I could really use some ideas on a problem I’m having with my 09’ LX570 w/ 166k miles.
Short version: fuel sending unit was giving false readings at the bottom of the tank but the truck was running fine. The sending unit was replaced along with the fuel pump. ~30 miles later it throws a P0171 and P0174 code. 50 miles later it loses fuel pressure and dies. The fuel pump is re-replaced and it does the same thing again. Fuel ECU replaced: same problem, pump reinstalled: same problem, relays replaced: same problem. All parts were OEM Toyota.
Any ideas on what might be going on?
Long Version: The LX was running and driving totally fine but I ran it out of gas a couple of times while the gauge showed between 1/8 and 1/4 tank of fuel. It’s a semi common problem that the sending units go bad in these trucks so I ordered a new one along with the fuel pump (“while I’m in there”) and seals from Toyota. All the parts were OEM Toyota/Lexus parts.
I was going to do the work myself but once I looked into it a little further and realized it called for dropping the tank and a couple of SST’s I decided to just let a friend that owns a certified Toyota shop do the work.
They do the work in a few hours and I get it back. Everything seems fine at first but about 30 miles after the repair I get a P0171 and a P0174 CEL. The LX was running fine so I figured I’d check it out once I got home. Well 50 miles later I notice it starts hesitating and then I’m dead in the water....10 miles outside cell coverage, offroad in a National Forrest with my family and no supplies.
9 hours later, some hitchhiking, a drunk Bigfoot hunter, some luck and a helpful friend...I drag it back to the shop on a trailer.
The next day they check it out and it only has about 10 psi of fuel pressure and they think the new OEM Toyota fuel pump is bad. They replace the pump, the LX runs fine again and the exact same thing happens at the same mileage. P0171/P0174 and eventual death around 50 miles. This time I deliberately stayed close to home so it got a rollback ride from by driveway back to the shop.
Now...what the heck is going on? It’s losing fuel pressure somehow but the pump is properly installed (allegedly) but they’ve had it in and out several times now. They’ve replaced the fuel pump ECU, fuel pump, sending unit, relay, and really everything else that might cause this. The LX is still not getting fuel and the shop is out of ideas. If any of you cruiser guru’s out there have any advice, I’d love to hear it. We’re kind of grasping at straws at this point.
Thanks in advance and sorry for the long read if anyone actually read it all.
Short version: fuel sending unit was giving false readings at the bottom of the tank but the truck was running fine. The sending unit was replaced along with the fuel pump. ~30 miles later it throws a P0171 and P0174 code. 50 miles later it loses fuel pressure and dies. The fuel pump is re-replaced and it does the same thing again. Fuel ECU replaced: same problem, pump reinstalled: same problem, relays replaced: same problem. All parts were OEM Toyota.
Any ideas on what might be going on?
Long Version: The LX was running and driving totally fine but I ran it out of gas a couple of times while the gauge showed between 1/8 and 1/4 tank of fuel. It’s a semi common problem that the sending units go bad in these trucks so I ordered a new one along with the fuel pump (“while I’m in there”) and seals from Toyota. All the parts were OEM Toyota/Lexus parts.
I was going to do the work myself but once I looked into it a little further and realized it called for dropping the tank and a couple of SST’s I decided to just let a friend that owns a certified Toyota shop do the work.
They do the work in a few hours and I get it back. Everything seems fine at first but about 30 miles after the repair I get a P0171 and a P0174 CEL. The LX was running fine so I figured I’d check it out once I got home. Well 50 miles later I notice it starts hesitating and then I’m dead in the water....10 miles outside cell coverage, offroad in a National Forrest with my family and no supplies.
9 hours later, some hitchhiking, a drunk Bigfoot hunter, some luck and a helpful friend...I drag it back to the shop on a trailer.
The next day they check it out and it only has about 10 psi of fuel pressure and they think the new OEM Toyota fuel pump is bad. They replace the pump, the LX runs fine again and the exact same thing happens at the same mileage. P0171/P0174 and eventual death around 50 miles. This time I deliberately stayed close to home so it got a rollback ride from by driveway back to the shop.
Now...what the heck is going on? It’s losing fuel pressure somehow but the pump is properly installed (allegedly) but they’ve had it in and out several times now. They’ve replaced the fuel pump ECU, fuel pump, sending unit, relay, and really everything else that might cause this. The LX is still not getting fuel and the shop is out of ideas. If any of you cruiser guru’s out there have any advice, I’d love to hear it. We’re kind of grasping at straws at this point.
Thanks in advance and sorry for the long read if anyone actually read it all.
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