• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

My List of Problems

Tonka98

Full Member
Joined
May 26, 2015
Messages
24
Location
Wilmington De
I bought the truck a month and a half ago. I almost walked off the lot due to some issues I spotted but the dealer (local guy, not a chevy dealer) told me that if I had any reservations he would throw in a year drivetrain warrenty and Id have nothing to worry about..... and so the sucker was born. After taking the truck home and attepting to use the warrenty company, it turns out that they will only cover broken parts. Parts that are worn will not be covered as well as seals and gaskets. So, as it turns out Im now fixing everything myself vs risk an expensive labor bill from the shop in case the warrenty company wont pay up. I love the truck. Its cosmetically in new condition, tows and drives great but I need to get 100k out of it (its got 100k on it now) and would like to fix the following issues to feel better about the motor not crapping out on me.

Issues:
Fuel sending unit went out, the gas gauge reads empty- New pump with sending unit is on the way. Im using the DIC in the meantime. This one should be no big deal. If you have any tips on dropping the tank aside from the ussual let me know.

The oil presure drops to about 5 psi after a good 30 minutes of driving when at idle- If spoken to a chevy Tech and I he said its common for the o-ring going to the oil pump to get worn out and cause a loss of pressure. Ive also heard that the screen commonly gets clogged. Both of those parts are on order as well as the haynes manual so I can figure out how to drop the diff to remove the oil pan.

I get a smoke cloud on cold startup after driving a decent distance. Ive ordered the updated valve cover, the acdelco engine cleaner to clean the pistons of carbon deposits and Ive also turned off the afm with a range module. Im hoping the cover and cleaning will eliminate this cloud of smoke becasue its somewhat embarrassing.

Oil consumption wich Ive read plenty on and Im hoping that the afm off as well as the fixes for the smoke will make this better. Currently Im going through about a qt every 500-750 miles. I understand itll burn some oil but less than a full change between changes would be nice.

My camber angle on the driver side is bad and the guy at the alignment shop told me its because of a 2" lift but ive read on hear that the stock camber adjustments are enough to adjust for a 2" lift? I just put new falken wild country tires on it last night as the previous dune grappler Pos's were balding on the insides of the front set and horrible in my opinion anyway.

Lastly the nav has no idea where it is. Ive given up on this one untill the other issues are fixed but if anyone has some insight aside from its broken please let me know.
 
I dropped my tank by myself in my driveway with nothing more than a couple of Axel stands and a trolley jack. Not particularly enjoyable but doable. The biggest issue i had was disconnecting the fuel lines, especially the one at the front!! On a ramp with a transmission jack i think it would be even easier to drop it, sliding around on the floor makes it a pain. I did think of cutting through the floor to create an access flap, but as my issue was with the pressure sending unit being out of the pump and having a hole into the tank i didnt want to risk a fire.

Oil pressure dropping could actually just be the oil pressure sending unit behind the block. I had a similar issue not too long ago but it was a gauge reading issue and not a mechanical one. Having read through the various DIY's, it looks like a relatively simple swap out with the correct tool without too much breakdown.

The oil / smoke could be the Active Fuel Management system (depending your year) if its the 2007+ which i am presuming, then it could be handy getting a tuning module to deactivate it. Made a big difference with mine without affecting overall Fuel Economy.

No real experience with the others so hopefully others will chime in.

 
Alwaysnosing said:
I dropped my tank by myself in my driveway with nothing more than a couple of Axel stands and a trolley jack. Not particularly enjoyable but doable. The biggest issue i had was disconnecting the fuel lines, especially the one at the front!! On a ramp with a transmission jack i think it would be even easier to drop it, sliding around on the floor makes it a pain. I did think of cutting through the floor to create an access flap, but as my issue was with the pressure sending unit being out of the pump and having a hole into the tank i didnt want to risk a fire.

Oil pressure dropping could actually just be the oil pressure sending unit behind the block. I had a similar issue not too long ago but it was a gauge reading issue and not a mechanical one. Having read through the various DIY's, it looks like a relatively simple swap out with the correct tool without too much breakdown.

The oil / smoke could be the Active Fuel Management system (depending your year) if its the 2007+ which i am presuming, then it could be handy getting a tuning module to deactivate it. Made a big difference with mine without affecting overall Fuel Economy.

No real experience with the others so hopefully others will chime in.

Cool, Ive dropped tanks before just not on an avalanche and they were smaller so Im not too worried about. Ive got a motorcycle jack I plan to use, I figure that will balance the tank nicely on its own.

I forgot to mention that the dealer did change the oil presure sending unit. Of course I cant verify that so maybe he dident.

As for the oil burning, I did put in a range afm disabler over the weekend. Im still getting the smoke, not sure on the consumption yet. Im hoping maybe the smoke is because of the carbon buildup and the cleaning will take care of it. Fingers crossed.
 
What year do you have tonka98
 
I see you have ordered the new valve covers have you installed them yet. Could be a bad PCV valve in the old style covers
 
MS03 2500 said:
I see you have ordered the new valve covers have you installed them yet. Could be a bad PCV valve in the old style covers

I just got it in along with the cleaner. I should have time before the weekend to do both as well as the fuel pump and some airbags I got for the rear. Ill be towing my jeep to Rausch Creek offroad park this weekend so hopefully all that will help.
 
For the oil pressure.
If I'm not mistaken, I think there is a screen or filter in the sending unit hole.
If that screen is clogged, replacing the sending unit won't help.

Wish I could find a bit more for you but, I've got to get back to work.
 
You are right Waz the flex fuel motor have a screen under the oil pressure sensor.
 
Waz said:
For the oil pressure.
If I'm not mistaken, I think there is a screen or filter in the sending unit hole.
If that screen is clogged, replacing the sending unit won't help.

Wish I could find a bit more for you but, I've got to get back to work.

Hmm, so I got the wrong screen then. I got the pickup tube that goes to the pump. Im also guessing that the screen your talking about is alot easier to change than the one attached to the pump. If anyone else has more info on this please post up. Ill do some searching and see what I can find.
 
Alwaysnosing said:
I dropped my tank by myself in my driveway with nothing more than a couple of Axel stands and a trolley jack. Not particularly enjoyable but doable. The biggest issue i had was disconnecting the fuel lines, especially the one at the front!! On a ramp with a transmission jack i think it would be even easier to drop it, sliding around on the floor makes it a pain. I did think of cutting through the floor to create an access flap, but as my issue was with the pressure sending unit being out of the pump and having a hole into the tank i didnt want to risk a fire.

Oil pressure dropping could actually just be the oil pressure sending unit behind the block. I had a similar issue not too long ago but it was a gauge reading issue and not a mechanical one. Having read through the various DIY's, it looks like a relatively simple swap out with the correct tool without too much breakdown.

The oil / smoke could be the Active Fuel Management system (depending your year) if its the 2007+ which i am presuming, then it could be handy getting a tuning module to deactivate it. Made a big difference with mine without affecting overall Fuel Economy.

No real experience with the others so hopefully others will chime in.

Dropping the tank sucked!!!! I had help from a friend and used a motorcycle jack, that part was ok. The part that wasent was the stupid haynes manual that leaves out most of the steps. In the end, after unhooking all of the lines I ended up pulling the driveshaft as well so we could slide the tank out at an angle. Then when reasembling after the last strap wis sinched we heard a pop. Like the dumb optimists that we are, we hoped for the best and got the worst. Im not sure wich line popped or disconnected but when the truck was started it began to dump gas over the top of the tank. Im assuming one of the lines to the pump either cracked or dissconnected slightly? Does the emisions line have enough fuel pumping through to pour out gas? Anyway, we called it quits and ill be dropping the tank again today after work. Also, when reasembling the new pump, do i need the black spacers that came off of the old pump?

O and the kicker! The gas gauge still doesent work  :E:
 
Is it possible the gauge motor for the oil pressure is bad? This was an issue with 2002-2006 trucks where the gauge motors would go bad.. I bought a whole kit of motors to rebuilt my 2003 cluster for less than $50. But I do NOT know if the 2007 has similar motors in the cluster.

Rodney
 
No Rodney 2002 did not have the issue only 03-06 nor did 07 up.
There is a screen under the oil pressure sensor on flex fuel engines, if you change the sensor replace the screen also.
 
Hate to be a buzzkill,  :beating: but, the elephant in the room is, unless you got a killer deal like under $12k, you probably should have gone with your first instinct and walked away. :E: But, now that you are stuck with it diagnosis of the cause of various issues is critical.

I have always believed in start with the simple, least expensive things and try to avoid getting into  the expensive cycle of replacing parts, no solution, replace more parts.

I suspect your fuel level/oil pressure issues are related... more than likely a bad gauge cluster. Cheap to have checked and cheaper and easier to replace than anything you have tried so far.
 
As far as the oil consumption, read this, it may be the rings.
http://chevyavalanchefanclub.com/cafcna/index.php/topic,143434.msg2072202.html#msg2072202

As far as the nav, I had that problem on my '08. It would get lost for awhile and show GPS. The only thing that fixed it was to shut off the truck, restart and let the system find the correct location before driving again. It could take a few minutes or a few tries. Also you can poke around in the diagnostic screen. But I think its just a software glitch that causes it. If it doesn't ever come back then the GPS sensor might be bad or disconnected.

http://chevyavalanchefanclub.com/cafcna/index.php?topic=131781.0
 
Well the gas tank was breeze the second time around now that lines were not stuck and I knew what was needed. The presure line from the pump had a bad o-ring so i swapped that out and had it fixed in a little over an hour. The gauge is still dead but since I was towing this weekend I threw in some rear airbags wich made towing alot nicer. As for the issues. Ive got a crazy week and probably wont get to much but Im hoping these are based off of somthing stupid because the truck does drive great. Even when i get the low presure it doesent sound bad wich leads me to believe its not a case of a worn out engine. As for the smoke, its still there but it has been alot less volume since I turned off the afm. It dident happen imediatly but the last few days it doesent always smoke and when it does its less than before. Im hoping the piston cleaning as well as the updated cover will cure the remaining problem causing that.
 
Tonka98 said:
O and the kicker! The gas gauge still doesent work  :E:
You need to change your cluster, about $300.

Rebuilt will have all new stepper motors for all gauges. Common problems in all GM vehicles.
 
Back
Top