By the way, you don't need to use a torque wrench on the TB nuts. Just a 1/4 drive ratchet wrist tight. Go around in a clockwise pattern and tighten each nut a little bit at a time until you feel an abrupt stop.
Vacuum leak after 3800 intake manifold gasket job
- Thread starter CaliCarLover
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I'm finally going to have time to do this in the next few days.
Does anyone know what the two black o-rings are for? In the top left corner, one bigger than the other: http://ecx.images-amazon.com/images/I/71pGxcxLNyL._SL1500_.jpg
I never used them. They kinda look like the o-rings for the vacuum tree and the PCV valve, which came with the upper intake set.
Also those two orange o-rings are for the coolant elbows right? I bought new coolant elbows that came with o-rings, so I didn't use those either.
Does anyone know what the two black o-rings are for? In the top left corner, one bigger than the other: http://ecx.images-amazon.com/images/I/71pGxcxLNyL._SL1500_.jpg
I never used them. They kinda look like the o-rings for the vacuum tree and the PCV valve, which came with the upper intake set.
Also those two orange o-rings are for the coolant elbows right? I bought new coolant elbows that came with o-rings, so I didn't use those either.
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Don't use PLASTIC coolant elbows. There are aluminum ones available. $10 is cheap insurance. http://zzperformance.com/3800/aluminum-coolant-elbows.html Put silicone grease on them and they slide right in.
I have lots of ZZPerformance parts on my 3800. And there is a tightening sequence for the Upper Intake (plastic) manifold; working from the middle out, similar to head bolt tightening. I can get mine apart in about 20 minutes. Here is a guy on Youtube showing how: https://www.youtube.com/watch?v=YZjEKSqR5Qg
I use a battery hygrometer to suck antifreeze OUT of the radiator and into a clean gallon jug, down to a lower level than the intake manifold. This takes a little time initially, but I end up having no mess on the floor, and I get NO antifreeze into the oil with the manifold off, (have some clean rags handy when you first lift off the manifold), so I don't change the oil. I have done this repeatedly with successful Used Oil Analysis 4K miles later, and I KNOW I got no antifreeze into the oil.
I have lots of ZZPerformance parts on my 3800. And there is a tightening sequence for the Upper Intake (plastic) manifold; working from the middle out, similar to head bolt tightening. I can get mine apart in about 20 minutes. Here is a guy on Youtube showing how: https://www.youtube.com/watch?v=YZjEKSqR5Qg
I use a battery hygrometer to suck antifreeze OUT of the radiator and into a clean gallon jug, down to a lower level than the intake manifold. This takes a little time initially, but I end up having no mess on the floor, and I get NO antifreeze into the oil with the manifold off, (have some clean rags handy when you first lift off the manifold), so I don't change the oil. I have done this repeatedly with successful Used Oil Analysis 4K miles later, and I KNOW I got no antifreeze into the oil.
Did you replace the gasket on the IAC valve, or mess with the screen in the throttle body? The IAC valve will make a loud hiss when it starts up cold.
That engine won't rely on the MAF for about 30 seconds after it starts cold when it switches to closed loop. On a warm start the switch happens almost instantly.
That engine won't rely on the MAF for about 30 seconds after it starts cold when it switches to closed loop. On a warm start the switch happens almost instantly.
Originally Posted By: Ihatetochangeoil
Don't use PLASTIC coolant elbows. There are aluminum ones available. $10 is cheap insurance. http://zzperformance.com/3800/aluminum-coolant-elbows.html Put silicone grease on them and they slide right in.
I even never mentioned plastic elbows at all.. I would never use them. My car already had the aluminum ones (probably was replaced at some time before), but I bought 2 new aluminum ones anyway since they were so cheap. I replaced them already.
So no one knows what those 2 black o-rings are for, that come with the lower intake kit? I called Fel Pro and asked and they didn't know either. But they did confirm that they include extra parts, such as the two sets of side rails (old and new design).
Originally Posted By: sciphi
Did you replace the gasket on the IAC valve, or mess with the screen in the throttle body? The IAC valve will make a loud hiss when it starts up cold.
That engine won't rely on the MAF for about 30 seconds after it starts cold when it switches to closed loop. On a warm start the switch happens almost instantly.
No I didn't even take the IAC valve off while cleaning the throttle body. Could that have messed up the IAC valve?
I am familiar with the loud hiss the IAC makes when cold, but it has a hiss when warm too. Also it has this noise when you rev it, all the time, cold or warm: https://www.youtube.com/watch?v=TZrWDgy40RU (I know it's a Camry in the video, but it's the same air sucking sound)
The MAF screen is damaged. I know it's super fragile, but I'm pretty sure I didn't do it, because it's damaged pretty bad, and I didn't feel any time when I pressed against the screen or felt it give at all. It's ripped in two spots, and the mesh screen is pushed in a little. I was reading that I should probably either replace it or run without it, and not leave it in there damaged, but I need to get a set of snap ring pliers. Plus, would it really cause that noise? I guess it's possible, since all the air goes through there. The noise wasn't there before I replaced the intake, but maybe I did break the screen without noticing, though I highly doubt it.
Don't use PLASTIC coolant elbows. There are aluminum ones available. $10 is cheap insurance. http://zzperformance.com/3800/aluminum-coolant-elbows.html Put silicone grease on them and they slide right in.
I even never mentioned plastic elbows at all.. I would never use them. My car already had the aluminum ones (probably was replaced at some time before), but I bought 2 new aluminum ones anyway since they were so cheap. I replaced them already.
So no one knows what those 2 black o-rings are for, that come with the lower intake kit? I called Fel Pro and asked and they didn't know either. But they did confirm that they include extra parts, such as the two sets of side rails (old and new design).
Originally Posted By: sciphi
Did you replace the gasket on the IAC valve, or mess with the screen in the throttle body? The IAC valve will make a loud hiss when it starts up cold.
That engine won't rely on the MAF for about 30 seconds after it starts cold when it switches to closed loop. On a warm start the switch happens almost instantly.
No I didn't even take the IAC valve off while cleaning the throttle body. Could that have messed up the IAC valve?
I am familiar with the loud hiss the IAC makes when cold, but it has a hiss when warm too. Also it has this noise when you rev it, all the time, cold or warm: https://www.youtube.com/watch?v=TZrWDgy40RU (I know it's a Camry in the video, but it's the same air sucking sound)
The MAF screen is damaged. I know it's super fragile, but I'm pretty sure I didn't do it, because it's damaged pretty bad, and I didn't feel any time when I pressed against the screen or felt it give at all. It's ripped in two spots, and the mesh screen is pushed in a little. I was reading that I should probably either replace it or run without it, and not leave it in there damaged, but I need to get a set of snap ring pliers. Plus, would it really cause that noise? I guess it's possible, since all the air goes through there. The noise wasn't there before I replaced the intake, but maybe I did break the screen without noticing, though I highly doubt it.
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Its been a long time since I did one of these, I can only remember the vacuum port on the rear and possible the PCV using any rings.
One of the rings could be for the MAF and the other I'm not sure. The kit does early to later Gen II engine so there are multiple parts that go unused depending on which one you have.
Does the vacuum fitting have its o ring?
One of the rings could be for the MAF and the other I'm not sure. The kit does early to later Gen II engine so there are multiple parts that go unused depending on which one you have.
Does the vacuum fitting have its o ring?
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Yeah I pulled it out again to double check, the PCV valve fitting and the vacuum port on the rear, all have all the required o-rings.
Yeah I think they are just extra for other variations of the engine.
Things keep coming up, but when I have time, I'll just redo the intake manifold job and report back.
Yeah I think they are just extra for other variations of the engine.
Things keep coming up, but when I have time, I'll just redo the intake manifold job and report back.
With a fully warmed engine. What's the ltrim abd strim values? What's the IAC value?
Not sure if your engine uses the same version of the EGR stove pipe as other, but it's a common failure. I had a leak that I couldn't find that turned out to be the stove pipe.
Not sure if your engine uses the same version of the EGR stove pipe as other, but it's a common failure. I had a leak that I couldn't find that turned out to be the stove pipe.
Originally Posted By: 97 GTP
With a fully warmed engine. What's the ltrim abd strim values? What's the IAC value?
Not sure if your engine uses the same version of the EGR stove pipe as other, but it's a common failure. I had a leak that I couldn't find that turned out to be the stove pipe.
+1 on the EGR pipe. It can be very easy to break when removing or installing the intake manifold.
With a fully warmed engine. What's the ltrim abd strim values? What's the IAC value?
Not sure if your engine uses the same version of the EGR stove pipe as other, but it's a common failure. I had a leak that I couldn't find that turned out to be the stove pipe.
+1 on the EGR pipe. It can be very easy to break when removing or installing the intake manifold.
Will try to get those values for you. Don't have an OBDII scanner that reads sensors yet, but I'll probably get one of those Bluetooth ones I can use with Torq.
Isn't the EGR stove pipe the silver thing that's included with the new upper intake kit? Or are you talking about the corrogated EGR tube under it?
http://s883.photobucket.com/user/michiganmusclecar/media/GM V6/3800/DSCF5942.jpg.html
They're both in this picture, which one are you guys talking about?
Isn't the EGR stove pipe the silver thing that's included with the new upper intake kit? Or are you talking about the corrogated EGR tube under it?
http://s883.photobucket.com/user/michiganmusclecar/media/GM V6/3800/DSCF5942.jpg.html
They're both in this picture, which one are you guys talking about?
I don't come on here too much, but I was referring to the corrugated tube.
Originally Posted By: CaliCarLover
Will try to get those values for you. Don't have an OBDII scanner that reads sensors yet, but I'll probably get one of those Bluetooth ones I can use with Torq.
Isn't the EGR stove pipe the silver thing that's included with the new upper intake kit? Or are you talking about the corrogated EGR tube under it?
http://s883.photobucket.com/user/michiganmusclecar/media/GM V6/3800/DSCF5942.jpg.html
They're both in this picture, which one are you guys talking about?
Originally Posted By: CaliCarLover
Will try to get those values for you. Don't have an OBDII scanner that reads sensors yet, but I'll probably get one of those Bluetooth ones I can use with Torq.
Isn't the EGR stove pipe the silver thing that's included with the new upper intake kit? Or are you talking about the corrogated EGR tube under it?
http://s883.photobucket.com/user/michiganmusclecar/media/GM V6/3800/DSCF5942.jpg.html
They're both in this picture, which one are you guys talking about?
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