Ideas? Help with a DOD/ AFM Deleted 2011 Escalade 6.2

[Jeffdylanproctor]

I'm sure there are knowledgeable people out there regarding the GMT900 platform and I would appreciate some advice.

To start, I have a 2004 Escalade 6.0 and much experience with the GMT800 platform, and thus have hitherto avoided the GMT900 trucks because I didn't want to deal with the AFM/DOD system. I got married and wanting to continue being debt free, my wife let me pay cash for her to have a truck of her own, and she found this 2011 Escalade 6.2 she really wanted. The seller told me it had been recently AFM/ DOD deleted so I bought it. It has the smooth valley cover along with other indications of the work being done so I trusted the people that it was so.

The 2011 Escalade 6.2 runs decent most of the time, but has problems losing power when at a light cruise, feeling like it is choked and "surging," being much weaker than my 2004 with the 6.0. The issue doesn't always appear, and it is much more common under my wife's driving habits than mine.

It has an enjoyable exhaust on it, and it never sounds like a truck in the AFM/ DOD mode, it just feels a little starved for fuel.

The truck has a lot of power when it has it, it idles just fine and if you drive aggressively it will never have a hiccup; but if you ever let it slip into a moment of weakness, it gets really weak.

If you pull out from a "rolling stop" or are in town in traffic, it feels like it is in overdrive but wont come out, with something of a "surging" feel. Using the manual shift mode helps, but not a lot. The problem is very obvious if you're trying to pull up a hill while it is behaving choked like this. It will be like this for several seconds until you force it to wake itself up. Again, it's more like it "surges" back to life than kicking itself awake.

It shows a P0011 Code most of the time, but not always.

I wonder if they did not properly finish the AFM/ DOD delete with a tune? Does anyone know where to start looking for what is causing the problem of power loss?

 

[rdezs]

Your camshaft is probably off by a tooth, or you have a defective VVT actuator. The person who did the delete may have reused it, but they're not reusable. It's possible that's the problem. If you have no clue who did the AFM delete and what components were used, I'd be inclined to remove the front cover.... See if the oil pump is new. Replace the timing chain and tensioner with a good quality one, along with a new genuine GM actuator. It's also possible that actuator was not torqued down properly.

Nothing wrong with purchasing a vehicle with the AFM deleted.... But I would want to see the receipts for what was installed in the engine.

I would be hesitant to continue driving the vehicle until you verify visually the camshaft timing and the associated components. That code means your valve timing is too far advanced. Bad things will happen if a valve contacts a piston.

 

[Jeffdylanproctor]

Thanks for the reply, I have been wondering about the VVT system.

I just went and looked at the engine, and it has a very new Dorman Front Cover on it, but peering behind the water pump I can tell the Cam Phaser Magnet is not new, it is aged in a way that looks like it is the original with the truck. I should have mentioned in my original post that when I first noticed the problem I was glancing around the engine bay and discovered a box with a used Cam Position Sensor tucked by the batter, and the one sticking out of the Front Cover was clearly new. I think whoever was working on this was barking up the VVT tree, but didn't bother pulling the water pump to actually see what was going on.

I think the first thing I should do is order a new Camshaft Phaser Magnet (Part 12653140) and Seal (Part 32279) along with a VVT Camshaft Position Solenoid (Part12682000)

I can't imagine if they didn't replace the Camshaft Phaser Magnet that they would have replaced the VVT Camshaft Position Solenoid behind it...

But then comes the issue of the timing and all that. If everything is correcting as far as having the cam and crank in agreement, isn't there a learning sequence or something the computer has to go through? Forgive me for being new to this platform.

Is there anything wierd or strange about installing the VVT Camshaft Position Solenoid? Some precise ritual that has to be done so the electronics know how to interact with it all?

 

[rdezs]

There is a relearn procedure to be done after replacing either the camshaft position sensor or the crankshaft position sensor, or any of the timing components. But it will always start up and run fine..... In fact you have to warm the engine up to operating temperature to perform the procedure, set the parking brake.... And you're bidirectional scanner or Tech 2 device will walk you through the procedure. When you have met the parameters, gas pedal to the floor to 4,000 RPM and let off and your scanner will tell you if it completed. Look online for a bi-directional scanner, make sure it has the crank relearn function. A pretty basic one that includes that and about 30 other items is quite affordable these days.

It sounds like somebody changed the camshaft position sensor prior to your purchase..... Trying to figure out what's wrong. With that trouble code indicating your valve timing is too far advanced, I would wait to do a relearn until you visually check the timing gears are in alignment.

You will need to disconnect the battery and remove your starter. Look on Amazon for a crankshaft holding tool for an LS engine. Simply bolts in place of the starter and holds the flex plate to keep the crankshaft from rotating. It's okay to use an impact to remove the crankshaft bolt. Also pick up a new crankshaft bolt, they are torque to yield and not supposed to be reused. Remove water pump. Then the timing cover. No need to remove power steering, alternator or AC compressor.

Remove oil pump. The oil pick up tube can be removed without dropping the oil pan, it has the one bolt. Takes a little bit of finesse. I would recommend a Melling 10296 oil pump. It comes with a +10 PSI red spring already installed. (Along with an oem pressure spring, and then another spring for even more pressure that you won't need) This is a higher pressure and higher volume pump that works excellent on AFM deletes where you keep VVT.

Rotate engine till the dot on the crankshaft gear is pointed straight up, and there's an arrow of sorts on the cam gear that should be pointed straight down at it. If the arrow is pointed up, rotate the crankshaft one more turn. If they do not come in alignment and are off by one tooth or more, there is the problem.

With the crankshaft timing mark straight up, install the crankshaft locking tool in place of the starter.

You will see the camshaft actuator is threaded through the camshaft VVT pulley and retains it to the camshaft. Break that loose, remove it and discard.

Pull the VVT pulley off the end of the camshaft, with the chain on it. As it comes off you can take the chain off and remove it from the crankshaft gear.

Remove the timing chain tensioner. Discard.

Remove the three torx bolts and remove the camshaft retaining plate and discard.

Install your new camshaft retainer plate, torque to specifications.

Install your new timing chain tensioner, leave the metal clip in it for now which keeps it compressed to the left.

Here's where it gets interesting. With the new timing chain around the crankshaft sprocket, and around the VVT camshaft sprocket, you're going to slide the camshaft sprocket over the end of the camshaft so that the pin in the camshaft engages the camshaft pulley. You need to be able to pull the camshaft toward you and ensure that that pin is fully engaged while you thread the new actuator in. Couple options on this.

1. With the intake off, and the valley plate removed, you can keep the camshaft pushed forward with a small pry bar pushing against the side of a cam lobe. Be extremely careful not to scratch the surface of the lobe.

2. Or use a long bolt threaded the same as the VVT actuator, just screw in a couple threads into the camshaft so you can lightly pull on it while you get the pulley in place with the pin all the way in.

The trick here is doing that while keeping the timing marks in line. You may have to do it two or three times.

When you were sure you have it, carefully remove the bolt if that's what you used and gently start threading in the actuator. Go ahead and tighten it up snugly. 30 ft lb of torque or so. If the VVT gear looks like it's sitting straight, go up to about 60 foot pounds of torque. At this point push and pull on the VVT gear. If the cam slides in and out a perceptible amount, the pin did not get engaged in the hole and start over. If it is engaged and the cam does not feel like it's moving at all, this is where you should put a dial indicator gauge on it to check the end play. .001" to.003" is what you're looking for. Barely perceptible. If the timing marks are still in alignment, pull the pin to the tensioner and rotate the engine over three or four times completely and check the timing marks again.

Then reassemble the oil pump, timing cover, the electrical solenoid on the front, camshaft position sensor, harmonic balancer and water pump.

Start it up, get it warmed up, plug in the bidirectional scanner and complete the relearn.

 

[rdezs]

You will need a harmonic balancer puller and installation tool. A gear puller if you're going to replace the crankshaft gear. And of course a torque wrench.

When installing the oil pump, Melling recommends putting in two opposing bolts barely finger tight, rotate the crankshaft several revolutions, then torque to specifications.

Personally, I tend to be a perfectionist and go overboard. I would have too many questions regarding the prior AFM delete job. I would probably pull the cylinder heads and the lifters and check them out as well as the camshaft that was used. (Did the guy even replace the camshaft? Did he only replace the AFM lifters and leave the other ones?) Did he plug the oil towers under the valley cover with the steel plugs? (Inexpensive, available on Amazon, just tap them in. Additional insurance in case the o-rings under the new valley cover ever fail)

Food for thought.....

 

[rdezs]

As for requiring a tune, not necessary if he used an oem non AFM camshaft. But we have no idea what he used, right?

 

[donjetman]

I had my timing cover off last summer and changed the cam position sensor, seal, and phaser magnet, etc.
https://www.tahoeyukonforum.com/threads/valley-cover-crank-pulley-etc.149036/
There was no need to do a re-learn.

 

[Jeffdylanproctor]

Thanks so much, I'm going to save (maybe even print) your writeup, Rdesz, as it's is the sort of precise advice I was looking for, especially the recommendation for the Melling 10296 Oil Pump, as I've been trying to decide which is the best one to go with. The truck has oil pressure, but its lower than I'd like it to be.

Is there an affordable Bidirectional Scanner that's you would reccomend?

Other details on the truck are that it appears to have gotten new Head Gaskets recently, and the heads are clean like they had gone to a shop or something. Someone has been in the engine, but I can also tell they weren't the most thorough with it. I wish I knew what parts were in there, particularly the Camshaft, but I guess I will try to figure it out as I go.

Still, I've got this Escalade and here I am, I must enjoy the Tahoes which are, and not the long for ones that could have been.

 

[rdezs]

Before I purchased my Tech 2, I used the following bidirectional scanner. For the price, was quite useful. Still have it in the toolbox.....

OBD2 Scanner Code Reader for Chevy/GMC Full System Diagnostic Scan Tool, Transfer Case ABS SRS EPB CKP Oil Reset 30+ Special Function Check Engine Code Reader with Battery Registration Bi-Directional https://a.co/d/eqBwRjf

 

[rdezs]

Strange, I tested the link and it opens up on Amazon in Spanish? Might be a browser setting at my end

 

[solli5pack]

+1 for a Tech 2 clone. I paid about $350 I believe about 2 years ago. Paid for itself multiple times already.

 

[rdezs]

Hopefully you get the timing cover off and the timing is off one tooth. At least then you have it definitive answer. I would almost bet money that it's one tooth advanced. Your ECM is telling you the valve timing is over advanced.... I doubt that the ECM is wrong.

As posted above, you can replace these components and if the timing is correct it will run just fine without the relearn. The relearn just lets the ECM be more precise, which usually results in slightly better fuel mileage and power after it's completed.

 

[rdezs]

Note.... The camshaft actuator that screws into the camshaft, and the magnetic solenoid that goes in the timing cover should both be genuine GM/ AC Delco. You don't want to mix and match different brands. Same for the camshaft position sensor. Keep it to a genuine GM or AC Delco. Unless you want to go back in there

 

[rdezs]

I personally use the Cloyes timing set with the tensioner. Replacing the crankshaft gear and camshaft gear is your option. Over 120,000 miles I always replace both. Which many would say is overkill.

One last thing.... Do not forget to pull the pin out of the tensioner before putting the cover on. And put that pin somewhere so you can find it later on, like in the cup holder in the car. Go wake up in the middle of the night not remembering if you pulled it out or not, and you'll get dressed real quick and run out to the shop see if it's really in the cup holder before you'll be able to go back to sleep. Don't ask me how I know that, LOL

 

[rdezs]

.... take pictures as you go. During disassembly and after assembly. Your camera phone comes in handy when trying to get a straight-on view of the timing marks. But when you remove that cover, if the oil pump and the camshaft gear are colored gold.... Somebody did not replace them. Here is a photo of an L94 engine right after the timing cover and oil pump was removed. Note the timing marks

 

[rdezs]

The gold is normal residue.... You can use it as an indicator though to identify if the pump or timing gear was replaced. Also note the two bolts for the tensioner are also gold stained.

 

[Charlie207]

Strange, I tested the link and it opens up on Amazon in Spanish? Might be a browser setting at my end

The link opens to an english-language version for me. Probably VPN or browser settings.

 

[rdezs]

I was just contemplating that trouble code from the ECm regarding valve timing to far advanced. I just realized that it's possible it was trying to retard the timing like it should at low RPMs and the actuator was not working properly. That would trigger the same code I think. That could be due to an aftermarket unit, ie a cheap Chinese one. Or reusing the old one. Or not being torqued down properly.

The camshaft retainer plate that's held on by the three torx bolts should look brand new and clean. If it looks gold, that raises some serious questions on the competency of whoever did the AFM delete and how many corners were cut to do it cheaply

 

[rdezs]

If it looks like a new oil pump, check the number on it to identify the pump. It's possible the guy went with an inexpensive pump that doesn't have the pressure or volume for the vvT system... That actuator that screws into your camshaft uses oil pressure to retard the timing at lower RPM..... If it can't do that it will report valve timing is too far advanced

 

[rdezs]

Depending on what you find.... You'll get a clear picture what you're dealing with. I'm afraid if it was me, I'd take it all apart, pull the heads, check the lifters, remove the cam and get the part number so I know what I'm dealing with. That sounds like a lot of work, but not as much if you have to go back in a second time. Plus that way you know everything is done right with good quality parts.