Lean Bank 1 Code - surging Idle

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bkboatnsleds

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I get a Chk Engine light, and a lean bank 1 code...

I also get a surging idle.

I'm thinking intake manifold gaskets... Thoughts?
 

NC_John

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Get a can of ether/starting fluid and spray it around the intake manifold while the engine is idling if you think there might be a leak. If the idle changes you've found the leak.

Exhaust leaks typically don't have any symptoms other than noise and maybe some exhaust smoke.

I wonder if an o2 sensor going bad would cause that? If its reading too rich could it cause that bank to be fed leaner and cause your problem? Will/can an o2 sensor foul and cause problems before it outright fails??
 
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bkboatnsleds

bkboatnsleds

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Well i hooked up my scan tool... and watch the o2 sensor reading while I put some carb cleaner by the intake gaskets...

YOu could watch the readings spike!! So tonight I put a new METAL updated set of FelPro gaskets on the motor. Runs smooth as silk now.. 100%
 

Rwayne

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You made it sound so easy. Did you do it yourself? I need to do the same because it only gets worse with colder weather..silk smooth sounds nice. If you did DIY, what kind of money and time am I looking at? Thanks for any help

Sent from my HTC Sensation 4G using Tapatalk
 
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bkboatnsleds

bkboatnsleds

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Yep did it myself - I should have done a DIY Video - It was easy really. Honestly Its way more intimidating than it actually is.. Just take your time and its not bad. I got the updated gaskets were like $60.00 (I have a napa account) These gaskets have a metal support area rather the plastic ones..

I can walk you through it best I can w/o photos or looking at it so bear with me...

Remove the airduct and hoses all attached to airbox and Throttle Body (T.B.)

Remove the top plastic cover on top of the motor.
Remove the plate under it with 3 bolts holding on wire harness cover.

Unplug all the fuel injectors. These have a little gray locking clip on them that must be removed before the injectors will come off. Pull off the clips, then just squeeze on the little plugs and pull them out - unplug all 8 of them.

unplug the 2 wire harness (each side of motor) that are in the center by the ignition coils (Have to remove blue lock tab first)

Remove the coolant hose that runs through the T.B. (Bottom side of it) there is one on each side of it. It MAY be easier to remove these once the intake is loose and you can lift it higher to make it easier to get in..

Remove fuel lines going to fuel rail (You can leave fuel rail on the intake) You will need the special tool to remove the fuel lines (This is the ONLY 'special' tool you will need. (Something like these colored things... http://www.sellitnowstores.com/ebay\carolyn/3July20MatcoMasterDisconnectSetMDS399/DSCN0183.JPG...

Make sure all the sensors are unpluged - one on the way back against fire wall, TB has a plug, etc... anything attached to the black intake with a plug.. Unplug it. Emissions sensor up front can be unbolted if you cant get the vac line off of it.

Make sure all the vacuum lines are disconnected - large one goes to break booster - pop it out..

Basically just unplug everything from the intake or anything mounted to it.

At this point you can loosen the intake if you have not done so already 8 mm bolts around the left and right side of the intake. The bolts will STAY IN the intake.. just spin them until they are all the way free, but they will not come out.

You should be able to free the intake.. It may help to have a buddy there to hold some of the wire harness out of the way so you can sneak it out..

Once its out, and on the workbench...

I took a shop vac and sucked any crap out of the valley before it had a chance to fall into the open ports on the motor. ALSO if you need to do knock sensors.. NOW is your time.. (its the 2 black hockey pucks on the motor your looking at)

Once motor is clean - make sure you use come carb cleaner to clean the carbon areas where the new gaskets will mate.. I used a carb cleaner soaked rag to clean it down to the shiny aluminum

On the intake take your old gaskets off the bottom - they should un snap.. Then also clean that surface on the plastic intake too. Its now also a good time to replace the TB Gasket as the TB comes off with 3 bolts and there's a gasket back there too.. may as well.. Also a good time to CLEAN the intake of the T.B.

So now its all clean - both surfaces (Motor and intake) are ready to go!! Grab your new gaskets which now will not clip on like the old style Assuming you got the right ones.. They sit on the motor side, and there is a 'hoop' on each one that sits ON TOP of the head bolt - do NOT remove any head bolts to put the gasket on (It will make sense when your looking at it)

SO the gaskets are set on the motor - now just do everything in reverse - set the intake on (again having someone to hold the wires out of the way helps..

Once the intake is on - try to hand thread a bolt on each side to make sure its ligned up right. I also tightened them slowly - dont crank one tight until they are all started... Tighten them like a tire where you criss cross the pattern. There probably is a specific pattern to follow - i don't know it. I do know there are 2 specific torque specs to follow - a low one.. then you come back and tighten more.. I just tightened them all fairly snug - then went back and tightened them up. They will bottom out when tight, so you'll know.

Just plug all the wires, Vac Lines, tubes injectors .. DOn't forget the lines under the T.B.

Remember most of the plugs you CAN"T screw up.. for a few reasons.. either 1 it will not reach to anywhere its not supposed to be plugged into.. or otherwise it simply will not plug into somewhere its not supposed to be..

Just look over everything - make sure no vac lines or connections are left behind.. 1 on back of intake by firewall.. Hose on back driver side of intake..

Its that easy!! If I can help.. ASK! :) I paid someone the first time to do the job (Almost $400) and I'll say this was my first time doing it and it took me well under 2 hours.. Not a bad job at all - basic tools needed.. 8 / 10 mm sockets and just that fuel tool (Auto zone may even loan them!)

Hope this helps someone.
 

Rwayne

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I did mine a while back. Don't regret it a bit. Thanks. Easy do it yourself, fuel line clips were kinda tricky for me. Everything else was a breeze. Took a trip to autozone for a fuel line dis-connector tool and about 4hrs. Could've taken a lot less time too.
 
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