Mysteriously wet intake tube. (?) And vacuum leak?

Yup, sorry! New Plenum (UIM) and gasket (Dorman), new aluminum coolant elbows. New pcv valve and O-rings. New injector O-rings, cleaned the injectors up. I lubed all the O-rings to make sure none of them rolled on me. I used a mirror to inspect the elbows to be sure those seated properly. I used the universal prestone, I think it's yellow to lube the elbows. That seems to work pretty well for me.

I know lots of people recommend the ATP parts, but I am crossing my fingers with the dorman parts. I used AC-Delco OEM (Gold) sparkies and sparky wires.
I already have a big tube of Permatex Dielectric Grease - 22058, so I never need to buy that.
I did a thorough flush of the coolant seven years ago, getting rid of the dex-cool and going with prestone universal (yellow)
 
I tried to upload a photo, but I can't figure out how to do that. It shows a uniform coating of coolant covering the rubber intake tube, as if it condensed on the surface. Throttle body and air intake box all perfectly dry and clean. This year I found pools of coolant. Last year (when I started this post) there was no coolant to be seen anywhere except the rubber intake tube. And the coating on the intake tube was much more subtle.
 
gasket (Dorman), new aluminum coolant elbows. I lubed all the O-rings to make sure none of them rolled on me.

I already have a big tube of Permatex Dielectric Grease - 22058, so I never need to buy that.
1) were your gaskets metal framed and not plastic?
2) did you use ac delco o rings with dorman elbows, or ac delco aluminum elbows
3) WHAT EXACTLY DID YOU LUBE THOSE O RINGS WITH?
4) same reason as #4, you mentioned you did a tune up but im just looking to understand what exactly you used it on and how did you apply the grease to the boots for the plugs?
5) so you used 41-101 for your plugs?
 
I tried to upload a photo, but I can't figure out how to do that. It shows a uniform coating of coolant covering the rubber intake tube, as if it condensed on the surface. Throttle body and air intake box all perfectly dry and clean. This year I found pools of coolant. Last year (when I started this post) there was no coolant to be seen anywhere except the rubber intake tube. And the coating on the intake tube was much more subtle.
1) I used FEL-PRO MS98014T for the lower intake gaskets, they are the metal re-designed. The kit included the black rtv, but I pitched that and used Permatex 82180 Ultra Black

2) I used Dorman metal coolant elbows (DORMAN 47065HP) with the O-rings that came on them. Based on how they installed, I would NOT, NOT, NOT recommend them. I should have spent a little more and got AC Delco. The ones I installed (Dorman) did not fit well. They were TOO TIGHT. If I ever have to redo them, I'm going for the AC Delco for sure. I lubed the elbow parts (the inside of the tensioner ports, and the elbows with coolant (the prestone universal yellow). That part worked out well. The elbows would have been too tight regardless of whatever I used for lube.

3) I cleaned the fuel injectors (the business ends) with brake cleaner, then for lubing the rest of the O-rings (injectors, pcv valve, MAP, brake vacuum hose) I used SIL-GLYDE brake lube.
not gobs, just enough to do the job. ,

4) I used Permatex Dialectric on the sparky boots. I put a pea-sized little gob inside the boot at the very opening, then I took a small screwdriver and spread the dielectric grease around and around the inside of the boot to just the first 1/4" or so, of the inside of the boot. Being careful to not push it near the metal connector.

5) I used ACDELCO 41-101 (Iridium), for the sparkies. And the sparky-wires - ACDELCO 9746DD (Standard Replacement) Gold
 
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1) I used FEL-PRO MS98014T for the lower intake gaskets, they are the metal re-designed. The kit included the black rtv, but I pitched that and used Permatex 82180 Ultra Black

2) I used Dorman metal coolant elbows (DORMAN 47065HP) with the O-rings that came on them. Based on how they installed, I would NOT, NOT, NOT recommend them. I should have spent a little more and got AC Delco. The ones I installed (Dorman) did not fit well. They were TOO TIGHT. If I ever have to redo them, I'm going for the AC Delco for sure. I lubed the elbow parts (the inside of the tensioner ports, and the elbows with coolant (the prestone universal yellow). That part worked out well. The elbows would have been too tight regardless of whatever I used for lube.

3) I cleaned the fuel injectors (the business ends) with brake cleaner, then for lubing the rest of the O-rings (injectors, pcv valve, MAP, brake vacuum hose) I used SIL-GLYDE brake lube.
not gobs, just enough to do the job. ,

4) I used Permatex Dialectric on the sparky boots. I put a pea-sized little gob inside the boot at the very opening, then I took a small screwdriver and spread the dielectric grease around and around the inside of the boot to just the first 1/4" or so, of the inside of the boot. Being careful to not push it near the metal connector.

5) I used ACDELCO 41-101 (Iridium), for the sparkies. And the sparky-wires - ACDELCO 9746DD (Standard Replacement) Gold
EVERYTHING good except the silicone on the o rings for the fuel injectors
Might want to redo. Use engine oil
 
1) I used FEL-PRO MS98014T for the lower intake gaskets, they are the metal re-designed. The kit included the black rtv, but I pitched that and used Permatex 82180 Ultra Black

2) I used Dorman metal coolant elbows (DORMAN 47065HP) with the O-rings that came on them. Based on how they installed, I would NOT, NOT, NOT recommend them. I should have spent a little more and got AC Delco. The ones I installed (Dorman) did not fit well. They were TOO TIGHT. If I ever have to redo them, I'm going for the AC Delco for sure. I lubed the elbow parts (the inside of the tensioner ports, and the elbows with coolant (the prestone universal yellow). That part worked out well. The elbows would have been too tight regardless of whatever I used for lube.

3) I cleaned the fuel injectors (the business ends) with brake cleaner, then for lubing the rest of the O-rings (injectors, pcv valve, MAP, brake vacuum hose) I used SIL-GLYDE brake lube.
not gobs, just enough to do the job. ,

4) I used Permatex Dialectric on the sparky boots. I put a pea-sized little gob inside the boot at the very opening, then I took a small screwdriver and spread the dielectric grease around and around the inside of the boot to just the first 1/4" or so, of the inside of the boot. Being careful to not push it near the metal connector.

5) I used ACDELCO 41-101 (Iridium), for the sparkies. And the sparky-wires - ACDELCO 9746DD (Standard Replacement) Gold
I also don’t recommend permatex black for coolant contact. Permatex blue or right stuff (black/red) would be better. How long did you let it cure? I wouldn’t redo the job solely for the elbow o rings or the rtv, though
 
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I also don’t recommend permatex black for coolant contact. Permatex blue or right stuff (black/red) would be better. How long did you let it cure? I wouldn’t redo the job solely for the elbow o rings or the rtv, though
I used the Black Ultra rtv to dab in the corners where the lower intake gaskets meet (as per the instructions). So it's actually underneath the LIM where it would be in contact with the engine oil. I let it cure for a couple of days. We finally had some warm weather that would be conducive for the curing of the rtv. For rtv that's in contact with coolant, I've used Permatex 22071 Water Pump and Thermostat RTV Silicone Gasket in the past. I didn't use any of that for this job. I didn't apply any rtv around the coolant ports at all. I've seen in videos where some people do.
 
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I used the Black Ultra rtv to dab in the corners where the lower intake gaskets meet (as per the instructions). So it's actually underneath the LIM where it would be in contact with the engine oil. I let it cure for a couple of days. We finally had some warm weather that would be conducive for the curing of the rtv. For rtv that's in contact with coolant, I've used Permatex 22071 Water Pump and Thermostat RTV Silicone Gasket in the past. I didn't use any of that for this job. I didn't apply any rtv around the coolant ports at all. I've seen in videos where some people do.
The gasket is doing its job for those. Good thing you didn’t. I’m glad you used the rtv in a good spot and gave it 24+ hours. Excellent. I don’t know if silicone will hurt those o rings but the primary issue with using them on the fuel injectors is that silicone will poison your o2 sensor especially if it migrates. If you remove the injectors and the o rings are okay just clean them well with a degreaser wipe and then dip some clean engine oil and lube. Maybe use q tips and carb cleaner to clean the ports.

Not sure how much silicone poisoning it can cause but the long term nature of the migration makes me say all this.
 
I used the Black Ultra rtv to dab in the corners where the lower intake gaskets meet (as per the instructions). So it's actually underneath the LIM where it would be in contact with the engine oil. I let it cure for a couple of days. We finally had some warm weather that would be conducive for the curing of the rtv.

The gasket is doing its job for those. Good thing you didn’t. I’m glad you used the rtv in a good spot and gave it 24+ hours. Excellent. I don’t know if silicone will hurt those o rings but the primary issue with using them on the fuel injectors is that silicone will poison your o2 sensor especially if it migrates. If you remove the injectors and the o rings are okay just clean them well with a degreaser wipe and then dip some clean engine oil and lube. Maybe use q tips and carb cleaner to clean the ports.

Not sure how much silicone poisoning it can cause but the long term nature of the migration makes me say all this.
Ah!! that's good to know (about the silicone killing O2 sensors.) I did not know that.
About the rtv being applied to the upper intake gaskets, the GM service manual is quite adamant about NOT using any rtv for that. I really wanted to! But decided against it. I figure they wrote the manual, so they should know. Too bad I didn't read the manual about lubing the fuel injectors.
 
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I did end up pulling the fuel injectors out and cleaning the Syl-Glyde off the injectors. I had brand new O-rings, so I just went ahead and replaced with new. Cleaned the fuel injector ports out as well, just as good as I could. I # recommend not ever using Syl-Glyde on anything but brakes. I didn't think I had used very much, but it really was quite a mess. I used a little motor oil instead this time.

Coolant had leaked into cylinder #6 through the fuel injector port. I could see the residual trail of coolant (I had put in some dye) leading there. I was very lucky that I didn't hydro-lock cylinder 6. I should have pulled the spark plug and siphoned out the cylinder. I just started it like a ninny. A huge cloud of white came shooting out the back, and judging by the output of O2 sensor #2 it poisoned the catalytic converter.

My '04 Lesabre has 210k miles on it now, so I decided to just go ahead and replace the original cat, resonator pipe, muffler and both o2 sensors. This stuff was all original anyway. RA has the cat on clearance for $100 right now.

I didn't see any evidence of silicone poisoning on the o2 sensors, but I'm glad I cleaned the Syl-Glyde off the injectors to minimize any chance of that in the future.

If there's any moral to this whole thread, it is this: If I start losing coolant again, and there's a hint that it could be near the intake, I will just go ahead and pull the plenum off and check it out and change the plenum gasket. Postponing the repair ended up just costing me more in the long run.
 
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After heating up the car, the moisture disappeared from the intake tube.

And I looked around tonight for the coolant leak. (I put in the dye a couple weeks ago) still no signs of where it's going.
Hi I have been lurking since I bought my new-to-me 'beater with a heater' 2004 LeSabre
This moisture you saw on the intake tube peaked my interest.

My car was laid-up in my daughter's garage for a couple of years. I had taken the intake tube and filter cover apart to get to the brake lines. The rubber was very stiff and difficult to separate. But I had sprayed a lanolin-based corrosion protection (Fluid Film) on some rusted areas, including the filter box clips.

When I got back to the car, the intake tube was dripping wet inside and I was frustrated that I would have to get it cleaned out so it didn't contaminate the MAF sensor when I got it running.

Again, after some delay, I found that the 'rain' was gone, and the rubber tube was much more pliable when I put it back together. The engine never ran for those 2 yrs.

Now (a year or more later) the tube is hardening again, but also deteriorating -- greasy, sticky, with particles coming off when handled. These are symptoms of the lanolin contamination from the overspray.

I expect to replace the tube when I get a spare $30-$40 bucks

I just have to wonder if you are having a similar experience?

Jim A.
 
No, not at all. The "greasy sticky" mess the intake tube was covered in was like a mist of what turned out to be coolant. I took the rubber intake tube off, took the air intake temperature sensor out and then sprayed it with brake cleaner, (as I recall) cleaned it off with a rag inside and out. The tube was as good as new. I haven't had any of the problems you are describing, except that the tube IS stiff. You do have to wrestle with it a little bit to remove it, and install it but I think that's normal - you wouldn't want it to fall off accidently, right?

I guess I would try to clean it off with brake cleaner and see if that helps. If not, maybe you could source one on ebay or salvage yard.
 
No, not at all. The "greasy sticky" mess the intake tube was covered in was like a mist of what turned out to be coolant. I took the rubber intake tube off, took the air intake temperature sensor out and then sprayed it with brake cleaner, (as I recall) cleaned it off with a rag inside and out. The tube was as good as new. I haven't had any of the problems you are describing, except that the tube IS stiff. You do have to wrestle with it a little bit to remove it, and install it but I think that's normal - you wouldn't want it to fall off accidently, right?

I guess I would try to clean it off with brake cleaner and see if that helps. If not, maybe you could source one on ebay or salvage yard.
Thanks for the response.
And yes, I am searching.
It is a shame we can't get certain parts (discontinued). I would like new (doors) window seals - old ones won't be any better.
 
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