005-other-than-gxp/topic25362.html

_________________
-Car Guy Carl
"Penelope" - 2003 SLE - 247k Miles
"Sydney" - 2000 Honda S2000 - 98k miles

I missed that one the first time. Just kind of getting acquainted with things. I appreciate being shown that thread.

That is quite a list. Things like "cups don't fit in cup holder" is not big but some of them are like...

I guess the hope is that by 170,000 miles, most of the important things that would fail already have and maybe fixed.
It does have door lock and window problems.

Note for the moderators or admins - so how long do new members stay on moderation? I was going to send a PM to the mods/admin but I could not find a button to do so.

thank you.

Hopefully a mod will see your question here regarding the PM, otherwise I can relay a message for you.

I would double check to see if it has the updated aluminum LIM gaskets. Easy to see, between the head and LIM you should see the silver gasket if it's been replaced. As far as the upper intake, I would just replace it anyways. It's less than $100 and an easy 1-2 hour job max with basic tools. Clean all of the throttle body sensors, do plugs and wires, change all the fluids... Note, don't flush the trans, just a filter and fluid exchange plus a TransGo shift kit will make it much happier. I'm guessing the front engine mount is worn out too. Once you do all of that and sort out the brakes and radiator, it should be a solid runner.

_________________
-Car Guy Carl
"Penelope" - 2003 SLE - 247k Miles
"Sydney" - 2000 Honda S2000 - 98k miles

Well it seems I am not on moderation now, I guess they just have to check a new user's first few posts to make sure it is not a spammer.

I will definitely be checking the intake gaskets.
The problem of course is I have NO history on this car. The trans fluid is red, the oil is black (but we have fresh oil ready to go) and the other fluids seem OK except brake. It needs new brake lines.

Does the UIM need to be changed on a regular basis? About a decade ago when i was on some other GM forum and there seemed to be a lot of issues with the 3800 series II intakes. If it does have the updated LIM gasket, would it be safe to assume the UIM is probably newer?

It's super likely that the power window issues are accompanied by non functioning power mirrors. If that's the case, the splice under the carpet behind the drivers seat has gotten wet and corroded. Indicator is green fuzz around the harness. It's a poor design by pontiac, almost like they didn't realize that the two tan bus wires needed to connect at some point for everything to work with the module properly.

Anyway, take all 4 of those tan wires back to good copper and splice in a new piece of wire to join them and water proof the connections and you should have your power accessories back up and running.

A couple of things that I've run into with my 2000 along the way at similar mileage now up to 200k..
blend door motor on the drivers side failed, causing no heat/cooling on that side of the dash ( not a difficult nor expensive fix if you do it yourself and buy your used parts through Andrew Suderman @ Bonnevilles Unlimited...he's our goto guy for everything Bonneville related. Super reasonable prices and quick to ship.

Sunroof drains if you have wet carpet in the cab and the trunk are due to the connections coming loose. The rears are easy, the fronts are a royal pain regardless of the method employed to get to them ( I had to tear my dash out for other reasons, so I did it the hard, but easiest to access and work with way ). Failed Dash lights are burned out bulbs soldered onto the gauge cluster. You can get replacement bulbs and fix it if you know how to solder. I did the upper and lower gaskets on mine when I first got it. Again, not a difficult job to do, just time consuming if you are the type to do things as best as you possibly can ( cleaning up the intake is a chore )

Common driveability issues usually stem from the MAF sensor and the Ignition control module, or individual coils, which is easy to figure out by swapping positions and seeing if the misfire follows the change.

Beyond that, I've had relatively few issues with this car for the age and mileage.

Oh, and if the fuel cap area hasn't started to rust, I would suggest spraying some fluid film in behind that area to prevent it.

_________________
A temporary fix does not exist. It becomes a solution until it needs to be fixed again.

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