Coolant around upper plenum

Tiny
DCKELLEY
  • MEMBER
  • 1998 BUICK PARK AVENUE
  • 3.8L
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 190,000 MILES
I have coolant around upper plenum. I've posted about this car a lot. Car was given to me. I am not rich. I'm on Social Security 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.
Friday, March 15th, 2019 AT 2:37 PM

8 Replies

Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello,

If the coolant isn't getting in the spark plug holes, or messing with any sensors or such, I guess it would be okay to drive like that as long as you kept I real good eye on your coolant level and Kept it filled up. Eventually the gasket will degrade enough that it will require replacement. In the diagrams below I have included step by step directions on how to replace it yourself if you wanted to. I also have sent along parts price and labor estimate for you if you decide to shop around to have a shop replace it for you. Either way, please get back to us with what's going on.

Thanks,
Alex
2CarPros
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Friday, March 15th, 2019 AT 3:05 PM
Tiny
DCKELLEY
  • MEMBER
  • 125 POSTS
What do you think of trying bars? I bought the one with liquid copper. Worth a try. I only drive to the store and doctor.
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Friday, March 15th, 2019 AT 3:21 PM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

My personal opinion about that stuff is I don't like it. The reason I don't like it, though, is because I would rather fix things they way they were when before they failed. That's just me though. Bars might work, might not. If you were going to go that route, might I suggest a product that's a little more expensive, but has a lot better track record. It's called Blue Devil. You might want to check it out at your local part's house.

Thanks,
Alex
2CarPros
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Friday, March 15th, 2019 AT 4:43 PM
Tiny
DCKELLEY
  • MEMBER
  • 125 POSTS
Can I use blue devil after the bars? I've used the bars. Maybe I'll wait for a bit. If it doesn't work, then blue devil. I understand completely about fixing instead of additives and I figured I'd hear that. But I can't afford to do it. It's that simple. I can't do the things I used to be able to do or maybe i'd try fixing myself.
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Friday, March 15th, 2019 AT 5:45 PM
Tiny
DCKELLEY
  • MEMBER
  • 125 POSTS
I checked my oil and I have creamy whitish slug in the cap.
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Friday, March 15th, 2019 AT 6:15 PM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello,

That usually is a sign of a blown head gasket, although some cars will allow coolant to get mixed with oil via the ports in an intake manifold. If you are not going to change the gasket I would recommend putting in Blue Devil. If you do, please follow the instructions to a "T". I've heard of and seen the stuff really work, and for a long time as well. Get back to us and let us know what's going on.

Thanks,
Alex
2CarPros
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Friday, March 15th, 2019 AT 11:11 PM
Tiny
DCKELLEY
  • MEMBER
  • 125 POSTS
There was no water on the dipstick or white slug. I read that short trips can cause some moisture and a bit of that slug on the cap. Before the blue devil was recommended I used bars. I'll drive it for a few days and see what happens. Thanks, Don
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Saturday, March 16th, 2019 AT 12:56 AM
Tiny
DCKELLEY
  • MEMBER
  • 125 POSTS
After using 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. No water today. 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.
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Saturday, March 16th, 2019 AT 1:36 PM

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