coolant around upper plenum

dckelley

Member
75
5
8
i have coolant around upper plenum. I've posted about this car alot. car was given to me. i am not rich. i'm on ss and i'm not sure if fixing this anymore is a good idea. i was told by a cheap mechanic 500.00 to replace the upper plenum gasket. is there any other option? it's running and driving fine. stressed. Don.
 

Alan 55

Buick Newbie
162
57
28
Florida
Buick Ownership
2001 Buick Park Avenue, previously owned 1997 Park Avenue
Coolant around the plenum is not a good thing but I would suggest two other checks. Remove the oil filler cap and look at the inside of the cap. Hopefully you will not see a milky colored sludge or moisture. Next, remove your engine oil dipstick. Hopefully you will not see a milky sludge or moisture. Both checks should be done with the engine off. One more thing, use a sharpie to mark the exact level of coolant on your coolant reservoir. Keep a very close check to determine if you are loosing coolant. There are some other tests that are good also such as a cooling system pressure test but let’s start with the simple things first.
 

The Avenue

Full Member
116
5
18
Lafayette, IN
Buick Ownership
'01 PAU
How mechanically inclined are you? Like Alan is saying, check under the oil cap and check the oil dipstick for a milkshake sludge. You should also see it down in where you fill the oil, too. When my 01 Ultra was doing that, it turned out to be the intake gaskets. I would say start there. Not sure what year your PA is, but there should be a good how to on replacing them.
 

dckelley

Member
75
5
8
yep. thick whitish crude and when i tipped the cap water.
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The Avenue

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116
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Lafayette, IN
Buick Ownership
'01 PAU
I'd replace both gaskets. It's essentially not hard, jut a bit tedious on what you have to remove to get to them. If you have a buddy that's mechanically inclined, you might be able to buy him with pizza and a 24 pack of his choice. :p
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5.0MX5

New member
14
4
3
Buick Ownership
1998 Park Avenue, 2001 Park avenue
I'm 67, In the past year I've replace upper and lower intake gaskets on two different base (non-supercharged) PA's. One a 70,000 mile 2001 that's now totaled and it's replacement, a 1998 that I'm in the process of making a dependable cross country tourer out of. Both cars received (the 98 is still a work in progress) a lot more PM than gaskets, but that's the subject du jour.

If you have a shop or access to one or a attached carport along with a very few tools then intake gaskets are not hard. The first time I spend parts of two days working on the job. The second was a 1/2 day job to do both gaskets. Cost was less that $200 (without checking receipts)

One does need to be fairly mechanically inclined, or have a friend that is. Lots of online help if you decide to tackle this project. I'm sure I or others on this forum can help with any questions.

Good Luck,

Ron
 
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dckelley

Member
75
5
8
i know this is a no no with most mechanics but i used bars copper last night. i followed the directions to the letter and it seemed to help. i took it out on the highway today to get it nice and hot. i looked in the area it was leaking and it was dry when i got home. fyi i had sludge in the oil cap but not the dipstick. i don't think it is the head but a slow pinhole in the upper gasket. this car sat for a year or two before i got it. i wonder if the gasket had shrunk. i dunno we'll see how long this lasts
 

HotZ28

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1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
I think from the signs of coolant in the oil, you have an UIM, EGR internal tube burn through, very common problem on this model/year, if it has never been upgraded to the smaller pipe and sturdier UIM. We have many post about this failure, so do a search! If you have coolant sludge in the oil, the engine will not last long before total failure. You need to do a complete upgraded UIM replacement & EGR tube, not just patch the outside UIM leaking.
 

dckelley

Member
75
5
8
i don't have money to fix it so i hope it lasts until summer so i can walk where i need to go.
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HotZ28

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1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
Can you afford to change the oil/filter a few times to make it last a few more months? The new UIM replacement is not that expensive if you do it yourself!
 

dckelley

Member
75
5
8
could you give me a link that explains about the internal burn thorough in the egr hose? searched on here but i must be doing something wrong. sorry I'm just trying to understand
 
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dckelley

Member
75
5
8
"If you notice water droplets on the oil cap in addition to the milky residue, then most likely it's just condensation". this is what i have.
after a long drive it all burned away. the car runs great. all i can do for now is wait and see.. a bit of sludge on the cap. the dipstick oil is clean.
"However, if the oil on your dipstick looks like normal golden brown or dark brown oil and it’s at the proper level, then you don’t have coolant leaking into the crankcase." info i found elsewhere online.
update: no water in oil. under cap is dry. i'm going to fit in some longer drives with my in town driving. fix still holding. don't get me wrong this is the first place i come for input on my problems with this car. but for now when i can't afford or do the fix my hopes are up... oh and gas milage has gone way up. i dunno i'm happy :) running excellent.
 
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Ziggy

Full Member
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Buick Ownership
Buick Park Avenue 91 base
I would still do an oil change... when was the last one?
Pull the dipstick out, and hold a lighter flame at the bottom end. If there is any sizzling or sputtering when burning it is mixed with coolant...
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dckelley

Member
75
5
8
I would still do an oil change... when was the last one?
Pull the dipstick out, and hold a lighter flame at the bottom end. If there is any sizzling or sputtering when burning it is mixed with coolant...
about a month ago it looks super clean. but i think i will take your advice
 

dckelley

Member
75
5
8
i will more than likely have it done right she needs the valve covers done too. my fear with fixing it right/ fixing everything I've had fixed something catastrophic will happen and all my money will be lost.
Can you afford to change the oil/filter a few times to make it last a few more months? The new UIM replacement is not that expensive if you do it yourself!
i just watched a video of a guy pulling the upper plenum. he had it off in 10 minutes. he showed where the egr burns through. maybe i could do it. i've just never messed with a fuel rail before..
 
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