2005 Escalade ESV Gas Filling Issue

[bajajoaquin]

I've got a 2005 Escalade ESV with 147k on it. It's fairly new to me. One issue I'm having is that either my gas gauge is miscalibrated and it reads that my tank is about half full when it's really full, or there's an issue with the filler neck/vent system preventing me from filling it. Given some of the issues and recent changes, I now suspect the filler neck/vent. Symptoms:

I've never been able to fill it. Even when driving for a bit with the low fuel light on, I have never been able to put more than 25 gallons in it. With a 31 gallon tank, I'd expect to get more in. The gauge has read a max of 3/4 full.

I had the in-tank fuel pump replaced recently, a job that required dropping the tank. Since then, I can't get it past half tank indicated easily. This could be a further miscalibration of the float, or the filler neck could have been misadjusted.

However, on a long road trip recently, I tried trickling gas in on low flow to see if the vent was just plugged. I got it to take another couple of gallons before it overflowed and spilled a pint out on to the ground. The gauge read about 5/8 or 3/4 full.

When I stopped for gas again, I only put in 10 gallons before the nozzle stopped. I did the math on miles traveled, and I would have needed to get 25 mpg to use 10 miles in that time. So it's super unlikely. I just went ahead and avoided spilled gas and just refilled every 150-180 miles for the rest of the trip.

So questions: Filler/vent or gauge? Is this a DIY resolution? I'm reasonably handy, but I don't have a good place to do the work if it is going to take more than an afternoon.

Also, according to Tahoe Forum Thread, sounds like the cannister pellets may have clogged the vent. That thread also recommends seeing if a scan gauge agrees with the gas gauge. Any recommendations on a scan gauge?

 

[OR VietVet]

Very common problem that starts with over filling the fuel tank. When the nozzle clicks off, that is it. That is when the system is working properly on your rig. If the rig has problems filling, like yours does then I see why you attempt to fill more and more. On a recent trip I had problems at a Chevron with the filler clicking off but I know my evap system is all completely new. As I expected, it was the station pump itself because I have not had any problems since. Anyway, I see members here replacing this one piece and that one piece and continue to have problems. I say, bite the bullet and replace the entire system, like I did. But, I am a "thousandaire" so I do things like that.

 

[bajajoaquin]

Until Sunday, I was not an over-filler. I agree. When it clicks off, I stop. So whatever issue is there originated either with the previous owner or since the gas tank was dropped and reinstalled a week or two ago. But I'm still not sure if it's "just" the filler or if there's also an issue with the gauge, since I had an issue previously which seems to have gotten worse.

When you say replace the entire system, what system and parts are you referring to, exactly?

 

[nonickatall]

There is an evap system which has a vent valve and an charcoal canister which is designed to prevent toxic fumes from being released into the environment.

The vent valve is automatically open, when the vehicle is switched off, so that the air can escape when refueling. This then escapes via the activated carbon filter and the valve.

When the vehicle is started, the valve is closed so that the gases produced in the tank are drawn off via the engine and burned there.

If this ventilation no longer opens or the activated carbon canister is sealed, the air cannot escape when refueling and then what you have as a problem happens.

Here is a good explanation of the system.

 

[OR VietVet]

Until Sunday, I was not an over-filler. I agree. When it clicks off, I stop. So whatever issue is there originated either with the previous owner or since the gas tank was dropped and reinstalled a week or two ago. But I'm still not sure if it's "just" the filler or if there's also an issue with the gauge, since I had an issue previously which seems to have gotten worse.

When you say replace the entire system, what system and parts are you referring to, exactly?

I see that @nonickatall supplied a video about the evap system. I was not insinuating or meant to say that you caused the problem. Likely all started with the previous owner. The fuel gauge not reading correctly would be a separate issue but maybe, just maybe, that are related.

 

[bajajoaquin]

Thanks. Sorry if I sounded defensive.

I don't have a check engine light, but you're suggesting I replace both valves and the charcoal cannister?

 

[nonickatall]

The video was not because of the engine light but because the principle of the evap system is explained well here.

The evap system mainly checks if it is tight. If your vent valve hang closed, that might not result in an error code, but you can't refuel.

I wouldn't just replace things now. First analyze, then repair.

The vent valve is attached to the tank in front of the rear axle and can be relatively easily be removed. You can then check whether it is free and open, maybe add 12 volts to check if it switch.

Otherwise I would take a look at the canister, but it hangs a bit stupidly on the tank at the front a little above the tank and is not easy to remove without a lift.

But I would look for those places first...

 

[OR VietVet]

IMO, replace all, valves, sensors, solenoids, cannister and lines. Perfect time to drop tank and see what is going on with sender. Please tell me it is a GM pump and not aftermarket.

 

[bajajoaquin]

Thanks to you both.

It's probably aftermarket. I didn't replace it myself. I had a check engine light on for lean condition both banks (read that on my scangauge II). No vacuum leaks, but mechanic was saying that it ran lean under load, so was likely the fuel pump/filter assembly needing replacement. While I have had the filling issues, the fuel pump seems to have resolved my lean condition. Anyway he's usually pretty good about not buying the cheapest stuff available, so it's probably not the bargain, but also probably not a GM replacement part.

 

[nonickatall]

Did your problems with the fueling start after the replacement of the fuel pump?

 

[bajajoaquin]

They changed. I could never get more than 25 gallons in the tank before. In reading up on this platform, I saw that gas gauges frequently go out of calibration. I guessed that was the issue. Now, I can't get more than 10 or 12 gallons into it after the gas tank removal/reinstallation. That's leading me to evaporative emissions issues.

 

[nonickatall]

Then it is very likely that the mechanic did a mistake, because the evap system is mostly connected to the gastank and the evap lines are on top of the gas tank. So maybe he squeezed or kinked one of the plastic lines while reassembly.

If it wasn't too long ago, I would go to the workshop and complain about the work.

 

[bajajoaquin]

Both. When I bought the truck in November, I couldn't get more than 25 gallons into it. I suspected the gauge because I found that listed as a common issue with this platform when I was looking up stuff prior to purchase.

After the fuel pump replacement, the issue became more severe, and I could only get it to half way on the gauge. I didn't test it thoroughly because I was on the road and didn't want to run the tank down into reserve while I was in the Arizona desert. But I believe it's the difference between an indicated 3/4 tank previously and an indicated 1/2 tank now. From my original post:

"However, on a long road trip recently, I tried trickling gas in on low flow to see if the vent was just plugged. I got it to take another couple of gallons before it overflowed and spilled a pint out on to the ground. The gauge read about 5/8 or 3/4 full.

When I stopped for gas again, I only put in 10 gallons before the nozzle stopped. I did the math on miles traveled, and I would have needed to get 25 mpg to use 10 miles in that time. So it's super unlikely. I just went ahead and avoided spilled gas and just refilled every 150-180 miles for the rest of the trip."

So I have reason to believe it's the evaporative system.

 

[nonickatall]

On the right side in the pic you will see a metal sheet. Between this and the tank is the evap system's plastic tubing from the vent valve (right bottom) to the charcoal canister (top right side).

If the mechanic did not insert these lines correctly and then pushed the tank up with hydraulik jack and screwed it tight, he may have squeezed this line.

I would say that this is the most likely reason, because if he would for example forgotten the vent valve connector, the vent valve would stay open and you would receive an engine lamp and message "check gas cap"...

 

[bajajoaquin]

got it. The double reply was because I didn't see my first response on a second page, so I took the time to type up a longer response.

I called the mechanic and he's going to take a look at it and basically said the same thing you did. Hopefully it will get sorted quickly and without additional cost.

 

[Fless]

On the right side in the pic you will see a metal sheet. Between this and the tank is the evap system's plastic tubing from the vent valve (right bottom) to the charcoal canister (top right side).

If the mechanic did not insert these lines correctly and then pushed the tank up with hydraulik jack and screwed it tight, he may have squeezed this line.

I would say that this is the most likely reason, because if he would for example forgotten the vent valve connector, the vent valve would stay open and you would receive an engine lamp and message "check gas cap"...

@bajajoaquin That pic is of my flex fuel tank when it was on the ground; if yours is not FF then some of the routing may be different.

While the tank is down you might see if the mechanic would gently blow some compressed air through the lines to make sure they're clear. Not a lot of pressure, since that can bunch up any charcoal pellets if there are any in the lines. He should be able to easily blow (lung) air through the canister.

Also might be a good time to pull the fuel pump back out and verify the level function with the cluster gauge.

 

[willinnashville]

I fought this a few years ago on my 05 Denali. I replaced the evap stuff, but the fix ended up being charcoal pellets in the vent lines. Once those were blown out by my mechanic (worth it for me since I don't have a lift) it's been fine ever since

 

[Blk00ss]

Before you start replacing everything under the sun, I'd try something.

We had the fill issue with my son's '05 starting around 140K. . You couldn't fill fast at the pump, it had to be slow. If you tried to lock the pump handle it would overflow. So, like others have suggested I started replacing things. Evap solenoid etc. Nothing worked. It still wouldn't take fuel quickly and would overflow if tyring to squeeze handle all the way. I quickly found a lot of people talking about charcoal pellets in their fuel lines which basically keeps the tank from being able to breath more or less. So one day I decided to crawl under and disocnnect the two main lines coming from tank to charcial canister box. As soon as the lines released, charcoal came spilling out. So I knew right away my charcaol canister, like many many others had broken down. Drove around with lines disconnected for a bit (it doesn't hurt anyhting) and even tried to get fuel. Still no fill. I had seen many others (there are even YT videos) drop the tank and blow the lines out via air compressor. I didn't wanna drop the tank. So I took a small funnel, shoved it into the fill neck where you would put the gas pump when fueling, put shop vac on blow side and stuck it in the funnel blowing air into the tank. I would hold it there for a 5 or 10 seconds then release and then back on. I kept doing this for a while. As you're doing this, you can actually see the tank swell, then relax, swell then relax. As I was doing this, charcoal pellets were spilling out like crazy from the evap lines going from tank to canister. I did this a few different times over the next week and eventually, no more pellets would come out. And...she started taking fuel faster than she ever had and we've owned it since 35k.

Many people will say replace things, but if you dig into this issue, you'll find (like me) that replacing parts wasn't typically the answer. The evap lines filling with charcoal pellets is INCREDIBLY common. It may be your issue, or maybe not. But thought I would give my .2 cents. And you don't need a mechanic for this. I knew if what I tried didn't work, I would drop the tank, but I knew if I could get the tank to pressurize, it may work. I had seen others who did the same. It worked perfect for me. and, my fix was done over a year ago.

 

[willinnashville]

I wish I'd thought of that - that's a great idea

 

[Blk00ss]

I actually got the idea from watching a youtbube video of a guy who had dropped the tank, and blew the lines free. Someone in the comments of that video said screw all that, he disconnected the evap lines and stuck a leaf blower in the filler neck and turned it on. Same as me, when he did this, pellets come out of the lines at an alarming rate. His issue was fixed. So I tried the same... voila. Also, I wouldn't worry about being gentle with the air. I don't know what the blow side of my shop vac is, but it blows hard. And honestly, after having done this and being so neck deep into the issue prior to fixing, I don't think gentle pressure would have resolved my issues at all.