99 Lumina 3.1 Intake gasket replacement procedures

Document ID# 339144

1999 Chevrolet/Geo Lumina

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Intake Manifold Replacement Upper

Removal Procedure

Important This engine uses a sequential multiport fuel injection system. Connect the injector wiring harness connectors to their appropriate fuel injector or exhaust emissions and engine performance may be seriously affected. For the correct injector wiring harness connector-to-fuel injector connection procedure, refer to Engine Electrical.

Disconnect the battery ground (negative) cable. Refer to Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical. Disconnect the vacuum hose connection from the throttle body air inlet duct. Disconnect the wiring harness connection from the intake air temperature (IAT) sensor in the throttle body air inlet duct. Refer to Intake Air Temperature (IAT) Sensor Replacement in Engine Controls - 3.1L. Remove the throttle body air inlet duct. Drain the engine coolant from the cooling system. Refer to Draining and Filling Cooling System in Engine Cooling. Remove the accelerator control and cruise control cables with bracket from the throttle body. Remove the wiring harness from the retainer. Refer to Accelerator Controls Cable Bracket Replacement in Engine Controls - 3.1L. Disconnect the following wiring harness connectors from the throttle body: Throttle position (TP) sensor Idle air control (IAC) valve Disconnect the (left) front spark plug wires. Refer to Spark Plug Wire Harness Replacement in Engine Electrical. Disconnect the wiring harness attachment clips. Camshaft position (CMP) sensor wiring harness Left hand spark plug wire harness Engine wiring harness Remove the nut from the coolant pipe to the throttle body. Disconnect the thermostat bypass pipe coolant hoses from the throttle body. Refer to HVAC. Remove the engine mount struts. Refer to Engine Mount Strut Replacement . Rotate the engine forward for access. Disconnect the right spark plug wire retaining clips. Remove the spark plug wires at the coil pack. Remove the ignition coil bracket with the coils, the purge solenoid, the vacuum canister solenoid, the vacuum lines, and the electrical connections. Refer to Ignition Control Module Replacement and Evaporative Emission (EVAP) Canister Purge Valve Replacement in Engine Controls - 3.1L.

Disconnect the vacuum hose at the manifold air pressure (MAP) sensor and upper intake manifold. Remove the manifold air pressure (MAP) sensor and the bracket. Refer to Manifold Absolute Pressure (MAP) Sensor Replacement in Engine Controls -

3.1L.

Disconnect the emission control vacuum harness. Disconnect the vacuum hose connections from the upper intake manifold. Vacuum booster hose Automatic transaxle vacuum modulator hose Heater and air conditioning vacuum source hose Fuel pressure regulator Remove the drive belt. Refer to Drive Belt Replacement . Remove the front generator brace. Refer to Generator Brace Replacement in Engine Electrical. Remove the rear generator brace. Refer to Generator Brace Replacement in Engine Electrical.

Remove the exhaust gas recirculation (EGR) valve. Refer to Exhaust Gas Recirculation (EGR) Valve Replacement in Engine Controls - 3.1L.

Remove the right hand upper intake manifold bolts and studs.

Remove the left hand upper intake manifold bolts. Remove the upper intake manifold.

Remove the upper intake manifold gasket.

If replacing the upper intake manifold, remove the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 3.1L.

Clean the seal surfaces on the manifold with degreaser.

Installation Procedure

If removed, install the throttle body. Refer to Throttle Body Assembly Replacement in Engine Controls - 3.1L.

Install the upper intake manifold gasket.

Install the upper intake manifold. Loosely install the left hand upper intake manifold bolts.

Loosely install the right hand upper intake manifold bolts and studs.

Notice Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Install the upper intake manifold bolts and studs. Tighten Tighten the upper intake manifold bolts and studs to 25 N·m (18 lb ft).

Install the exhaust gas recirculation (EGR) valve. Refer to Exhaust Gas Recirculation (EGR) Valve Replacement in Engine Controls - 3.1L. Install the rear generator brace. Refer to Generator Brace Replacement in Engine Electrical. Install the front generator brace. Refer to Generator Brace Replacement in Engine Electrical. Connect the vacuum hose connections to the upper intake manifold. Vacuum booster hose Automatic transaxle vacuum modulator hose Heater and air conditioning vacuum source hose Fuel pressure regulator

Connect the emission control vacuum harness. Install the manifold air pressure (MAP) sensor and bracket. Refer to Manifold Absolute Pressure (MAP) Sensor Replacement in Engine Controls -

3.1L.

Connect the vacuum hose at the manifold air pressure (MAP) sensor and the upper intake manifold. Install the ignition coil bracket with the coils, the purge solenoid, the vacuum canister solenoid, the spark plug wire retainers, the plug wires at the ignition module, the vacuum lines, and the electrical connections. Refer to Ignition Control Module Replacement and Evaporative Emission (EVAP) Canister Purge Valve Replacement in Engine Controls - 3.1L. Return the engine to the proper position. Install the engine mount struts. Refer to Engine Mount Strut Replacement and Engine Mount Strut Replacement . Connect the thermostat bypass pipe coolant hoses to the throttle body. Install coolant pipe nut to throttle body. Connect the wiring harness attachment clips. Camshaft position (CMP) sensor wiring harness Left hand spark plug wire harness Engine wiring harness Connect the left hand spark plug wires. Refer to Spark Plug Wire Harness Replacement in Engine Electrical. Connect the wiring harness connectors to the throttle body. Throttle position (TP) sensor Idle air control (IAC) valve Install the accelerator control and cruise control cables with bracket to the throttle body. Install the wiring harness to the retainer. Refer to Throttle Body Assembly Replacement in Engine Controls - 3.1L. Fill the cooling system with engine coolant. Refer to Draining and Filling Cooling System in Engine Cooling. Install the throttle body air inlet duct. Connect the wiring harness connection to the intake air temperature (IAT) sensor in the throttle body air inlet duct. Refer to Intake Air Temperature (IAT) Sensor Replacement in Engine Controls - 3.1L. Connect the vacuum hose connection to the throttle body air inlet duct. Connect the battery ground (negative) cable. Refer to Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical.

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Intake Manifold Replacement Lower Removal Procedure

Important This engine uses a sequential multiport fuel injection system. Injector wiring harness connectors must be connected to their appropriate fuel injector or exhaust emissions and engine performance may be seriously affected.

Disconnect the battery ground (negative) cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical. Remove the upper intake manifold. Refer to Intake Manifold Replacement . Disconnect the radiator inlet hose from the engine. Refer to Radiator Hose Replacement - Inlet in Engine Cooling.

Disconnect the thermostat bypass hose from the thermostat bypass pipe and lower intake manifold pipe. Remove the thermostat bypass pipe. Remove the left (front) valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement . Remove the generator. Refer to Generator Replacement in Engine Electrical. Remove the right (rear) valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement .

Disconnect the engine coolant temperature (ECT) wiring harness.

Disconnect and remove the fuel injector and manifold air pressure (MAP) wiring harness.

Remove the fuel pipe clip bolt.

Remove the fuel pipe clip.

Disconnect the fuel feed pipe from the fuel injector rail. Refer to Fuel Hose/Pipes Replacement - Filter to Engine in Engine Controls - 3.1L.

Disconnect the fuel return pipe from the fuel injector rail. Refer to Fuel Hose/Pipes Replacement - Filter to Engine in Engine Controls - 3.1L.

Remove the fuel injector rail. Refer to Fuel Rail Assembly Replacement in Engine Controls - 3.1L. Remove the power steering pump from the front engine cover and reposition. Refer to Power Steering Pump Replacement in Power Steering System.

Disconnect the heater inlet pipe with heater hose from the lower intake manifold and reposition. Refer to Heater Pipe Replacement - Inlet in HVAC.

Remove the lower intake manifold bolts. Remove the lower intake manifold. Remove the valve rocker arms and the push rods. Refer to Valve Rocker Arm and Push Rod Replacement .

Remove the lower intake manifold gaskets and seals. Clean the lower intake manifold gasket and seal surfaces on the cylinder heads and the engine block. Clean the gasket and seal surfaces on the lower intake manifold with degreaser. Remove all the loose RTV sealer.

If replacing the lower intake manifold remove the engine coolant temperature (ECT) sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement in Engine Controls - 3.1L.

If replacing the lower intake manifold remove the water outlet bolts. Remove the water outlet.

If replacing the lower intake manifold remove the thermostat. Installation Procedure

If removed, install the thermostat.

If removed, install the water outlet. Notice Refer to Fastener Notice in Cautions and Notices.

Install the water outlet bolts. Tighten Tighten the water outlet bolts to 25 N·m (18 lb ft).

If removed, install the engine coolant temperature (ECT) sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement in Engine Controls -

3.1L.

Important All gasket-mating surfaces need to be free of oil, and foreign material. Use GM P/N 12346139 (Canadian P/N 10953463) or equivalent to clean surfaces.

Install the lower intake manifold gaskets. With gaskets in place supply a small drop 8-10 mm (0.31 -0.39 in) of RTV Sealer GM P/N 12346141 (Canadian P/N 10953433) or equivalent to the 4 corners of the intake manifold to block joint (1). Connect the 2 small drops with a bead of RTV Sealer that is between 8-10 mm (0.30-0.39 in) wide and 3.0-5.0 mm (0.12-0.20 in) thick (2). Install the valve rocker arms and pushrods. Refer to Valve Rocker Arm and Push Rod Replacement . Notice Refer to Fastener Notice in Cautions and Notices.

Important All lower intake manifold bolts need to be cleaned, free of any foreign material, and reused only if new bolts are unavailable. Use GM P/N 12345382 (Canadian P/N 10953489) or equivalent and apply to the old intake manifold bolt threads.

Important Manufacturer recommends the center bolts be fully torqued before the diagonal bolts to assure proper seal ability.

Important Lower intake manifold bolts in location 6 and 7 should be torqued to specification using a crows foot type tool.

Install the lower intake manifold. Install the lower intake manifold bolts. Tighten Tighten the lower intake manifold bolts in sequence to 7 N·m (62 lb in) on the first pass. Tighten the lower intake manifold bolts (1,2,3,4) in sequence to 13 N·m (115 lb in) on the final pass. Tighten the lower intake manifold bolts (5,6,7,8) in sequence to 25 N·m (18 lb ft) on the final pass.

Install the heater inlet pipe. Install the heater inlet pipe nut. Tighten Tighten the heater inlet pipe nut to 25 N·m (18 lb ft).

Install the power steering pump to the front engine cover. Refer to Power Steering Pump Replacement in Power Steering System.

Important Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.

Install the fuel injector rail assembly. Install the fuel injector O-rings using GM P/N 12345616 (Canadian P/N

993182). Install the injector nozzles into the lower intake manifold injector bores. Press on the injector rail using the palms of both hands until the injectors are fully seated. Install the fuel injector rail bolts. Tighten Tighten the fuel injector rail bolts to 10 N·m (89 lb in).

Connect the fuel return pipe to the fuel injector rail. Refer to Fuel Hose/Pipes Replacement - Filter to Engine in Engine Controls - 3.1L.

Connect the fuel feed pipe to the fuel injector rail. Refer to Fuel Hose/Pipes Replacement - Filter to Engine in Engine Controls - 3.1L.

Install the fuel feed and return pipe retaining clip. Install the fuel feed and return pipe retaining clip bolt. Tighten Tighten the fuel feed and return pipe retaining clip bolt to 8 N·m (71 lb in).

Connect the thermostat bypass hose to the thermostat bypass pipe and lower intake manifold pipe. Connect the radiator inlet hose to the engine. Refer to Radiator Hose Replacement - Inlet in Engine Cooling.

Install and connect the fuel injector and manifold air pressure (MAP) wiring harness.

Connect the engine coolant temperature (ECT) wiring harness. Install the right (rear) valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement . Install the generator. Refer to Generator Replacement in Engine Electrical. Install the left (front) valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement . Install the upper intake manifold. Refer to Intake Manifold Replacement . Connect the battery ground (negative) cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical.

-------------------------------------------------------------------------------- Document ID# 339149

1999 Chevrolet/Geo Lumina

wrote in message news: snipped-for-privacy@4ax.com...

Wow! Thanks a million Silver!!!...

Here is the replacement procedure I used on a 2000 Century courtesy of Ian aka 'Shiden Kai' If you do a search for 'Shiden Kai" you'll come up with a a revised procedure where he uses a box wrench to pry on the rockers to remove the pushrods without loosening the nuts. I loosened the nuts and used a Fel Pro Problem solver gasket and new manifold bolts with pre-applied sealer. That was 18 months and 20,000kms ago and all is well.

Thanks aga> I have not removed an intake manifold in close to 30 years.

By the time we are done doing the job (we charge 98 dollars an hour), it's usually a 750-800 dollar job. The labour charge is about 6.0 hrs, but a good tech can easily do it in 2.0 hrs. I wrote up a detailed explanation of how to do this job a while back. I'll paste it below and you can do with it what you want. It should be pretty close to what you will encounter with your vehicle. It was written for a van, but the procedure is very similiar for your car. There will be some difference at the throttle body area and the fuel lines for the injector rail go way down under the exhaust. Don't bother trying to disconnect any fuel lines, simply remove the nut that holds the fuel lines against the rear head and then position the injector rain and lines up out of the way and bunjee cord it up to the hood. It's too much work to try and disconnect the fuel lines and then snake them out under the exhaust crossover pipe. You will see what I mean when you get there.

Ian

Ok, I'll go over the basic procedure for the van.

First step would be to drain the coolant. This year, you need a 1/4 inch square drive ratchet and preferably a short extension. Use the 1/4" ratchet to turn the drain c*ck counter clockwise about an 1/8 of turn, then you have to pull the drain c*ck out while turning it further.

Next...pull the rubber hood seal off at the front of the cowl area...then you can pull off that plastic piece that covers the wiper motor area (passenger side of the engine compartment.

Pull the air filter housing and snorkel..usually, I find it easier to remove the rubber section first, and then you have more room to remove the air filter cover and air filter. There are a couple of electrical connections on the snorkel and the MAF sensor, unplug them...and then follow that wire harness back and unplug everything else on it, except where it plugs into the coil pack ( oh yeah, I'm going to give you the "faster" version). So you should have a couple more sensors at the throttle body, a red connector at the evap solenoid and then a harness clip at the coil pack. You can position this harness back over the coil pack. Remove the front three spark plug wires at the coil pack. Unhook all the clips that hold those wires to the engine, but don't bother to take the wires off the front plugs, just lay the wires over the front of the rad support. Remove the vacuum booster hose at the upper plenum.

Remove the two bolts that secure the coil pack bracket to the upper intake plenum (10 mm head). Now you want to remove the MAP sensor which sits bolted to a small bracket on the upper plenum right in front of the coil pack. You will need a 7 mm socket or wrench to undo the two long screws that hold it in place. Then unhook the vacuum lines and the electrical connector and lay the sensor and vacuum lines somewhere. Now you can remove the upper plenum bolts. At the passenger rear side of the upper plenum, there is a small brace that goes from the alternator to one of the bolts in the upper plenum. Get that brace off and then you can take that one plenum bolt out.

Now go to the back of the engine, you need to find the EGR pipe that comes up to the upper plenum and EGR valve. The temptation is to remove the valve, but don't bother. Just remove the bolt that holds the flexible pipe to the upper plenum. There is also a small nut that holds the Transmission filler tube to a stud on the upper plenum. You need to remove that and push the filler tube off that stud. There is also one nut at the throttle body that holds a coolant pipe in place, remove that and disconnect the two small throttle body coolant hoses at the back of the engine there. At this point you should be able to remove the upper plenum. Do "not" bend the coil pack bracket up to give yourself clearance. This makes it very difficult to start those bolts properly later on. Just slide the upper plenum out from underneath it. You may notice that I said nothing about the cables to the throttle body. I do not disconnect them, just leave them on the plenum and flip the plenum upside down and off to the side. It will just sit there.

Next, you need to remove the fuel rail and injectors. There are two 10mm head bolts that hold the rail to the lower intake, and one that holds the fuel lines to a bracket at the rear of the rear head. Remove all three, carefully pry/pull the fuel injectors and rail out of the holes. Take a close look at the injectors once you have them out, any o-rings that have come off need to be retrieved from the intake manifold area. Sometimes they will just be loose, other times, they are stuck in the injector holes. Again, I don't disconnect the fuel lines, just position the rail and lines off to the side somewhere.

There is a heater pipe that goes into the lower intake at the rear of the engine. You need to simply loosen the nut that holds it to a stud at the rear of the rear head, and then you can pull the pipe out of the intake. Note: replace that o-ring seal.

There is also a heater pipe and bypass pipe assembly that runs along the front of the front valve cover. That is the same pipe that had the two small throttle body hoses connected to it. Remove it, and either move it off to the side, or disconnect the "quick connect" fitting (sometimes they aren't all the "quick" and so I just leave them).

Now you can remove the front valve cover, if you need room to get at the one bolt, remove the left engine strut and you can get a run at the bolt. Then loosen the two rear valve cover bolts that you can see. One will be under the alternator, the other is under the coil pack. In both cases, there is just enough room to completely loosen the two bolts.

Now you have to deal with the power steering pump. Remove the small plastic shield that sits right above the water pump pulley (this just give you a little more clearance for the ps pump pulley). Now, remove the serpentine belt. Then remove the three bolts that hold the pump to the engine, you can access them thru the bolts in the pulley. They are 13 mm bolts. Now, you must loosen the ps pressure hose fitting at the pump. Use a 5/8 wrench and just loosen it until the hose will be able to move. In other words, don't completely remove the hose. Now, reach your hand down the two ps hoses and you will find some plastic clips that the hoses are in. Pop the Pressure hose (left one as you look down at the two hoses) out of the plastic clip. Now, you should be able to pull the pump up and lay it down between the front of the engine and windshield washer bottle. You may need to fiddle with the rubber return hose, as there is a bracket in it's way, you can move the hose around the bracket.

At this point, remove the lower intake bolts (8 of them) and the upper rad hose from the lower intake. The intake should now slide out from under the rear valve cover. Trust me, it comes out. Now you have to loosen the rockers arms enough so that you can get the push rods out. The rear rocker arm bolts can be reached, even though the rear valve cover is in place. Just loosen each rocker arm just enough to be able to remove the push rods. Keep them in order, as it's important that you don't mix them up.

Clean up your gasket surfaces..etc. Then install your intake gaskets to the head first, then the push rods. Short pushrods to the intake valves, long to the exhaust valves. Be meticulous about cleaning the front and rear surfaces of the block and the intake manifold, as this is where the RTV sealer goes. Also clean the joint between the rear valve cover and the cylinder head and where the intake manifold will meet the two of them. Do not mess with the rear valve cover gasket, just make sure it stays up in it's groove. Before you install the intake, make sure you have a nice bead of RTV on the front and rear mating surfaces, and put a dab of RTV in that corner where the rear v/c and head and intake will meet. From there, it's pretty well just the reverse of the removal procedure. Don't bother trying to tighten those two rear valve cover bolts until you have torqued down the intake manifold. Then they will just slide right in. Also, when you install the upper plenum, you are going to slide it back under the coil pack, and then engage the EGR pipe and the throttle body coolant hoses. Take your time here, and make sure everything is where it should be before tightening down the intake bolts.

Hope this helps, and all goes well. The procedure for the Century will be almost identical, other then the Trans dipstick tube.

Ian

GM

Coolant and/or oil leaks. GM reports that many of its 1999-2003 mid- size cars and minivans with the 3.1 or 3.4L V6 (VINs J, E) are susceptible to springing oil and/or coolant leaks at the lower intake manifold gasket. The complaints you're likely to get irom customers can vary from oily spots on the driveway to continually having to top up the coolant reservoir with antifreeze. The Low Coolant light on the dash could also illuminate. A new-design intake gasket with superior sealing qualities (Part No. 89017279) is now available to eliminate both leakage issues.

GM says you must install upgraded manifold bolts with preapplied threadlocker (Part No. 11588915, short bolts; Part No. 11588914, long bolts) to get the benefits of the new gaskets sealing qualities. New torque specs and a new tightening sequence for the bolts are also on the menu (see illustration).

Here's the info you'll need to do the job: Begin by tightening the four vertical (inner) bolts to 62 in.-lbs. Follow that up by tightening the four diagonal (outer) bolts to the same 62 in.-lbs. Now go back to the vertical bolts and torque them to 115 in.-lbs. Complete the tightening sequence by torquing the diagonal bolts to 18 ft.-lbs. GM cautions that if you don't use the new torque specs in the exact sequence indicated, you could be opening yourself up to a comeback.

Thanks also, anon...

Hello, please i also need information of the procedure of how to replace intake gaskets for chevy lumina 3.1 1999, please send me information if you have it. Thanks.