Intake Manifold Vacuum Leak Questions
05-06-2013, 11:24 PM
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Intake Manifold Vacuum Leak Questions A few days ago I was driving home from work and my SES light came on. I scanned it and came up with P0171. (Lean Bank 1) So I started trying to diagnose the problem. I cleaned my MAF sensor and replaced my fuel filter.
I checked for a vacuum leak using the carb cleaner method. I found a fluctuation in the idle whenever I sprayed the front driver side corner of the manifold with carb cleaner. So I'm assuming that I have a vacuum leak between the manifold and cylinder head causing the SES code.
I've got a 2000 Z28 camaro with a little over 160K miles. It's mostly stock with lid, filter, bellows, P&P TB & GMMG exhaust. It still has the stock ls1 intake manifold and exhaust manifolds along with the emissions equipment. To the best of my knowledge the manifold has never been taken off. (I've owned it for several years now & it was bone stock when I bought it.)
The main questions I have are:
1. I know at the very least I'll have to tear the manifold off and replace the gaskets, but what are the odds the manifold will be cracked or warped and have to be replaced? This is my daily driver and I would like to be as prepared as possible whenever I tear it apart.
2. The leak is minor and doesn't seem to affect the idle. I cleared the code out a couple of days ago and it hasn't flashed back on yet. I know I need to fix this ASAP, but is it safe to drive the car the next few days until I have time to fix it this weekend?
3. All of the part stores around here seem to carry fel-pro gaskets. I tend to try to go with GM parts whenever possible because the quality of part store parts can be hit or miss. Is there any reason I should stay away from fel-pro gaskets and order the GM gaskets?
4. I'm aware this is the perfect time to replace my stock LS1 intake manifold with an LS6 intake manifold. I've always planned to do this, but I don't want to get it tuned until I get headers. If I replace my manifold and pull my EGR & AIR emissions equipment, I know I'll get SES lights. But will this affect my cars computer and make my car run poorly until I get it tuned?
Thanks in advance.
I checked for a vacuum leak using the carb cleaner method. I found a fluctuation in the idle whenever I sprayed the front driver side corner of the manifold with carb cleaner. So I'm assuming that I have a vacuum leak between the manifold and cylinder head causing the SES code.
I've got a 2000 Z28 camaro with a little over 160K miles. It's mostly stock with lid, filter, bellows, P&P TB & GMMG exhaust. It still has the stock ls1 intake manifold and exhaust manifolds along with the emissions equipment. To the best of my knowledge the manifold has never been taken off. (I've owned it for several years now & it was bone stock when I bought it.)
The main questions I have are:
1. I know at the very least I'll have to tear the manifold off and replace the gaskets, but what are the odds the manifold will be cracked or warped and have to be replaced? This is my daily driver and I would like to be as prepared as possible whenever I tear it apart.
2. The leak is minor and doesn't seem to affect the idle. I cleared the code out a couple of days ago and it hasn't flashed back on yet. I know I need to fix this ASAP, but is it safe to drive the car the next few days until I have time to fix it this weekend?
3. All of the part stores around here seem to carry fel-pro gaskets. I tend to try to go with GM parts whenever possible because the quality of part store parts can be hit or miss. Is there any reason I should stay away from fel-pro gaskets and order the GM gaskets?
4. I'm aware this is the perfect time to replace my stock LS1 intake manifold with an LS6 intake manifold. I've always planned to do this, but I don't want to get it tuned until I get headers. If I replace my manifold and pull my EGR & AIR emissions equipment, I know I'll get SES lights. But will this affect my cars computer and make my car run poorly until I get it tuned?
Thanks in advance.
05-08-2013, 03:17 PM
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I have the same mileage on mine, and my intake was NOT warped at all when I replaced my gaskets during an oil pressure sender, knock sensors, & cam position sensor swap.
Just make sure that you follow the torque specs, AND tightening sequence in the Helms factory manual to make sure that YOU do not crack the manifold.
I would also replace the throttle body gasket, AND the EGR pipe into the top of the manifold little round gasket as well.
As far as I know, the car will run fine once you dump the EGR/A.I.R. systems for an LS6 intake swap, BUT, as you've said, your dash will light up like a Christmas tree until you get those codes written out in a tune (IF you have plug-in/visual inspections in your state/area).
Just make sure that you follow the torque specs, AND tightening sequence in the Helms factory manual to make sure that YOU do not crack the manifold.
I would also replace the throttle body gasket, AND the EGR pipe into the top of the manifold little round gasket as well.
As far as I know, the car will run fine once you dump the EGR/A.I.R. systems for an LS6 intake swap, BUT, as you've said, your dash will light up like a Christmas tree until you get those codes written out in a tune (IF you have plug-in/visual inspections in your state/area).
05-08-2013, 09:57 PM
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I have the same mileage on mine, and my intake was NOT warped at all when I replaced my gaskets during an oil pressure sender, knock sensors, & cam position sensor swap.
Just make sure that you follow the torque specs, AND tightening sequence in the Helms factory manual to make sure that YOU do not crack the manifold.
I would also replace the throttle body gasket, AND the EGR pipe into the top of the manifold little round gasket as well.
As far as I know, the car will run fine once you dump the EGR/A.I.R. systems for an LS6 intake swap, BUT, as you've said, your dash will light up like a Christmas tree until you get those codes written out in a tune (IF you have plug-in/visual inspections in your state/area).
Just make sure that you follow the torque specs, AND tightening sequence in the Helms factory manual to make sure that YOU do not crack the manifold.
I would also replace the throttle body gasket, AND the EGR pipe into the top of the manifold little round gasket as well.
As far as I know, the car will run fine once you dump the EGR/A.I.R. systems for an LS6 intake swap, BUT, as you've said, your dash will light up like a Christmas tree until you get those codes written out in a tune (IF you have plug-in/visual inspections in your state/area).
05-09-2013, 12:46 PM
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Actually I haven't tried that. I've owned the car for about five years and a hundred thousand miles and to the best of my knowledge the manifold has never been taken off. So I just assumed the problem was gasket or manifold related.
I'll definitely check it though. Thanks man.
I'll definitely check it though. Thanks man.
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05-09-2013, 06:01 PM
#8
Before you do anything tighten all the bolts to 89 inch lbs of torque, thats about 6 ft lbs. Not very much and if you don't use a torque wrench be very careful you don't over tighten them and strip any. I guaranty the bolts are loose after all those miles.
05-28-2013, 06:50 PM
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Just an update. I went ahead and replaced my LS1 intake manifold with an LS6 intake manifold and my car is running great now. My OEM gaskets were pretty much flat against the contact surface of the original manifold.
I have the SES lights on for EGR & AIR now, but my gas mileage hasn't suffered at all. Last time I checked before I did the install, I got 22 MPG to a tank. In my first tank after the install, I got 23 MPG. I definitely recommend this mod to anyone who finds themselves having to replace their intake manifold gaskets.
I have the SES lights on for EGR & AIR now, but my gas mileage hasn't suffered at all. Last time I checked before I did the install, I got 22 MPG to a tank. In my first tank after the install, I got 23 MPG. I definitely recommend this mod to anyone who finds themselves having to replace their intake manifold gaskets.
