View Full Version : 07 Avalanche problems

07-30-2013, 10:02 PM
Well what does this all mean!?!?!? These are out of my 07 Avy with the 5.3L, about 90k miles, and most likely the oil related problems I described in my other thread.








Super Scout
07-31-2013, 07:18 AM
It means you need new spark plugs.
Humor me, and get the weasel piss you call oil out of the crank case and see what happens lol. I have changed spark plugs on these engines at 120,000 miles and they don't look like that. Hopefully your computer reprogram used.
Just on a side note, do you think there is any chance the dealer pulled the orginal plugs out and threw those in ? Those look like hell for only 90,000 miles. I know they are the OEM plugs, but damn.

07-31-2013, 10:39 AM
I believe there is a TSB for this that involves changing the valve covers and lifters.

Btw, some of that crud is a build up of fuel additives.

07-31-2013, 09:02 PM
Those look like hell wow... So Consensus seems to be new plugs, real engine oil and run the balls off it...hahaha wouldn't expect anything less. Loan it to me i'll clean her clock out Josh.

08-05-2013, 02:20 PM
Well, I think I fixed it, knock on wood.

New valve cover with PCV valve.
New AC Delco plugs.
New MSD wires.
AFM disabled, V8 mode all the time.

She runs like a bat out of hell and gets the same mileage, maybe better.

I let CRC Upper Cylinder Cleaner soak in the cylinders with the plugs out for a few hours. I hit the starter and blew it out, then started it up and man did she smoke for about 10 minutes, but I have no more smoke on start up and the truck runs great.

Oh, and I did put Mobile 1 synthetic oil back in it. So there.

10-07-2013, 01:04 PM
2500 miles and no issues! No smoke! Most amazingly, no more oil consumption!

2" leveling kit installed in the front.

Plasti-dip sprayed the emblems and wheels. I think I'm going to do the rest of the chrome around the grill and definitely the faded black plastic triangles behind the back doors. Also going to order a Go Rhino push bar, finish off the "police" look. I need to roll up to shooting competitions looking like a tier 9 deep space operator.

Tonight I'm changing the transmission filter and fluid (just what's in the pan, no flush), transfer case fluid, and differential fluids so it will be ready for the road trip to the Knob Creek machine gun shoot this weekend in Kentucky. It's close enough to the 100k mile mark so might as well change everything. Probably switch the coolant from orange to green when I get back.


01-28-2014, 01:54 PM
99k miles, no more signs of oil consumption or smoke, thankfully, but I'm having another unrelated issue.

So I had the common problem with surging, engine power reduced, and numerous throttle related CEL codes. I seem to have fixed that by taking apart the connector on the throttle body and putting it back together, no issues with those things any more. This is a common Avalanche problem because the connector at the throttle body is lame and it looks like the plastic cover on top of the motor pushes on the harness and applies sight tension to the connector, pulling it apart slowly. Just my luck it would finally have an issue during the coldest winter EVER.

While I was in there, I cleaned all the gunk from the throttle body seat, and I quickly learned that creates a high idle with the fly by wire system.

Yesterday I did the idle relearn instructions I found online, idle for 3 minutes, off 1 minute, idle for 3 minutes, and drive.

This did nothing to change the current problem I'm experiencing. It's like the engine rpms aren't reducing to idle when I let off while the throttle while the truck is moving.

When the truck is just sitting in park, idling, the rpms are around 600. If I'm drving fast and coming to a stop, I can feel the truck wants to keep going, but I can control it with the brakes, nothing dangerous, and if I bump it into neutral, the rpms go to about 2300 or so, just high revving like the throttle is stuck, and as the truck slows down (while still in neutral) the rmps decrease, until I come to a complete stop and the engine is back at that 600 rpm idle. If I'm driving slow or crusing around a parking lot I can feel the truck wanting to speed up as well.

I currently have no CEL and this issue has been consistent since before I did the idle relearn procedure.

So my question is, do I need to cave and pay the dealer to hook up a "Tech 2" gizmo and perform a real idle relearn or is this a throttle body issue? Is the throttle body now bad because I got some carb cleaner in it or something and it needs replaced?

Also I put a GoRhino push bar on the front, and the plasti dip is holding up nice.


01-28-2014, 03:07 PM
You need a good code reader to better understand whats going on. There are a bunch of codes that won't set of the CEL, but are there. Some readers are better than others and can dig deeper. You might not need the Tech II but you need someting that will get the deeper codes.

Other than that I'm pretty much useless on the new gas engines.

Super Scout
01-28-2014, 08:15 PM
Sell, buy mids 90s GM truck. No more issues, ever :)

01-28-2014, 09:06 PM
Put a carb on it

01-29-2014, 10:32 AM
Clean the grounds and check the tps... oh, sorry. Not an XJ.

My satrun had that issue, it was a combo of a cracked vaccuum hose and a dirty EGR valve. I was also told that changing all the temp senders could help... but thats a saturn. might be just shitty gm parts.

02-03-2014, 02:59 PM
The dealer did an idle re-learn with the Tech II for $30 and it seems the truck is back to normal. I can't complain about that price.

I put new pads and rotors on the front Saturday and I'm back to loving my Avalanche. The extra breaking I had to do with the truck's throttle acting up finished off the pads I had. I went with Advance's Wearever rotors and the "premium" Wagner Thermoquiet ceramic pads, mainly because the Wagners are the only pads Advance sells that they will exchange one time under warranty for wear. Hopefully the rotors last. I was debating springing for the Wagner rotors as well for an additional $20 each until I saw no store stocked them.