Buick 3800 V6 intake leaks and what causes it

[@smirkinatu5512]

Thank you for recording and posting this educational video.

[@bikelyfe9052]

Convert to a series 3 aluminum upper intake that's what I'm looking into doing on my 03 Pontiac bonneville sle she's almost at 300k original engine and transmission but I've done the lower and upper intake 2xs already and how you explained it makes sense why the plastic wears out

[@matthewbrown770]

Why couldnt this video pop up in the algarithm months ago. Only other comment is that a replacememt is 59 dollars. Good day sir! Thanks

[@anthonyhfe6450]

Yes, good analysis on the upper intake EGR issue. The smaller diameter "stove pipe" or "chimney" should help prolong the life of the upper intake plenum, but that's about it. You're still sending superheated gases into a resin intake and after a while, heat will always prevail. Also with the engines is it is said that the DEXCOOL coolant breaks down the OEM lower intake gaskets. And this is a documented issue. You may see coolant pooling in the top of the lower intake manifold. I use the metal Felpro replacements. Also a leak will eventually occur at your plastic coolant elbows. These WILL fail. So use the metal replacements. We have two Buicks and ice done this job of lower intake gaskets, upper intake plenum, and coolant elbow replacements on both of them (2000 Park Avenue Base and 2002 LeSabre Custom) but my LeSabre also needed the front valve cover gasket replaced too, as it was leaking oil onto exhaust manifold, so I replaced both valve cover gaskets on the LeSabre. I have toyed with the idea of modifying the EGR system to prevent those hot gases from going into the motor again. So yeah. My LeSabre is throwing a P0171 code (System too lean bank 1). At times, it's had a loping idle. Very odd. So I'm investigating this at present. Code reader displayed around 4 or 5 possible suspects. This loping idle (that's what I call it) has occured before in my LeSabre, long before I replaced all of the aforementioned items. So if anyone else has thus idle issue, let me know what fixed it. Anyway, good video and explaining the forensics of the intake plenum gasket failure helps people understand. Smart thinking to look in the throttle body and see the coolant where it's not supposed to be. I'm trying Prestone ready to use 50/50 coolant for All Vehicles in my LeSabre now, so only time and mileage will tell. Happy Motoring !

[@bulldogsautomotiveadventur4387]

Test your Prestone antifreeze, I had a viewer get back to me that his was too thin, I did an uncut take where I opened a new gallon and it didn’t test anywhere near -32°. As far as the elbows I’ve been using the metal ones since they came out, and it took them a while to get the metal lower intake gaskets compared to the 3100, 3400, 4.3, 5.0, and 5.7 but we’ve been using them since they became available.

[@bulldogsautomotiveadventur4387]

kzbin.info/www/bejne/nYHLnnaolseef8ksi=2MxTJrF7TYmMnULQ

[@anthonyhfe6450]

2002 LeSabre - related to this video, I figured out the P0171 code on it car - I just replaced the lower intake manifold gaskets, the upper intake plenum and gasket, both valve cover gaskets, coolant elbows, and thermostat. And man this thing idled horribly, like a loping idle like this: womp, womp, womp, womp, womp, womp, so like a rough not smooth idle. Like it felt like it would stall at a light. The Check Engine Light came on So I scanned it and it threw a P0171 code. Well you see that rear vacuum port, that has the big rubber hose (for the booster) going to it and there's another smaller port on top. Well on a LeSabre, that smaller port is not plugged off as shown on the Pontiac in another vid. It has a small line going to it that goes rearward to a component that has an electrical connector going to it and and a second small line too. I'm not sure what this component does. Well I thought I failed to reconnect the small line after doing two days of work, but I did connect it. Guess what I did? Or didn't do? Well, there's a plastic housing that has an O-Ring (there's always a friggin' O-Ring). This has two mounting ears. So you must bend in these two ears/clips of the housing while pushing in the vacuum line housing into the upper intake plenum's rear port. Well I didn't get those two ears pushed in so they locked behind the mating molded in stays, that the ears lock into. Failure to push in this housing and making sure the two ears are locked in will give you a manifold leak and a horrible womp, womp, womp, womp, womp idle. My front vacuum/purge line (the one that's broken in a separate video) seems okay, but it is 22 years old now if it's the original line. I ran out to my car at 1AM and pushed that housing in properly while using a flat head screw driver to bend in the ears while pushing the housing in (against the O-Ring's force too). I had to disconnect both lines and that made it easier for me to push it in squarely. Then I reconnected the two lines. Idle is smooth now. Happy Motoring!

[@bulldogsautomotiveadventur4387]

@@anthonyhfe6450 sometimes that plastic piece isn’t molded correctly and won’t lock into place, I sometimes have to use the old one.

[@hitek9too255]

Good ole GM build quality right there! No wonder why they almost went out of business.

[@chaseww]

I think what it is is these engineers don't know what the hell they're doing. And also it's also saving money. That's all it's about if they could save a dollar on each car million cars, that's $10 million in their pocket. Because guess what, we've been building cars for over 100 years now, there's no excuse anymore to build a car and not to make it right, absolutely no excuse. He's car manufacturers have been doing it again over a hundred years there's no way in hell they're going to convince me of making all these mistakes on these cars and all these recalls and try to convince me that for some other reason, I think what I say to him (the engineer) is bullshit, it's all about money people that's all it's about. My wife's rear seal in her GMC terrain only 39,000 miles just blew, again only 39,000 Miles, yes it was a recall or defect in that rear seal because of the PCV system freezing up or getting clogged with carbon and oil buildup but they usually blow at 80 to 100,000 not 39,000. Again it's all about cheap building crap cheap and saving money no more excuses

[@faronmitchell6702]

Could an intake have a vacuum leak internally? I’m having a P0172 that I can’t find anywhere.

[@bulldogsautomotiveadventur4387]

@@faronmitchell6702 isn’t that a rich code? If it’s on one of these engines check the fuel pressure regulator, might have a split diaphragm and leaking fuel into the vacuum line.

[@Brian-fo8sh]

I am literally doing this job on my 96 LeSabre now. No problems beforehand…just doing this as preventative because it’s just a matter of time. The car has 119k on it. I love this car so much that I have been using it as my daily and leaving my Bronco parked. I have a question for you. I’m using the smaller EGR vent tube but it’s loose in the manifold. How do I hold this in? I can’t have this tube coming loose…that would be catastrophic. Please help. Keep up the great work.

[@bulldogsautomotiveadventur4387]

If it’s a bit loose you set it in the manifold and use a center punch to stake it in, putting a dimple in the base of the tube near the edge will swell it a bit, do this evenly around the edge as needed.

[@Brian-fo8sh]

@@bulldogsautomotiveadventur4387 thanks so much. I was literally lost and ready to just put the original back in and tap it down. Do I use red thread locker as well?

[@bulldogsautomotiveadventur4387]

@@Brian-fo8sh I wouldn’t on that part.

[@Brian-fo8sh]

@@bulldogsautomotiveadventur4387 ok. Thx.

[@Brian-fo8sh]

@@bulldogsautomotiveadventur4387 do you have an email address I could send you some info on max temp and max torque (Permatex) gasket maker in an attempt to hold the vent tube in place, along with staking it. I’m afraid to put this in without doing something to make me feel better. If this smaller vent tube is the fix…I may not ever have to remove it and if I use red thread lock or this gasket maker…could hear from a small butane torch remove it if I ever had to take it out? Thx so much.

[@bosautomotiveservice]

My son was stumped until I found this video. Do you think this would account for getting coolant in the oil, Thanks, Dave !!

[@bulldogsautomotiveadventur4387]

@@bosautomotiveservice the lower intake can let coolant in the oil but it’s rare

[@DetroitMetroRetro]

I had oil mixing into my coolant in obvious levels and when i drained the oil after there was a minimal amount of coolant because i switched to straight water before doing the job trying to flush the oil out of the cooling system Atleast among owners fourms coolant in oil or vice verse in these motors is 9 out of 10 times the LIM I forgot to add we also had zero smoke out of the rear and the car was hot rodded constantly at 110k

[@bulldogsautomotiveadventur4387]

@@DetroitMetroRetro dawn dish soap and water works good to flush the cooling system of oil

[@jeremyking3986]

So could that be causing my anti freeze to turn brown and gunky? 03 lesabre

[@bulldogsautomotiveadventur4387]

No, this won’t allow oil in the coolant, it would allow coolant in the oil. If you have brown or tan gunk on top of your coolant then you have oil intrusion, either engine oil (possible head gasket/ cracked head/ cracked block) or trans fluid (possible trans cooler failure). Check to see if you’re low on one or the other, the most common is a trans cooler failure as it’s inside the radiator.

[@jeremyking3986]

@@bulldogsautomotiveadventur4387 it doesn’t overheat, even on 1 hour drives. Would it make sense to flush it and put new fluid? They guy sold it to me like this, but I’ve been driving it for 3 months. Oil was a quart low when I changed it. Thank you 🙏

[@bulldogsautomotiveadventur4387]

@@jeremyking3986 it depends on if there’s actually a leak, and if it’s actually oil. Since it was like this when you bought it then someone could have poured oil in the wrong hole(seen that a few times), I would flush it real good and drive it for a while.

[@edubb2491]

​@@jeremyking3986mine over heats a bit..temp line to the middle if idling in Warm weather..I also got gunk inside my radiator neck..2000 buick regal with only 79 thousand..I know for sure I have manifold leak ..puddles in valley of engine..I dont think it's Trans cooler line..I think it's what you first said

[@billyshepard5514]

Does anyone make a metal off market one?

[@bulldogsautomotiveadventur4387]

Not a direct replacement, but it can be updated to a series 3 intake I’m told. Personally I’ve never done it.