DIY Fuel Pump Replace (1 Viewer)

[TeCKis300]

Replaced a fuel pump recently as part of resolving an idle fuel pressure issue. Diagnostic thread here:

P0171: System too Lean (Fuel Trim)

Working through this and could use the hive minds support. P0171: System too Lean (Fuel Trim). Also P0300: Random/mulitple Cylinder misfire detected. Multiple specific cylinder misfires P030x. Symptoms: In diagnostics after getting home. LT fuel trim on both banks at idle are high. +15 and...

forum.ih8mud.com

Didn't find much documentation on this site so here's my attempt for future reference.

Couple strategies to do this. From above through the cabin access hatch, or below via dropping the tank. Having done this, dropping the tank is the way to go. Avoids cutting the body to enlarge the access hole. Then inevitable fight with the tight retention ring. Quicker and easier, albeit messier and working in a more uncomfortable position. Roughly a 2-4 hr operation, or 3 out of 5 banana job. Run fuel down ~0 mile range, leaving about 3-4 gallons to make dropping easier.

Parts (please check for year compatibility)​

23220-50271 Fuel Pump ~$290
77169-02050 Fuel Pump Assembly o-ring ~$7
Options:
83320-60580 Fuel level Sender ~$140
77020-60342 Fuel Pump Assembly ~$451 (Recommend for incrementally more, just replace the whole assembly which includes fuel level sender which has been known to go out on occasion)
77144-04010 Fuel Pump Retainer Ring ~$42

References:​

Tools:​

1. Tall jack stands (6-ton)
2. 12 and 14mm socket
3. Fuel pump lid/ring removal tool. Or hammer and dull chisel/metal bar
4. Shop vac or air compressor
5. Floor jack

Steps:​

1. Discharge fuel pressure
   1. Remove C/OPN Relay in engine bay relay block
   2. Crank over engine to bleed off pressure
2. Remove Fuel Tank skid
   1. 5x 14mm bolts
3. Prepare Fuel Tank for Removal (reference video)
   1. Remove 2x forward lines: fuel pump feed and return line alongside tank. Held together by plastic retainers that pops out easily by hand or gentle pressure with a flat blade
   2. 
      
   3. Remove 3x rearward lines: large diameter tank fill (10mm hose clamp), fill breather (pop up brown retainer, and squeeze side button fuel connector) , evap canister breather (pop up green clip). Remove from body retainers
      
4. Drop tank - supported by floor jack, transmission jack, or the like. Not very heavy, but needs to be supported to control drop to undo fuel tank harness
   1. Remove two straps. 2x 12mm bolts. Remove retaining clip and pin. Remove straps
   2. Drop tank ~10". Reach up and around tank, right behind trailer arm link on frame, to unclip harness (reference video)
   3. Drop tank completely out. Guide rearward lines.
      
5. Clean top of fuel tank before opening pump assembly. Recommend a shop vac with brush head
6. Remove 2x lines from pump assembly cover. Cover ports.
7. Open pump assembly
   1. Mark retaining ring position. (You'll need to tighten back or almost back to this position)
   2. Use fancy ring removal tool. Or old school hammer to gently tap tap, reposition 180* tap tap, repeat. Gentle taps and potentially hundreds of taps so as not to break ring. It'll only give a mm at a time, and need to turn ~180 degrees for it to loosen up enough to turn. Don't count on it turning full circles with any tap. Patience.
      
   3. Note 4 safety catches that needs to be depressed when opening
8. Solve jigsaw puzzle to disassemble housing.

 

[grinchy]

A note on the evap line clips (green vertical clips) - only loosen to halfway. If you push the clip further one of the legs will break. I was unable to find just the clip available for resale.

 

[CharlieS]

Excellent write up. I've only been in there from the top, but wonder if it might be worthwhile to go in via to top to disconnect wire harness and lines that are accessible there?

Also, the tool for removing those locking rings isn't super expensive. I have one from when I rode bmw adventure bikes; they use the same arrangement. I think the tool was under $20. The hammer and chisel does the job, but the tool spreads the force well and reduces the likelihood of breaking fins on the lock ring.

 

[TeCKis300]

Excellent write up. I've only been in there from the top, but wonder if it might be worthwhile to go in via to top to disconnect wire harness and lines that are accessible there?

Also, the tool for removing those locking rings isn't super expensive. I have one from when I rode bmw adventure bikes; they use the same arrangement. I think the tool was under $20. The hammer and chisel does the job, but the tool spreads the force well and reduces the likelihood of breaking fins on the lock ring.

View attachment 3082316

Curious how long it takes to remove the interior pieces to get at the access cover?

The time to do that is what discouraged me. From the bottom, it's 7 bolts, 5 lines, and 1 plug, all readily reachable. 30 minutes if I were to do it again.

There's no need to remove the fuel lines from the access hatch prior to dropping the tank. The fuel line pigtails come down with the tank. Unclipping the harness plug blind wasn't too bad either thanks to the reference video. Ample slack and space to reach in to squeeze the plug release from below.

For the tool, I would recommend it's worth the $20, easily found on Amazon. I thought I could get away without it having done fuel pumps on a couple other cars before (this access ring is on TIGHT). At the same time, I hate single use tools and figure I could cobble or fabricate something together. To your point, the single fins on the ring can be brittle so it would be important to spread the torque load with a proper tool.

 

[isthatalexus]

Update: I dropped the main tank, installed the new fuel pump (full assembly, per recommendation), cleaned everything up, dropped the 24 gal. LRA, corrected all of the issues of the original install from that hack-job done in Atlanta (cut body brackets, properly route CC filter, etc.), and put everything back together.

The lean codes are gone, and fuel consumption appears to be getting better as ST FTs beat the LT FTs back into submission (read: return to stoichiometry); getting negative STs and LTs are back in single digits. Positive.

After buttoning up the fuel system, I reconnected the battery after ~3 days of being disconnected. My assumption was that codes would be cleared by then due to hard reset and enough time for capacitors to discharge. Start truck and test drive to find all kinds of blinking MILs (TRAC, VSC, 4LO-flashing, and CEL), so use Techstream to investigate. Findings: P043E, P043F, P2401, P2402, P2419. Let sit overnight, but same thing in AM. Dropped the LRA again and re-tightened and confirmed all connections, including cleaning all CC electrical connections. (at CC as well as at bumper plug). I did find that I may have not properly seated the large inbound vent hose from main tank to the CC, which was the likely cause for the five codes in this paragraph. Reassembled.

Test drove truck around the block after letting sit overnight to give it time to vacuum self-test. At this point I still have the MILs mentioned above, none of the Ps from above, but now getting P0453; first time for that one. Called LRA and confirmed all my routing with Aidan (very helpful guy). Also conducted the Techstream VSV self-test, which audibly boosted RPM while active, kind of like the ramp-and-return you hear at normal start...at least mine does this. FWIW, I thought the idle was elevated for too long after startup, at this point, but that may be LT FT still coming down. For the sake of completeness: I am running a two month-old gas cap and I have thoroughly cleaned both cap and filler neck opening.

My next move (I think) is to once again pull main tank and double confirm all connections. I admit to having overlooked installing the new main tank o-ring, which I may replace when I do this. Although, given that P0453 indicates high pressure in main tank, I sincerely doubt that this is necessary or part of the issue.

Questions:

• I've read that P0453 may just 'go away.' Has anyone here observed that in the wild? (maybe I wait a few days/miles before more action)
• While main tank is out again, is there a procedure to test connectivity integrity to the CC? (chase the wire-problem possibility)
• If no wire or install issues are found, do I just brute force this and R&R the CC? (the traditional 'throw parts at problem' approach, but this time including pulling the LRA uh-gain)
• Is there a way to test the pressure sensor in the CC? If that is fouled, then it could be the culprit. Could also be the internals of the CC, but I did not get that impression based on my bench tests. (checking flow by blowing into CC while holding closed certain holes, per procedure in some other post)
• Techstream always shows a notice about engine calibration with the numbers 360C2600 and A0C01000. Is that engine firmware, and does that have to be updated by a mechanic/dealer with official Techstream?
• Anyone see my blind spot(s) and wish to share them with me?

As always, @TeCKis300 (and rest of gang) thank you for the subbort here. Much appreciate.

 

[AnyMal]

Update: I dropped the main tank, installed the new fuel pump (full assembly, per recommendation), cleaned everything up, dropped the 24 gal. LRA, corrected all of the issues of the original install from that hack-job done in Atlanta (cut body brackets, properly route CC filter, etc.), and put everything back together.

The lean codes are gone, and fuel consumption appears to be getting better as ST FTs beat the LT FTs back into submission (read: return to stoichiometry); getting negative STs and LTs are back in single digits. Positive.

After buttoning up the fuel system, I reconnected the battery after ~3 days of being disconnected. My assumption was that codes would be cleared by then due to hard reset and enough time for capacitors to discharge. Start truck and test drive to find all kinds of blinking MILs (TRAC, VSC, 4LO-flashing, and CEL), so use Techstream to investigate. Findings: P043E, P043F, P2401, P2402, P2419. Let sit overnight, but same thing in AM. Dropped the LRA again and re-tightened and confirmed all connections, including cleaning all CC electrical connections. (at CC as well as at bumper plug). I did find that I may have not properly seated the large inbound vent hose from main tank to the CC, which was the likely cause for the five codes in this paragraph. Reassembled.

Test drove truck around the block after letting sit overnight to give it time to vacuum self-test. At this point I still have the MILs mentioned above, none of the Ps from above, but now getting P0453; first time for that one. Called LRA and confirmed all my routing with Aidan (very helpful guy). Also conducted the Techstream VSV self-test, which audibly boosted RPM while active, kind of like the ramp-and-return you hear at normal start...at least mine does this. FWIW, I thought the idle was elevated for too long after startup, at this point, but that may be LT FT still coming down. For the sake of completeness: I am running a two month-old gas cap and I have thoroughly cleaned both cap and filler neck opening.

My next move (I think) is to once again pull main tank and double confirm all connections. I admit to having overlooked installing the new main tank o-ring, which I may replace when I do this. Although, given that P0453 indicates high pressure in main tank, I sincerely doubt that this is necessary or part of the issue.

Questions:

• I've read that P0453 may just 'go away.' Has anyone here observed that in the wild? (maybe I wait a few days/miles before more action)
• While main tank is out again, is there a procedure to test connectivity integrity to the CC? (chase the wire-problem possibility)
• If no wire or install issues are found, do I just brute force this and R&R the CC? (the traditional 'throw parts at problem' approach, but this time including pulling the LRA uh-gain)
• Is there a way to test the pressure sensor in the CC? If that is fouled, then it could be the culprit. Could also be the internals of the CC, but I did not get that impression based on my bench tests. (checking flow by blowing into CC while holding closed certain holes, per procedure in some other post)
• Techstream always shows a notice about engine calibration with the numbers 360C2600 and A0C01000. Is that engine firmware, and does that have to be updated by a mechanic/dealer with official Techstream?
• Anyone see my blind spot(s) and wish to share them with me?

As always, @TeCKis300 (and rest of gang) thank you for the subbort here. Much appreciate.

Im not qualified to comment on the codes necessarily but i do know that certain “hard” codes have to be cleared manually via tech-stream or scan tool. I know its dumb but im assuming you have done this?

 

[isthatalexus]

Im not qualified to comment on the codes necessarily but i do know that certain “hard” codes have to be cleared manually via tech-stream or scan tool. I know its dumb but im assuming you have done this?

I've performed two TS 'eraser' procedures, but I'll do so again.

My next move is to drop the aux tank again to check the on-tank wiring which serves the CC. I have a suspicion that some portion of the small wires might have chafing damage inside of the protective harness sleeve. I've seen this issue elsewhere with a poorly installed LRA.

Either way, thank you for chiming in.

 

[TeCKis300]

Update: I dropped the main tank, installed the new fuel pump (full assembly, per recommendation), cleaned everything up, dropped the 24 gal. LRA, corrected all of the issues of the original install from that hack-job done in Atlanta (cut body brackets, properly route CC filter, etc.), and put everything back together.

The lean codes are gone, and fuel consumption appears to be getting better as ST FTs beat the LT FTs back into submission (read: return to stoichiometry); getting negative STs and LTs are back in single digits. Positive.

After buttoning up the fuel system, I reconnected the battery after ~3 days of being disconnected. My assumption was that codes would be cleared by then due to hard reset and enough time for capacitors to discharge. Start truck and test drive to find all kinds of blinking MILs (TRAC, VSC, 4LO-flashing, and CEL), so use Techstream to investigate. Findings: P043E, P043F, P2401, P2402, P2419. Let sit overnight, but same thing in AM. Dropped the LRA again and re-tightened and confirmed all connections, including cleaning all CC electrical connections. (at CC as well as at bumper plug). I did find that I may have not properly seated the large inbound vent hose from main tank to the CC, which was the likely cause for the five codes in this paragraph. Reassembled.

Test drove truck around the block after letting sit overnight to give it time to vacuum self-test. At this point I still have the MILs mentioned above, none of the Ps from above, but now getting P0453; first time for that one. Called LRA and confirmed all my routing with Aidan (very helpful guy). Also conducted the Techstream VSV self-test, which audibly boosted RPM while active, kind of like the ramp-and-return you hear at normal start...at least mine does this. FWIW, I thought the idle was elevated for too long after startup, at this point, but that may be LT FT still coming down. For the sake of completeness: I am running a two month-old gas cap and I have thoroughly cleaned both cap and filler neck opening.

My next move (I think) is to once again pull main tank and double confirm all connections. I admit to having overlooked installing the new main tank o-ring, which I may replace when I do this. Although, given that P0453 indicates high pressure in main tank, I sincerely doubt that this is necessary or part of the issue.

Questions:

• I've read that P0453 may just 'go away.' Has anyone here observed that in the wild? (maybe I wait a few days/miles before more action)
• While main tank is out again, is there a procedure to test connectivity integrity to the CC? (chase the wire-problem possibility)
• If no wire or install issues are found, do I just brute force this and R&R the CC? (the traditional 'throw parts at problem' approach, but this time including pulling the LRA uh-gain)
• Is there a way to test the pressure sensor in the CC? If that is fouled, then it could be the culprit. Could also be the internals of the CC, but I did not get that impression based on my bench tests. (checking flow by blowing into CC while holding closed certain holes, per procedure in some other post)
• Techstream always shows a notice about engine calibration with the numbers 360C2600 and A0C01000. Is that engine firmware, and does that have to be updated by a mechanic/dealer with official Techstream?
• Anyone see my blind spot(s) and wish to share them with me?

As always, @TeCKis300 (and rest of gang) thank you for the subbort here. Much appreciate.

P0453 is not one I've dealt with before. So take my comments with a grain of salt.

These would be my suspicions

1. Sensor or wiring to sensor malfunction. You can use a scan gauge on OBD-II to read the output to understand if this is possibly failing high? Referencing a snap of my OBD Fusion monitor, my Vapor Pressure (calculated) reading is 29 inHg. I believe the system is testing for pressure during the nightime test cycle or after cold startup.
2. Check that the vent link isn't kinked

 

[isthatalexus]

P0453 is not one I've dealt with before. So take my comments with a grain of salt.

These would be my suspicions

1. Sensor or wiring to sensor malfunction. You can use a scan gauge on OBD-II to read the output to understand if this is possibly failing high? Referencing a snap of my OBD Fusion monitor, my Vapor Pressure (calculated) reading is 29 inHg. I believe the system is testing for pressure during the nightime test cycle or after cold startup.
2. Check that the vent link isn't kinked

I'm showing 26 inHg in most recent run. What I've always found odd: 'Atmosphere Pressure' shows as -2 psi. This figure has been negative for as long as I've been running Dx via Techstream. Your 29 inHg lines up nicely with atm at sea level. I wonder if my negative atm correlates to lower Vapor Pressure. Something is still amiss.

I'm going to check the harness going to the CC again. Maybe that was internally insulted as a result of LRA rubbing for years. I'll also bench the CC again. Vent is no kinked; verified with USB wire camera during and post (re)reinstall.

 

[isthatalexus]

Well, it's day three after re-installing the LRA after doing a harness extension for the charcoal canister. CC wires were distressed, but not unsheathed. It did feel like at least one had an internal break of some kind. (note, see my other posts about how the mal-installed LRA pinched the CC harness/loom)

No dash lights and no codes. Hoooo-freaking-rayyy!

Question: how long does it typically take to re-learn fuel maps? Truck fires up just fine, but idles for a while between 1000 and 1500 RPM for what seems (subjective) too long. Once driven, even for a short distance, the idle RPM goes back into the mid-three-digit neighborhood. It does seem like MPG is still crazy low, particularly while stopped at traffic lights, but I have not driven more than 10 miles yet. My plan is to fill up main and LRA tanks, and put a few hundred miles of mixed driving on.

Observations: shifting appears to be MUCH smoother. Granted, I'm geared 4.88 but running 285/70/17, which makes the truck pretty zippy anyway...but shifting feels better than before replacing weakening fuel pump and repairing damaged CC harness wires.

 

[TeCKis300]

Well, it's day three after re-installing the LRA after doing a harness extension for the charcoal canister. CC wires were distressed, but not unsheathed. It did feel like at least one had an internal break of some kind. (note, see my other posts about how the mal-installed LRA pinched the CC harness/loom)

No dash lights and no codes. Hoooo-freaking-rayyy!

Question: how long does it typically take to re-learn fuel maps? Truck fires up just fine, but idles for a while between 1000 and 1500 RPM for what seems (subjective) too long. Once driven, even for a short distance, the idle RPM goes back into the mid-three-digit neighborhood. It does seem like MPG is still crazy low, particularly while stopped at traffic lights, but I have not driven more than 10 miles yet. My plan is to fill up main and LRA tanks, and put a few hundred miles of mixed driving on.

Observations: shifting appears to be MUCH smoother. Granted, I'm geared 4.88 but running 285/70/17, which makes the truck pretty zippy anyway...but shifting feels better than before replacing weakening fuel pump and repairing damaged CC harness wires.

Good to hear you're making progress!

Learning is pretty quick. Once in closed loop, the short term trims will take effect immediately to get to stoich or target A/F ratios. With learned long term fuel trims taking effect not long after with to offset some of the short term trims.

The elevated idle will generally correspond to open loop, or until the coolant thermostat shows its warm enough to enter closed loops fueling. As it's winter, not unexpected that it's taking longer to warm up with the elevated idle. MPGs probably are low as it's taking relatively more fuel to start and idle in colder temps, to compensate for fuels lower vapor pressure.

 

[isthatalexus]

Good to hear you're making progress!

Learning is pretty quick. Once in closed loop, the short term trims will take effect immediately to get to stoich or target A/F ratios. With learned long term fuel trims taking effect not long after with to offset some of the short term trims.

The elevated idle will generally correspond to open loop, or until the coolant thermostat shows its warm enough to enter closed loops fueling. As it's winter, not unexpected that it's taking longer to warm up with the elevated idle. MPGs probably are low as it's taking relatively more fuel to start and idle in colder temps, to compensate for fuels lower vapor pressure.

thank you friend knowledge/morale power!

 

[bloc]

I did this the other day. Not much to add, other than the $22 "toyota fuel tank lid wrench" I got on amazon worked perfectly. I didn't even need to disconnect the lines from the top of the fuel pump module, thereby avoiding any risk of o-ring issues there.

It took about two hours, with approx 10-gallons of fuel in the tank, and me thinking I didn't need the jack to support the tank. I will admit I didn't respect the physical challenge 65lb of sloshing fuel would present.. which is dumb because I've been absolutely humbled working out with a 2-gallon "slosh pipe" before.. but.. it's done.