Chevrolet Cruze Forums banner

1 - 20 of 132 Posts

·
Premium Member
Joined
·
435 Posts
Discussion Starter #1 (Edited by Moderator)
Go back to COMG- The Cruze Owner's Maintenance Guide


Here's the definitive way to properly increase your tank capacity from 12.x gallons to 15.x gallons.

First, get the fuel pump module from any 1.4L Cruze as long as it's NOT the ECO M6.

Next step is to release pressure in your fuel lines. I just pushed in the schrader valve that's on the fuel rail and had a rag handy to catch the fuel. After that remove the fuel tank. To do this you have to remove all the ECO specific underbody cladding. There's 3 pieces. 2 that run the length of the car and 1 smaller one that runs side to side by the fuel tank. They're easy to remove, just a bunch of 10mm plastic nuts and 2 10mm bolts.

After those are out of the way I lowered the rear section of exhaust by unbolting it right behind the catalytic converter. Just 2 13mm nuts and it'll lower enough for the tank to clear.

Disconnect the fuel filler hose at the tank, vent tube that's right next to it, main fuel line and vent line next to that.

There are 4 electrical connectors to unplug. 1 is on the vapor canister and this one is the hardest one due to lack of space. 1 is on the fuel line, 2 are on top of the fuel pump module. The only way to get to them is to lower the tank. To lower the tank you just unbolt the 2 straps that hold the tank in. 13mm bolts. I bent them down and out of the way. They're easy to bend and bend back without any damage. The only other way to do this without bending them is to remove the rear axle beam.....you decide. :eek:)

After you're sure all wires and tubes are unplugged lower the tank and slide it out the passenger side. Mine only had a few gallons in it so it was pretty light. DO not do this unless your tank is almost empty.

Once the tanks out and on the ground on top of the fuel pump module there are 2 tubes to unplug.

After that the locking ring is un-done with a punch and hammer. Just tap the tabs counter clockwise and it'll come right off. Once that's off the module just lifts right out.

Put the new one in and everything is reverse order to put it back together.

Enjoy your higher capacity!

Here's some pictures.

Fuel tank out of the car:



ECO M6 12.x gal on left, ECO A6 15.x gal on right:



Here's what it looks like with the tank removed. You can see the straps I'm talking about here:



Exhaust unbolted here to allow it to drop down enough for the tank to clear:



My tank had about 3 gallons in it when I swapped out the modules, here's filling the tank with the nozzle on full throttle after it shut off by itself:



Here's my gauge showing full WITHOUT trickle filling:
 

·
Premium Member
Joined
·
6,918 Posts
My tank had about 3 gallons in it when I swapped out the modules, here's filling the tank with the nozzle on full throttle after it shut off by itself:
Your very accurate with your 3 gallon guess.

On my 1LT I had the low fuel warning come on as I was pulling up to the pump. It took 13.1gallons to fill, that leaves a 2.5gallon reserve when the low fuel warning comes on(assuming 15.6gallon tank size).
 

·
Administrator
Joined
·
15,685 Posts
Would you happen to know what the part number for this is so we can look it up on gmpartsdirect.com?

A 600+ mile range would be all too easy with the Cruze Eco now.
 

·
Banned
Joined
·
168 Posts
To do this with "just a few gallons" in the tank is inviting disaster. Gasoline is extremely volatile. When you first lift the fuel pump module out of the tank, the vapor space in the tank above the remaining gasoline will be "rich" - meaning above the upper explosive limit. But as soon as you expose that vapor space to air (by way of the big hole in the tank where you took out the module) the vapor space may very well drop into the explosive range. A gasoline-air mixture in the explosive range is extremely easy to ignite from any tiny spark, including static electricity. If this happens when you are kneeling over the tank, you could be severely burned and injured. And since it is a plastic tank, the tank will be on fire suddenly and depending on where the car is, the flames could spread to the car - and it's mostly plastic nowadays. So, please, please, please - if you are going to attempt this modification, figure out some way to drain the tank completely and then let it "air out" for a couple of hours - go get a Starbucks giant coffee and relax while you relish the idea of going 600 miles between fill ups. Can't drain the tank completely and in too much of a hurry to let it air out? It would actually be safer to do this modification with the tank completely full. This eliminates any vapor space, so there cannot be a vapor-air explosion in the tank. 15 gallons of gas weighs about 90 pounds, so get to the gym and do some bench presses for a few weeks before doing the job with a full tank. Sorry to rain in this parade, but as a Fellow of the Society of Fire Protection Engineers and a Senior Member of the American Institute of Chemical Engineers, I am bound by a code of ethics where I must point out unsafe ideas and practices. The safest way to go 600 miles between fill ups is to get on the wait list for the new Cruze Diesel!! Because I spent my whole career preventing fires and explosions in chemical plants, paint plants, pharmaceutical plants, etc., I don't know how many lives I saved with my recommendations and designs for safe operaations/maintenance procedures, but I may have just saved yours if you were thinking of doing this mod "with a few gallons in the thank." Happy Motoring!!
 

·
Administrator
Joined
·
25,375 Posts
While I agree with Erastumus that the risk of fire is definitely there and that an empty tank of gas is definitely more flammible than a full tank, I also don't think it's a bad as he states. You always have to be careful when working around gasoline - anyone who has tuned a gas lawnmower is aware of this risk. The risk mitigation is to release the pressure from the tank in a controlled and "safe" method. To do this simply open the gas cap before starting. I don't think this modification can be done with a full tank as the tank will tend to rock on whatever surface you place it on thus spilling gasoline out of the tank, raising the risk of fire. I would definitely do this with as few gallons as possible in the tank and only after I had released the tank pressure by bleeding the fuel line to the engine and the fill pipe of extra fuel and vapor pressure.

The part path at GMPartsDirect.com is "All Vehicles - 2012 Chevrolet - Cruze - ECO - Fuel System - Fuel System - Fuel System Components - Fuel pump assy". It's item 9 on the diagram and there are two options - one without 13 gallon fuel tank and one with 13 gallon fuel tank. The fuel pump price is $335.37 MSRP / $174.39 GMPartsDirect.

One question - does the new fuel pump come with a new seal and retainer, and if not, should these be replaced as well?
 

·
Premium Member
Joined
·
435 Posts
Discussion Starter #10
Take caution as you may but i'd love to know how you empty the tank completely then vent it for hours before removing the fuel pump module? I don't know of a single shop nor mechanic who'd attempt that.

Getting it as light as possible "only a few gallons in tank" and common sense should keep things safe. If a person wanted to go all safety overboard you could get some bonding straps, put one on your wrist, the other on the tank and bond both to ground. That would eliminate any chance of static discharge.

Anyways all safety disclaimers aside, I wanted to do this the RIGHT way and I have and wanted to make sure others knew what was needed to do this.

As far as the part number goes I'm sure someone will find it and post it. There's only 2 fuel pump modules for the 1.4L cars. ECO M6 or not. That's it.
 

·
Premium Member
Joined
·
1,943 Posts
Very nice write-up however I think I'll just stick to my cheap and simple way of just adding an extra 2 gals (instead of 3) by pouring in the extra 2 gallons from my gas can after my fillup. It goes in as fast as you can pour and cost about $5 (for the gas can).
 

·
Registered
Joined
·
1,334 Posts
I know GM "W" Bodies such as the Oldsmobile Intrigue had a ball valve check valve assembly as part of the filler tube connection at the tank. On this car you couldn't pass a siphon hose down the fuel filler tube, as you couldn't get by this ball check valve.

In the Olds Intrigue there was an access panel to the fuel tank from behind the rear seats, inside the car, and you could drain the tank from there.


firehawk- Did you notice a check valve on the filler assembly near the tank? If I recall Alldata says drain the tank, but doesn't say how.. Therefore I'd assume it would be out the filler tube, but be carefull. If your siphon hose hits resistance, your up against that check valve assembly.. Don't break it.
 

·
Registered
Joined
·
64 Posts
Thanks for pioneering this! Looking at the photos of the fuel pump assemblies, it looks as though you may be able to remove the black clip from the Eco pump assembly to raise the float or valve. If you get a chance, could you take a look at your original pump and verify if this is true or not?
 

·
Premium Member
Joined
·
435 Posts
Discussion Starter #16
I know GM "W" Bodies such as the Oldsmobile Intrigue had a ball valve check valve assembly as part of the filler tube connection at the tank. On this car you couldn't pass a siphon hose down the fuel filler tube, as you couldn't get by this ball check valve.

In the Olds Intrigue there was an access panel to the fuel tank from behind the rear seats, inside the car, and you could drain the tank from there.


firehawk- Did you notice a check valve on the filler assembly near the tank? If I recall Alldata says drain the tank, but doesn't say how.. Therefore I'd assume it would be out the filler tube, but be carefull. If your siphon hose hits resistance, your up against that check valve assembly.. Don't break it.

There's no check ball on our filler neck that I could see *didn't look* BUT what does prevent siphoning is a screen right where the filler tube enters the tank.
 

·
Premium Member
Joined
·
435 Posts
Discussion Starter #17
Thanks for pioneering this! Looking at the photos of the fuel pump assemblies, it looks as though you may be able to remove the black clip from the Eco pump assembly to raise the float or valve. If you get a chance, could you take a look at your original pump and verify if this is true or not?
I don't see any adjustment at all. The float thingey is totally different between the 2 modules. It does look like if you could get your hands on the proper float thingey it would clip right onto the other module. I am willing to bet you cannot buy that piece by itself, you must buy the whole thing. Fortunately used they're not too spendy really and if you look a little bit a low mile one can be found easily since our cars are still fairly new.


The bright side to buying a whole replacement module to do this mod is you'll now have a spare fuel pump, sending unit and tank pressure sensor if any should ever fail.

I don't believe GM sells the pump only, most manufacturers don't anymore but you can take the module apart and swap out just pumps.
 

·
Premium Member
Joined
·
435 Posts
Discussion Starter #18
Next venture: Factory heated mirrors, factory heated seats.
 

·
Premium Member
Joined
·
1,537 Posts
Very nice write-up!

Next venture: Factory heated mirrors, factory heated seats.
The factory heated mirrors is something I've been wanting to do. As long as the Cruze is pre-wired for the heated mirrors, it should be an easy job.
 

·
Premium Member
Joined
·
435 Posts
Discussion Starter #20
Very nice write-up!



The factory heated mirrors is something I've been wanting to do. As long as the Cruze is pre-wired for the heated mirrors, it should be an easy job.
I really need to get a schematic for our cars. Without those I cannot proceed.

Are our heated mirrors just wired into the rear defroster? Are they controlled by the bcm? Are they ran from some kind of door control module? Too many questions that could be easily answered by studying a schematic........
 
1 - 20 of 132 Posts
Top