(Fuel pump) help with fuel pump

[Chameleon 06]

How do I replace the fuel pump on 2006 Chevy avalanche Ltz, is it hard to do or any specific issues ppl have had replacing the fuel pump

 

[Randy]

Lots of members have change their fuel pumps, not too difficult of a job, you two options if you do it yourself.

1. One is to drop the tank and R&R the pump.
2. Cut an access panel in the floor under the rear seat on the drivers side.

Both methods have pros and cons and depends on your skills.. And much, much cheaper that the dealer or most shops. Some have paid over a thousand dollars at the deal for what is really under a 2 hour job if your a tech at a dealer with a lift, knowledge and the correct tools.

I personally went with the access panel method so if I ever when have to change it again it's a 30 min job and could be done on the road if needed..

Measurements for fuel pump access door (PIC INCLUDED!)

So with having to replace my fuel pump yet again and not wanting to pay a shop for labor again, I decided to do the fuel pump access door under the rear seat. This was the 2nd new pump in a year in a half and its cost me a lot to have it replaced twice. Ran fine Wednesday when I went to work...

www.chevyavalanchefanclub.com

 

[Vaeagleav]

I have been lucky so far and have not had to replace the pump in either my 2004 AV (when I owned it) or my 2008 AV yet.
I do agree with Randy in that either method has pros and cons. I am too old and feeble to work on my AV at home in the driveway anymore so I would lean towards taking it to a shop with a lift and mechanics to handle the job. When the original poster has a 15+ year old vehicle it bound to have rust and brittle lines and wires etc. and it also would be a good time to drop tank and inspect a basically hidden area for rust and corrosion and replace or treat areas that need it.
If you use the hole cut method and then something breaks while working there you may not be able to reach and repair things through a small hatch, you would then probably have to tow your AV to a shop to drop the tank anyway. Once hatch is cut you are setting things up for water and gas fume leaks into the cab as well as rust.
Good luck with which ever way you choose.

 

[ygmn]

Now if you have a rusted vehicle in the North it can be a PIA since the rust will ruin the retaining ring and more then likely the mounting ring as well as fuel lines.

 

[Randy]

If you look at the way I did mine the access panel overlaps the opening all the way around by 1 inch and bolts down tight to the sheet metal and sealed with silicone. So structurally sound for those who think the access panel makes the vehicle unsafe and sealed air tight so water, gas or exhaust fumes cannot enter.
For those who live in the belt it also makes it easier to inspect and do regular maintenance since it's and area that's prone to rust and could be very dangerous if the fuel lines rust and leak which has happed to many club members here. If my AV was subject to those conditions I would want to be able to easily check it once a year and clean and coat the area and lines to prevent corrosion.
Your right about having to drop the tank if you suspect the lines or top of the pump housing is rusted. And IMHO, if it were mine I would drop the tank and then cut the access hole to be able to check on it or replace the pump in the future..

 

[Chameleon 06]

If you look at the way I did mine the access panel overlaps the opening all the way around by 1 inch and bolts down tight to the sheet metal and sealed with silicone. So structurally sound for those who think the access panel makes the vehicle unsafe and sealed air tight so water, gas or exhaust fumes cannot enter.
For those who live in the belt it also makes it easier to inspect and do regular maintenance since it's and area that's prone to rust and could be very dangerous if the fuel lines rust and leak which has happed to many club members here. If my AV was subject to those conditions I would want to be able to easily check it once a year and clean and coat the area and lines to prevent corrosion.
Your right about having to drop the tank if you suspect the lines or top of the pump housing is rusted. And IMHO, if it were mine I would drop the tank and then cut the access hole to be able to check on it or replace the pump in the future..

Thank you for the help I dropped the tank took me few hrs cuz of the spare tire in the way haha. But I got put back in n together and it still doesn't start

 

[Randy]

When you turn the key to the first position with out cranking it over do you hear the fuel pump run for a few seconds?? If you do then the fuel pump is most likely working. Next check pressure at the fuel rail, if you have pressure there then it's not anything to do with the fuel system.

I would check for spark next..

If you don't have fuel pressure I would double check the connections, grounds, fuses, fuel pump relay. Also a chance of a bad new fuel pump, there has been a few here that have had the issue (another pro for access panel mod)..

Good luck

 

[Dron]

Dropping the tank it is ese. Empty tank you can drop by you self. I dropped full of fuel tank by myself, with the hydraulic jack. There a lot of videos on YouTube.
For rusted trucks: I'll bay set of plastics fuel lines and adapters from steel to plastic (about $100 and you can return it if not used). Or Dorman stainless steel complete replacement kit ($250). Or have second car to run to nearest auto parts store if needed. It is easy to crack rusted fuel lines. Replacing fuel pump no more than 4 hours for DIY guy, including replacement some cracked fuel lines. Slowly, with beer brakes of course.
One more importing think!
By Acdelco unit. It cost over $260.
Cheap eBay units cost $60.
You can by on eBay just pomp it self for $20-30 (people had good lock with Kemso). And replace only pump, keeping all OEM assembly unit . Going this way, you can avoided the problems I have on my Chevy Express.
Problem with eBay (I have this lock with Pepboys cheap pump) units. The fuel level sensor (sending unit) goes bad after 1000 miles. I replaced 2 pumps on my Express with the same results. Pump is running, fuel level on "0", check engine lite is on- 2 cods for bad sending unit, I drop the tank one more time to check fuel level sensor- it is riveted to plastic base so bad-a lot of play. I fixed (sims like fixed) and several miles down the road-check engine light is ON and fuel level-"0".
I check the gas level by odometer for past several years . Close to 300 miles- time to refuel.
Hope it is helps.

 

[EXT4ME]

This is one repair I refuse to use less than ACDelco OEM parts for.

I have never had a fuel pump go out at a convenient place or time and I prefer to reduce the chances of that happening as much as I can.

 

[Randy]

I installed a Walbro 255L fuel pump which are a quality pump and meets or exceeds the factory pump. I do carry an extra ACDelco pump with me on long trips just in case and I could swap it out on the road. I picked it up on ebay for $50, it's just the pump, filter and fuel line not the complete module.

One of my experiences with having a fuel pump go out go the road was my friends Suburban towing his boat and my family in my AV towing my boat going camping to a lake for a few days. We were in route about 3/4 of the way there and his fuel pump went out, it's Friday about 3:00 PM and we get it towed to dealer and they don't have a pump in stock and won't have one until the next day but it doesn't matter because there won't have techs on Saturday to replace anyway. So we loaded most of their gear in my AV, rented a car (they didn't have a truck that could pull his boat) and we went to the lake for the weekend. Late Sunday we dropped them off at a hotel and they picked up their Suburban Monday afternoon and made it home. Their total cost for the repair $1,200 at the dealer, $75 rental car $200 two rooms for the night..

My pump went out at about 160,000 miles and I was on my way home from work at 5:00PM, 100 degrees outside in stop and go rush hour traffic. All of a sudden it just died and I'm sitting in the middle of 5 lanes of stop and go with people honking at me. I started to get out thinking how I'm I going to get this off the road and I look behind me in traffic a couple of cars back is a tow truck. She pulls up behind me (yes she) and says to get back in and pushes me off the road. I talk to her and she's already on a call but calls on the radio and another rig is on the way.. I have AAA so I get it towed home and put it the driveway. Being on this site since March of 2002 and reading of fuel pump failures and with the story above in my past I knew that sooner or later it's probably going to go out I had already planned to go the access panel route when it did and had picked up the Walbro fuel pump, plus went to a auto dismantler and picked up the sheet metal that is above the fuel pump under the rear passenger seat out of and 2500 AV. The rest is in that link a few posts back..

So, my recommendation is to carry a spare pump just in case, even if you can't change on the road you have the correct pump and have the dealer or other shop change it out..

I have put together a dual pump set up ready to go in when I get a chance or when it goes out again (almost 120,000 miles on this pump). I have already added overhead switches, one that will turn on the second pump if the first goes out.

 

[Dron]

I installed a Walbro 255L fuel pump which are a quality pump and meets or exceeds the factory pump. I do carry an extra ACDelco pump with me on long trips just in case and I could swap it out on the road. I picked it up on ebay for $50, it's just the pump, filter and fuel line not the complete module.

One of my experiences with having a fuel pump go out go the road was my friends Suburban towing his boat and my family in my AV towing my boat going camping to a lake for a few days. We were in route about 3/4 of the way there and his fuel pump went out, it's Friday about 3:00 PM and we get it towed to dealer and they don't have a pump in stock and won't have one until the next day but it doesn't matter because there won't have techs on Saturday to replace anyway. So we loaded most of their gear in my AV, rented a car (they didn't have a truck that could pull his boat) and we went to the lake for the weekend. Late Sunday we dropped them off at a hotel and they picked up their Suburban Monday afternoon and made it home. Their total cost for the repair $1,200 at the dealer, $75 rental car $200 two rooms for the night..

My pump went out at about 160,000 miles and I was on my way home from work at 5:00PM, 100 degrees outside in stop and go rush hour traffic. All of a sudden it just died and I'm sitting in the middle of 5 lanes of stop and go with people honking at me. I started to get out thinking how I'm I going to get this off the road and I look behind me in traffic a couple of cars back is a tow truck. She pulls up behind me (yes she) and says to get back in and pushes me off the road. I talk to her and she's already on a call but calls on the radio and another rig is on the way.. I have AAA so I get it towed home and put it the driveway. Being on this site since March of 2002 and reading of fuel pump failures and with the story above in my past I knew that sooner or later it's probably going to go out I had already planned to go the access panel route when it did and had picked up the Walbro fuel pump, plus went to a auto dismantler and picked up the sheet metal that is above the fuel pump under the rear passenger seat out of and 2500 AV. The rest is in that link a few posts back..

So, my recommendation is to carry a spare pump just in case, even if you can't change on the road you have the correct pump and have the dealer or other shop change it out..

I have put together a dual pump set up ready to go in when I get a chance or when it goes out again (almost 120,000 miles on this pump). I have already added overhead switches, one that will turn on the second pump if the first goes out.

I like that dual setup. That aluminum fitting for a dual pumps looks grate. $500 for this setup +wiring, switches.

 

[Randy]

Thanks, I'll get to it one of these days.. It all plugs into the factory wiring harness, no cutting or splicing, if both pumps went out or you wanted to return it to stock you just pull the them out, drop in a factory fuel pump model, plug in the factory connector and drive away.

The harness has 40 amp relays with larger wires to handle more amps from the high output pumps, connects directly to alternator so there is little or no voltage drop to the pumps. It's part of future performance mods for the motor that keeps getting pushed out..

 

[Wpolonavyguy]

If you look at the way I did mine the access panel overlaps the opening all the way around by 1 inch and bolts down tight to the sheet metal and sealed with silicone. So structurally sound for those who think the access panel makes the vehicle unsafe and sealed air tight so water, gas or exhaust fumes cannot enter.
For those who live in the belt it also makes it easier to inspect and do regular maintenance since it's and area that's prone to rust and could be very dangerous if the fuel lines rust and leak which has happed to many club members here. If my AV was subject to those conditions I would want to be able to easily check it once a year and clean and coat the area and lines to prevent corrosion.
Your right about having to drop the tank if you suspect the lines or top of the pump housing is rusted. And IMHO, if it were mine I would drop the tank and then cut the access hole to be able to check on it or replace the pump in the future..

I did similar on my 07. Here's pictures of my access hole under seat.

 

[Wpolonavyguy]

The pump wasn't match like Amazon said, I left the plastic plug & tried flex seal tape.
Didn't work gas desolved the tape & air leaked in. Instead of dropping tank again figured making access door was best way to go. The rubber plug & hose clamp I should have done but was in hurry & tired forgot only rubber resists fuel.
I also think investing in a ring lock tool to use as hammer & brass pin don't fit well.

 

[SpottyJ]

Why is it that one of the ends on the replacemnt fuel pump needs to be plugged (hose clamped)? Would think there would not be an extra fitting that needed to be plugged.

 

[redheadedrod]

Why is it that one of the ends on the replacemnt fuel pump needs to be plugged (hose clamped)? Would think there would not be an extra fitting that needed to be plugged.

2003 for sure was a "return" style fuel system. I was told the 2004 model year they switched to a non-return fuel system. But the 6.0 engine I got from a 2005 escalade looks exactly like my 2003. Basically if you didn't have the fuel filter on the frame rail under your drivers door next to the ABS module you did not have the fuel return system. The difference is the Fuel return system uses all three of those lines. The non return fuel system only uses two of those 3 lines. 1 line is the fuel feed line, 1 line is the vent canister line and the other is the fuel return line (If equipped). I would be careful with what you cap the other line with and make sure it is compatible with gasoline. Not all "rubber" caps are since they are normally for vacuum lines.

So if you got the 3 line pump instead of a 2 line pump it will work but you need to cap off the unused return line.

 

[redheadedrod]

I installed a Walbro 255L fuel pump which are a quality pump and meets or exceeds the factory pump. I do carry an extra ACDelco pump with me on long trips just in case and I could swap it out on the road. I picked it up on ebay for $50, it's just the pump, filter and fuel line not the complete module.

One of my experiences with having a fuel pump go out go the road was my friends Suburban towing his boat and my family in my AV towing my boat going camping to a lake for a few days. We were in route about 3/4 of the way there and his fuel pump went out, it's Friday about 3:00 PM and we get it towed to dealer and they don't have a pump in stock and won't have one until the next day but it doesn't matter because there won't have techs on Saturday to replace anyway. So we loaded most of their gear in my AV, rented a car (they didn't have a truck that could pull his boat) and we went to the lake for the weekend. Late Sunday we dropped them off at a hotel and they picked up their Suburban Monday afternoon and made it home. Their total cost for the repair $1,200 at the dealer, $75 rental car $200 two rooms for the night..

My pump went out at about 160,000 miles and I was on my way home from work at 5:00PM, 100 degrees outside in stop and go rush hour traffic. All of a sudden it just died and I'm sitting in the middle of 5 lanes of stop and go with people honking at me. I started to get out thinking how I'm I going to get this off the road and I look behind me in traffic a couple of cars back is a tow truck. She pulls up behind me (yes she) and says to get back in and pushes me off the road. I talk to her and she's already on a call but calls on the radio and another rig is on the way.. I have AAA so I get it towed home and put it the driveway. Being on this site since March of 2002 and reading of fuel pump failures and with the story above in my past I knew that sooner or later it's probably going to go out I had already planned to go the access panel route when it did and had picked up the Walbro fuel pump, plus went to a auto dismantler and picked up the sheet metal that is above the fuel pump under the rear passenger seat out of and 2500 AV. The rest is in that link a few posts back..

So, my recommendation is to carry a spare pump just in case, even if you can't change on the road you have the correct pump and have the dealer or other shop change it out..

I have put together a dual pump set up ready to go in when I get a chance or when it goes out again (almost 120,000 miles on this pump). I have already added overhead switches, one that will turn on the second pump if the first goes out.

Hey Randy, where you get that dual pump canister? I need one of those for my truck. I will likley be using I believe it is dual 535 Walbro pumps for my truck. May be able to "get by" with one but will likely put two in my truck. Will start out with a Eaton M122 blower on my truck first which should put out 600-700hp but eventually move to a Eddlebrock 2650 that will push 1000hp or more. Have a lot of upgrades to do before I go with the Eddlebrock.

 

[Randy]

You will defiantly need two, one primary and then a secondary pump controlled with a pressure switch so at low speed or just cruising when you don't need max fuel flow only pump 1 is on, then as boost increases pump 2 comes on to meet demand and so don't go lean.

They didn't have exactly what I wanted so I bought the dual pump bare pump kit and two hot wire kits and reworked them for how I wanted it to work.

Design, Manufacturing and Distribution Parts for Performance Automotive Solutions

Design, Manufacturing and Distribution Parts for Performance Automotive Solutions

www.racetronix.biz

 

[redheadedrod]

I wonder if this wireharness for a CTS-V I picked up when I bought some stuff would work for a 2 pump setup... Will have to do more research.
Of course now I have spent like 30 minutes looking on their site.

I need fuel injectors, fuel line and more pump...

Wondering if these trucks have low or high impedance injectors. The fuel system is probably the one area I am the most weakest at knowledge wise.

 

[Randy]

Most are high impedance and just need to give the specs to the tuner. If it's a fuel pump wiring harness and has 2 relays then it may work. If not Racetronix has universal dual pump harnesses, you just need to match the connector on the stock harness to if you want to just plug it in with no splicing. You will probably have to do a bit of custom wiring, they have all types of Weatherpack connectors used on GM fuel systems, very easy to do.

 

[redheadedrod]

Most are high impedance and just need to give the specs to the tuner. If it's a fuel pump wiring harness and has 2 relays then it may work. If not Racetronix has universal dual pump harnesses, you just need to match the connector on the stock harness to if you want to just plug it in with no splicing. You will probably have to do a bit of custom wiring, they have all types of Weatherpack connectors used on GM fuel systems, very easy to do.

Yea I saw the dual pump setups. Those look like they would work well. I take it they just replace the factory pump and you use the original basket and such? Do you need to drill a hole in the top for the new fuel lines since I am sure the ones on there now won't be big enough. I am likely going to run AN8 hose I guess from the tank and back. I assume there will be some sort of adapter I will need up front as well. I have some STS-V blowers that are essentially Eaton M122 blowers. I will look at picking up a case and just swapping the parts over from one to the new case and use that with the adapter kit I can get for about $1800 and a magnuson tub. Will be a cheap way to a blower to get me over 600hp.

Fitting that on an LQ9 that has been rebuilt with forged pistons and all the trimmings. Running a 408 stroker kit in it and a BTR stage 3 blower cam, CNC ported 799 heads, double springs and larger intake valves. Should be a beast. Looking for a transmission and TC to put behind it now. I will likely get 4l80E and push button transfer case from a 3/4 ton SUV then have them gone through so I have no issues with them. I MAY end up moving up to an Edlebrock 2650 blower in the future. Will just require the blower and a new adapter plate. And a new tune I am sure.

 

[Randy]

Yes, you have to do a little fabrication with the float and attaching it to the top plate unless you buy one of the complete setups but there's no way to tell if the top would fit opening our tanks. I bought a $50 complete pump assembly and modified it to hold the dual pumps. Hardest part was adding the bulkhead for the second pump, now they have a bulkhead with 6 wires so you can just use the original opening.

 

[redheadedrod]

Ok, but what about the fuel lines? The one they show on that site have both of them go up to an AN fitting in a Y. Did you just use the three lines somehow instead? I know in the '03 one is a feed, one is return and the third is vent line. The pump and lines in my truck now are a little over a year old so I know its all still pretty new. And doing it this way is a lot cheaper than paying someone $1000 to make a drop in one for you.

 

[Randy]

This the one I used with red anodized aluminum Y with a brass barbed fitting on top that slips over the fuel pumps to combine them. Then one of the plastic feed tubes to the single fuel line outlet which then attaches to the stock fuel line.

Also, my 02 is the sounds the same configuration as yours 3/8 fuel line, 5/16 return line and a 3/8 vent..

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Purchase Dual Pump Assembly 510LPH+, E85 or shop other Dual Pump Systems (Complete) and Racetronix products.

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[redheadedrod]

Ahh ok, the one I was looking at apparently wasn't like that. Which of the "kits" Did you get? I see they have the fuel pressure switch as part of it. Assume that goes on the test port on the fuel line? And I assume basically the switch is probably set for like 50psi and it will turn on the second pump if the pressure drops below 50PSI to keep it up?

Can you just go straight to the larger line such as the AN8 or AN6 lines from the factory output or is that going to require a further modification of the pump assembly?

If I put a SC on this engine up front i will likely add the whole shebang at the same time but would require me to be able to go with the larger lines.

I have never done a fuel system upgrade like this so I would like to hear about all of what I need to do.
Thank you for your time.

Might also do the upgraded pumps for the $20 more.