My 07 Denali XL 'build'/Check Engine Lights/Questions

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carrmann

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changed out exhaust manifold gasket, plug wires, valve cover to new style valve cover/gasket.

drove it about an hour today, lowest I saw oil pressure hit was about 13psi in gear/idling at about 550rpm. still see close 35-40 psi at about 1100 rpm cruising

going to do the intake manifold/vlom/valley pan gaskets/orings this weekend hopefully.

update: forgot to mention. zero stalling, stumbling etc that I've seen before with the engine at lower oil pressure.
 
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Geotrash

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anyone have any input on those front shocks, or what goes behind the fuse box in the engine bay? @Geotrash
Sorry I missed this. The service suspension indication is most likely due to the PO putting in passive shocks, and since I don't see any resistors on those connectors, seems reasonable.

And I don't know what that connector is for but it's present on mine and connected. It looks like the wiring for the suspension might go through it but I couldn't trace it out for sure in the dark.

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carrmann

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Sorry I missed this. The service suspension indication is most likely due to the PO putting in passive shocks, and since I don't see any resistors on those connectors, seems reasonable.

And I don't know what that connector is for but it's present on mine and connected. It looks like the wiring for the suspension might go through it but I couldn't trace it out for sure in the dark.
I got Alldata diy and from what I've seen in there that 1 large connector seem to be a suspension relay. the wire next to it is the one in my photos i've posted that looks melted. Thats probably why it doesnt have active air anymore.
Is the rear air/front air tied together? Or do they operate independently? I'd like to use the rear if possible as I plan on towing a small boat/rv, but if I cant use the rear air I'll survive. I'm guessing I'll have to do a post in suspension for help with that stuff.
 

Geotrash

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I got Alldata diy and from what I've seen in there that 1 large connector seem to be a suspension relay. the wire next to it is the one in my photos i've posted that looks melted. Thats probably why it doesnt have active air anymore.
Is the rear air/front air tied together? Or do they operate independently? I'd like to use the rear if possible as I plan on towing a small boat/rv, but if I cant use the rear air I'll survive. I'm guessing I'll have to do a post in suspension for help with that stuff.
There is no air suspension in the front. Only magnetic ride.
 

swathdiver

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Any idea what is supposed to be behind the fuse box in the last picture? Seems something was hooked up there, havent found any good pictures that identify it.
Pretty sure that is for the heated washer fluid that was recalled. Do you have that button between your power outlets under the HVAC controls? You may have 3 to 5 buttons on those early cars.

Use GM OE parts whenever possible. Drill out those busted swaybar bolts and if you get lucky can save the threads, if not, helicoil or put in a bigger thread. There's a nut welded to the top of the bracket. They get really corroded up north and snap off easily since the heads are only 10mm, BTDT!

You're going to want a Tech-2 or similar to get this thing in top form again.
 
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carrmann

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Pretty sure that is for the heated washer fluid that was recalled. Do you have that button between your power outlets under the HVAC controls? You may have 3 to 5 buttons on those early cars.

Use GM OE parts whenever possible. Drill out those busted swaybar bolts and if you get lucky can save the threads, if not, helicoil or put in a bigger thread. There's a nut welded to the top of the bracket. They get really corroded up north and snap off easily since the heads are only 10mm, BTDT!

You're going to want a Tech-2 or similar to get this thing in top form again.
I'm planning on replacing the swaybar/swaybar bolts. Right now theres nothing there at all lol, just the busted bolts. BTDT as well, I'm from up north. Love living down in the south, where my 16 year old vehicle with 170k miles isnt a rust bucket lol. I just took my exh manifold bolts out with a simple ratchet, zero issues.

You convinced me in another thread to get one lol. I dont really know how to use it sadly! Just basic diagnostics so far.
 
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carrmann

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Replaced the valley pan and vlom orings(original ones were quite flat), intake manifold gasket, oil pressure sensor. Zero change with my oil pressure when hot at an idle.

Not sure what else is left other than trying a quart of lucas. Oil pump i guess. Doesn't seem like it would be that to me with 35 to 40 psi at about 1200rpm. Maybe bearing issues? Can't hear any bearing noises though, a tiny bit at first start up(but I've heard other similar engines do the same)
 
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carrmann

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both my 'fresh air' pcv valve hose, and my 'dirty air' pcv valve hoses are cracked etc. The dirty air one i can actually hear sucking/blowing air, if I fiddle with it it stops. I seem to be able to find the 'clean air' pcv one pretty easily online.
The dirty air one I am struggling to get a part # for. IS this the correct part #? 12611592
 

Geotrash

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both my 'fresh air' pcv valve hose, and my 'dirty air' pcv valve hoses are cracked etc. The dirty air one i can actually hear sucking/blowing air, if I fiddle with it it stops. I seem to be able to find the 'clean air' pcv one pretty easily online.
The dirty air one I am struggling to get a part # for. IS this the correct part #? 12611592
Looks right to me. Same as is on my ‘07
 
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