Engine shutting off during long trips. (1 Viewer)
- Thread starter 1meancruiser
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I wouldn't believe they switched. Those numbers are temp dependent, there are supplier tolerances, manufacturing differences, porbably even different acceptable brands. As long at it's at 1 or close to 1ohm it's good. Spec is 1ohm or less
unless it exploded, It shouldn't strand you.
voltage at the pump- IF my car was dying while driving i'd run some leads and test at heavy and no load. IF it's close to but not at alternator voltage I'd wonder why. no so great wiring? not great ground, I wonder what the output voltage at the ecu is. It would be good to compare output there and input at the pump.
I don't know if techstream will display pump voltage in their hi/low operating active test. It would be very beneficial if they would just say, when operating under heavy load the voltage at the pump is spec @ 13.5 volts, when at idle speed and no load conditions, the spec should be XX. volts.
they don't though. It should be full, but who knows.
If the fuel pump model # changed mid 06 and all of 07 yet this just happened on a cherry 07-it's probably not the fuel pump, right? You would think if the "new" pump is still having these issues that it's got to be some else. Has anyone who wrapped their fuel lines been able to replicate the issue yet?
it's a mistake to think any fuel pump should be at spec after 13 years. AND it's 100$ lol. cheap mofos. Even cheaper than your 13 year old radiator that isn't in spec either.
The true way to measure volume and pressure is in the book. No one wants to do that, it's just easier to buy a pump and install it.
Don't displace an injector for a volume test on a 100$ pump.
The true way to measure volume and pressure is in the book. No one wants to do that, it's just easier to buy a pump and install it.
Don't displace an injector for a volume test on a 100$ pump.
The 2UZ-fe VVT (06-07) did get a small pump than previous years. I don't know about a fuel pump change or if so why, in the VVT (06-07).
But I can say I've replaced a fuel pump in a 07LX MFD date 10/06. It corrected the issue of stalling (some call vapor lock, which it was not). I also cleaned up the battery cable and wire block, which had a ton of battery acid crusty buildup. Which crusty buildup, increase resistance in wires.
These pumps seem to be weak. That when resistance high in wiring to the pump, combined with the weakness, reduces flow in the low speed of pump. Heat like during a hot day and coupled with running pump in high speed (higher engine RPM, like when pulling/driving up a hill (heating pump)). Than dropping back to low speed (low engine RPM). The pump fails to delivery adquet fuel to engine, in it's low speed.
If running scans at the time engine stalls. We sometime see lean bank 1 & 2 DTC, as engine shuts down
But I can say I've replaced a fuel pump in a 07LX MFD date 10/06. It corrected the issue of stalling (some call vapor lock, which it was not). I also cleaned up the battery cable and wire block, which had a ton of battery acid crusty buildup. Which crusty buildup, increase resistance in wires.
These pumps seem to be weak. That when resistance high in wiring to the pump, combined with the weakness, reduces flow in the low speed of pump. Heat like during a hot day and coupled with running pump in high speed (higher engine RPM, like when pulling/driving up a hill (heating pump)). Than dropping back to low speed (low engine RPM). The pump fails to delivery adquet fuel to engine, in it's low speed.
If running scans at the time engine stalls. We sometime see lean bank 1 & 2 DTC, as engine shuts down
Would jumping the resistor not be a simple emergency fix - and also proof a weak fuel pump if symptoms disappear? It would also increase the return flow and keep the fuel manifold (edit: fuel rail) temperatures lower on hot days.
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if you drive around with the carpet up you can hear the pump cycle. Yes I'd ground the resistor, but I'm sure that will trigger a code.
You could also move the pump ground, and relocate the pump positive if you're thinking (rightly so) that there's no way you're getting alternator voltage at this pump.
Much drama about this on supra boards from long ago.
Thing is, this pump is probably 200% adequate for this job. Checking real voltage at the connector would be a good thing (while driving open loop 80mph on the freeway)
Paul has probably, maybe, watched this pump run out an open tank?
I have on accident. Ten 20 year old frat kids couldn't drink beer that fast.
You could also move the pump ground, and relocate the pump positive if you're thinking (rightly so) that there's no way you're getting alternator voltage at this pump.
Much drama about this on supra boards from long ago.
Thing is, this pump is probably 200% adequate for this job. Checking real voltage at the connector would be a good thing (while driving open loop 80mph on the freeway)
Paul has probably, maybe, watched this pump run out an open tank?
I have on accident. Ten 20 year old frat kids couldn't drink beer that fast.
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I don't have any of these issues on an 06 Lx 211k miles but eventually I'll climb a hill on a hot day. Is everyone just replacing these as part of pm now?
Interesting idea. IDK how to do that, do you? I'd only do short term as a test. Since driving like that too long, would likely overheat pump further.
"Manifold Temp" Are you meaning cylinder hard temps?
One other thing may be to pinch off return line. This increase fuel pressure in rails. If RPMs go up, it's a clue of low fuel pressure. Which is likely fuel pump and or fuel pressure regulator issue(s).
But usually with these 06-07 fuel pumps. That by just engine shutting down (stalling) and waiting a few minutes. They fire back up. So we tend to just drive without further ado!
I've one now we're trying to get ECT (engine coolant temp) down. One thing we're going to try is a new fuel pump. It had a crank no start, after a heat soak (boiling fuel). It's possible it's running lean at times due to heat soak and high outside air temp (OAT). Thinking is, heat increasing resistance in wiring and pump motor. The shutting down, may be clue of a bad fuel pump during heat soak. Slowing flow and pressure of fuel delivery to rails/injectors. Causing a lean running condition (hot cylinder head temps). Also fuel heating, may also reduce fuel delivery to cylinders, as molecules expand. Also adding to lean condition.
I did run pump by cranking engine with fuel line off filter. But it was not a heat soaked condition. I didn't measure volume either and didn't have issue with that fuel pump. It was on the Unicron. I now know, why it had gunk buildup at fuel hatch door. Engine CAT were overheating and thus so was fuel. I found the radiator fins badly clogged and suspect coolant was low for a long time (20K miles in one year). Engine got so hot, hoses disclosed and plastic melted, even the block was disclosed. I now know the gunk under the fuel hatch door, was sign of fuel boiling. Once I had it all back together. I test drove, it had no fuel pump (factory pump) issues or and any other.
But today I've a better understanding of the fuel pump issue in 06-07. As such I'm inclined to recommended replacement of fuel pump proactively.
What I see as they heat up, from running in it's high speed (engine pulling vehicle up a hill does this) typically on a hot day. They fail and engine shuts down, as pump relay drops power to pump for lower RPM low pump speed. It's not the relay but the pump itself that fails.
Wire starting at battery post and grounds, I do feel have effect. After all, corrosion and age increase resistance, reducing AMPs to fuel pump. So age certainly is a factor.
But my first experience with these 06-07 fuel pump issue, was in Snowy when brand new. PO (one owner) had complained from mile ~1. Toyota Dealership tested and tested, again and again over next 95K miles. Even had pressure gauge and tech stream hooked up and w/service manager, shop froman and mechanic (master) in the vehicle. Drove to into mountains to recreate and could not find any issues. They keep testing fuel pump time and time again. Finally for some reason, they just tossed in a new fuel pump. History showed the next 100K mile after new pump installed, and AFASIK, still works today without issue.
I'm convinced the factory pump in the 06-07 which is a smaller Denso than past (98-05 Denso and Aisin fuel pumps) years, has a defect. They get hot and resistance builds, pump slows, and then engine runs lean. Often stalling as pump switch back to low speed VIA relay reducing volts/AMP. Put in a new fuel pump and cleaning up battery post/cables/wire block and all works fine. Just pump resolves issue. But one's asking for issue, if battery area and grounds not serviced also.
To test pressure of these fuel pumps, is usually not going to be revealing. The best test is in real word on a hot summer day.
It's not a bad idea. But you can wait until first time you've a shut down.
Few tip when replacing fuel pump:
Relieve fuel pressure, by disconnecting wire block under DS passaged door and frame rail, crank engine, disconnect battery.
Hose off top of gas tank, once body access hatch under seat removed.
Replace tank seal at top of pump assembly.
See the schematic below. The fuel pump relay (FUEL PMP RELAY) does not actually switch the fuel pump. The Circuit Opening Relay has that task. The PMP Relay switches the fuel pump resistor in and out of the circuit. As drawn it bypasses the resistor. When activated by the ECU it engages the pump resistor. So by removing the relay and jumping it with a wire you can bypass it without too much trouble.
There is also some more information in the FSM DTC P0230. It shows the wiring diagram on the 3rd page. Pin 3-4 of the relay would need to be jumped to bypass the resistor. Pin-out of the relay is on page 4, section 2.
Furthermore there is reference in the FSM to use the Toyota Handheld Tester to select the Fuel Pump Speed with an active test. I assume that Techstream can do the same thing. That way it can be tested without any effort.
Sorry should have been clearer. I meant fuel rail temp. In my daily business fuel rails are called fuel manifolds (for things that fly).
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FWIW after changing out my 2006 pump to new one I no longer have this problem in at least in the last few hot months and with towing.
I would bet good money that pump is causing code P0430 for my case as I concluded in my post Annoying P0430 need to solve it. #89
so what would be good replacement for Fuel pump?
Did you go yeith oem or the Denso pump? If you go Denso do you also have to purchase the fuel filter "sock"? Not thr fuel filter in engine bay.
I went OEM. New sock and all. I so replaced the fuel filter.
My Cruiser doesn't stall, but seems to build excessive tank pressure. Been following this thread and was about to make a heat shield for the fuel line near the CAT. But I recently I towed my trailer using ethanol-free fuel going both directions and not only did the pressure issue stop my mileage doubled! Aster thinking about it I didn't have this problem before they only used ethanol in the winter.
I purchased a new FPR just to try it.
I purchased a new FPR just to try it.
On my OBDLink MX+, with the vehicle specific add-ons, I see vapor pressure (pump, and calculated), does anyone know what they're measuring, and where from? For reference, after being parked in my garage for a few days, it measured 14.1psi, highest it got was 14.3 I think driving around, but dropped down to 12.6 going up the grade on I-15 between Baker and Las Vegas, OAT of 113-115F, steady 70MPH in 4th gear (would not maintain speed in 5th or 5th unlocked).
I'm sort of surprised that nobody has tried an inline transmission fluid cooler on the return fuel line. I haven't looked for a place to mount it (that could be a challenge) but the theory is sound and the investment small.
***Update***
The dealer replaced the fuel pump and pump relay and I have since driven from Los Angeles to Tuscon AZ in 100+ degree heat for hours on end and Los Angeles to Mammoth in 100+ heat. In total about 3000 miles of hot highway miles with a RTT and pushing 80 MPH in the past 30 days with no stalling issue. I'm hoping the issue is resolved.
The dealer replaced the fuel pump and pump relay and I have since driven from Los Angeles to Tuscon AZ in 100+ degree heat for hours on end and Los Angeles to Mammoth in 100+ heat. In total about 3000 miles of hot highway miles with a RTT and pushing 80 MPH in the past 30 days with no stalling issue. I'm hoping the issue is resolved.
Eyedaho
SILVER Star
Pinching off your return fuel line sounds like a great way to leak fuel out of your injector seals and burn down your vehicle and garage.
