EFI relay - stalling at red light, won't start

[take123]

Hi 100-series wizards,

I have just been experiencing (2006 VVTI v8 4.7L), what I believe, is the dreaded EFI relay fuse issue. I have read this quite thoroughly on the ih8mud search and watched youtube videos about replacing the fuse box, even saw a video of one person opening the fuse box and squeezing the metal contacts so they can have better pinch. But before I start doing anything I wanted to get your people's take if my symptoms are related.

My vehicle has stalled once in 2024, twice in 2025, and now in 2026 this is first time. In 2024 and in 2025 the time it happened, it was in very hot weather, like close to 100F ambient. In 2026 now, we had the issue at 104F. I have taken cross country trips from Texas to California, and Texas to Alabama in between and no issue, this was during winter and spring.

When the problem happens, the car is stopped and idling, and the car starts shaking (like it's mis-firing) and pressing the Gas pedal has no reaction. 2024 was during stop and go traffic at a highway traffic jam in Houston. 2025 was at a stop sign and then at a red light in central Oklahoma. And 2026 was at a red light in North Texas. All in high summer temps.

When the car acts up at a stop, the engine shakes and sputters and dies and the warning lights turn on. I try to restart the engine, by turning the key from off to ignite, the starter motor makes sounds, but the engine isn't firing up. I can do this like 5-7 times, nothing. I wasn't paying attention if the orange CEL light comes on or not when I turn the key, I heard if CEL is off it is the EFI relay fusebox issue... so next time I'll pay attention to that. I'm just not sure if it's EFI related, why is it always when the car is stopped not when it's cruising at 70mph?

Usually if I let the car sit off for a while, say 10 minutes to 30 minutes, let it cool down, it will start up again no problem and pressing the gas the engine roars. If it's a weak connection fusebox, I'm wondering why does it ONLY happen when I'm stopped and coincidently when it's very hot outside. Maybe the plastic expands and something makes poor connection in the fuse box, and when it's idling it's shaking harder or the engine is rested in a position that makes the fuse box connection worse?

I was thinking maybe it's some other potential problems?
- MAF sensor needs replacing.
- Vacuum line, maybe there is a leak somewhere.
- Throttle position sensor, maybe this is gone bad and acts up in hot weather. Why when I press the gas pedal, nothing rev's in the engine.
- Bad fuel pump?
- Using Regular 87 fuel cause issue? All the times it has issue was (coincidently) when I was running Regular. I was running Premium after the issues started and never had the issue when running Premium. I only fill at Top Tier gas stations. In 2026 I started running Regular after the Iran war to save money on gas, but I highly doubt a Land Cruiser cares if it's 87 or 91/93 premium the engine is not a high compression engine...

Thanks,
Take123

 

[take123]

I did some more reading, and it looks like for the newer VVTI (2006-2007 LC100 / LX470) models, there is a common symptom of hot stalling problems. It looks to be a weakness in these years.

It looks like when the car is moving quickly in a hot environment, the air flow keeps the fuel lines cool and the fuel pump is injecting fuel at a higher rate. But when the car comes to a stop and RPM falls, the car will stall. A combination of lack of air flow and the hot engine and exhaust heating up the fuel lines, causes vaporization of the fuel, and also the fuel pump is pushing less fuel so there is less pressure pushing the fuel into the engine.

This causes issue when the gas vaporizes in high heat environments and when the car is still, there isn't enough fuel going into the engine, so the engine stalls. And then restarting the engine isn't possible, as you get the crank but no start problem. Waiting until the car cools and the fuel vapor returns back to a liquid state at lower temperature, will usually fix the problem.

Ways to address the above include:
- Replace the fuel pump with OEM / Denso. Need ensure it's 2006-2007 as the prior years use a different model fuel pump than the VVTI.
- Heat shield with reflective and insulating material, to cover and protect the fuel lines, block off the heat coming from exhaust pipes and engine block.
- Replace the fuel filter (proactive maintenance).


My car now is at 210K mi and never replace the fuel pump, so maybe this is the first step for me.... Not so sure it's the EFI / Fusebox at this stage, my fuse box is a 2006 ver so it's diff than the older 100-series that a lot of people cite fuse box pins getting worn down, not sure if it's more robust though. But at this point I think the Fuel / Vaporization issues may be the culprit.

The other thing I'm thinking is maybe camshaft or crankshaft sensor is wonky at high temp, and need replacing, high temp can cause electrical sensors to compromise. Or check if the wire harness is getting torn up from poor installation as the timing belt was changed at 170K.

Some past threads on the 06/07 hot temp fuel pump/vaporization issues:

Thread 'Stalling not just in High, Hot, & Heavy'

Jul 8, 2018

2006 LC100.

Twice in the last month the 100 has stalled and won't restart. Yesterday during highway driving and though it is warm out in CO in July, certainly not desert temperatures. Had a more classic feel of vapor lock (I know this is not necessarily a situation here). Vented the gas cap, waited, and would not start for 45+ minutes aside the highway (5 young kids in the car). Would turn over, stutter and then stall again. As is common a strong distinct vapor smell (though my 80 would stink constantly and yet never stall).

Previously in very tepid 70F degree day, came to a stall...

• Pskhaat
• Replies: 91
• Forum: 100-Series Cruisers

• 

Thread 'Dies When Hot'

Jun 27, 2024

Hey all,
I have a super annoying and very intermittent issue with our 2006 LX470- 130,000 miles.
This has only happened four times in the past year. Each time was a couple hundred miles from home, after driving for several hours, during very hot conditions and while pulling our small camper. The truck will either sputter and die when we are driving at slower speeds (fine at highway speeds) or won't start after turning it off. It will restart and run fine after letting it sit for a few minutes.

• No codes
• Turns over just fine. Sounds like it's not getting fuel.
• Currently running...

• Dan Porter
• Replies: 47
• Forum: 100-Series Cruisers

Post in thread 'Very strange: hot weather and sudden rough running, no power, major shuddering'

Jun 16, 2024

Good thought. It could very well be original. Is there any way to test this or should I just have it replaced?

Not sure if there is a way to test. Probably just need to replace it. There was an older thread about this issue and great details on how to replace it DIY (the fuel pump is under the rear seat).


This thread was on how to replace it:

Thank You Toyota! ...Fuel Pump Replacement.

Fuel pump started 'whining' last week, so its time to pluck the original out and replace it. Unlike the Starter on my LX470....the fuel pump is actually easy to replace. You do NOT have to drop the fuel tank in order to do this repair. Most folks know there is an 'access panel' under the...

forum.ih8mud.com

• newbielx470

I

Thread 'Dreaded LX470 cutting out no codes!'

Aug 5, 2022

Hey all,
Last couple of weeks after no mods or anything my 2005 LX470 has been cutting out while driving. I’ve been trying to establish a pattern of when it happens but the closest I can get to is when I make a turn and/or on a decline, slight one usually. Today it happened in an incline! No signs prior, all I get is cut out, lights in dash reset and sometimes I can save it and drive away and sometimes I have to roll off to the side with no PS and restart it. Anyway I have read a lot from other posts and have initiated a troubleshooting plan so wanted to give back to the community and let...

• ivn351
• Replies: 12
• Forum: 100-Series Cruisers

Thread '2006 LX Engine Dies After Climbing A Hill and Then Idling'

Mar 12, 2020

After climbing a large hill the engine tends to die if I get off the gas. This has happened a couple times. Once while coasting down the hill and another when I came to stop light after the hill. The gas tank has been full and half full. The weather has been warm and cold. The local dealer (I work there too), first cleaned out the throttle body. The problem remains , so the techs best guess is fuel pump. Even at my employee cost, a fuel pump is still a grip. I just thought someone might have some insight before I spend the cash. Thank you for your help.

• Filthy Lexus
• Replies: 15
• Forum: 100-Series Cruisers

Thread 'Sudden Loss of Power AGAIN - On road with family [St. Louis,MO]'

Jul 21, 2019

I would appreciate any help and will be cross posting in the clubhouse forum for MO.

I am currently traveling from MD to CO. I had an issue ~8months back [THREAD HERE] it was diagnosed as the MAF which was replaced with an OEM part. I have had no issues up until yesterday. I was on my 2nd day of trip and after driving ~4 hours I pulled off the highway to get gas. I stopped at light and when I went to accelerate I had sudden loss of power, truck would not move and stalled when I fully pressed on accelerator. I did the same routine as previous, disconnected battery & cleaned MAF...

• frogers935
• Replies: 58
• Forum: 100-Series Cruisers

S

Thread 'HELP! LX470 cuts off while driving'

Apr 28, 2022

I hope there is someone who can assist me with my issue. 2006 LX470, 180K . I have owned it for close to 2 years- It was involved in a minor front end collision before I bought it. No airbags. The LX retains all original factory sheet metal. What was replaced was the Bumper and 1 headlight assembly. Installed a TJM bumper and removed the running boards. I had ALL the fluids changed, belts hoses, etc....water pump.....etc. Ran great until about 6 months ago, it died while driving several times. No Codes. We replaced the fuel pump with a factory part and it ran great for 5 months. Then it...

• Samuel5090
• Replies: 48
• Forum: 100-Series Cruisers

K

Thread 'fuel issues 2006 LX470'

Sep 10, 2012

I have a 2006 LX470 that I purchased a little over 3 months ago. When hot out and driving quite a bit it would be hard starting, just like a vapor lock, until it cooled down then starts fine.

Also I get a fuel vapor/alcohol odor when it is hot out as well, and this odor comes from underneath the vehicle near the charcoal canister or filler tube.

Problem got to the point where the car would stall in traffic. I replaced the fuel pump as fuel pressure when hot was 32psi, and 38 when cool. New pump measured at 40psi according to my mechanic. Still get the occasional hot start issue when...

• kklaus121
• Replies: 6
• Forum: 100-Series Cruisers

Thread 'Failing Fuel Pump Symptoms? Edit: Now With Data'

Jul 9, 2022

2007 LC, 194k miles. As far as I know the pump is original, filter was replaced about 65k miles ago. Currently on my way to Michigan.

Two days ago I drove from Boise to Ashton, ID. Drove perfectly fine the whole way until I missed my turn on a FS road and had to jab on the brakes fairly hard (not nearly hard enough to engage ABS though). I put in it reverse and notice the truck is really struggling to keep running and a few seconds later dies. I crank a few times but no start. I checked the fuel cap, no pressure escaping or fuel smell. I waited a few minutes and it fires up like nothing...

• GTV
• Replies: 53
• Forum: 100-Series Cruisers

Thread 'Troubleshooting engine stall'

Aug 10, 2018

I came in off the highway yesterday and at the first light my 06 LC stary d to run rough and I could get any rpm when I gave it gas. At first I thought it was the throttle position sensor. After I limped off the road it died and won't keep running after cranking over. After calling a tow truck she fired up and I was able to drive another 20 miled before having the same problem after coming down from speed into a traffic circle. After ten minutes it will fire up. This morning I'm putting a new gas cap as it won't click anymore so it may have a negative vacuum from not breathing. Also going...

• mountainman1477
• Replies: 28
• Forum: 100-Series Cruisers

M

Thread 'Bad Fuel Pump Symptoms - My experience'

Jul 23, 2019

Hey gang, its funny that prior to these hot temps there was not a lot to be found on here for the issue i was having leading up to what ultimately left me on the side of the road. I wanted to share my experience of the symptoms my 2007 Land Cruiser was showing and what I did to address it and what ultimately cost me a day of fishing for being on the side of the road.

About a month prior, I was experiencing a slight surging sensation at between 2100 RPM and 3000 RPM. Sometimes in lower gears but mostly noticed on the highway between 65 and 75 mph while gradually accelerating. The...

• mallard75
• fuel pump p0171
• Replies: 10
• Forum: 100-Series Cruisers

• 

 

[take123]

For those wondering, I decided to replace the fuel pump first.

These are the parts I bought. There was a DENSO part that is similar, reference : 2006-2007 fuel pump denso #950-0210 instead of 23220-50160 - https://forum.ih8mud.com/threads/2006-2007-fuel-pump-denso-950-0210-instead-of-23220-50160.1100698/

However, I decided to use OEM Toyota as I didn't want to deal with using a part from a Sequoia and needed a 100% fix as it gets hot as balls here in Texas and don't want any more issues of car stalling and having the crank-no-start symptom when it's really hot.

	Part No.: 23220-50160PUMP ASSY, FUEL W/FI	1pc
	Part No.: 90467-12067CLIP	2pc
	Part No.: 23239-11010HOSE	1pc

My diagnosis logic is the following:
- Car stalls at red light/stop sign after driving for hours in 100F+ outdoor temps. This only occurs when it's hot as hell and car is pushed hard.
- Coming to a stop after running the car for 85mph+ for hours, the fuel lines get hot. The cats on driver side are next to fuel line, those get hot, the gas tank gets hot, the fuel pump gets hot, everything is hot. In future, I'm thinking to shield those fuel lines off and install a metal plate next to the cat to reduce the fuel heat soak. My thinking is the stalling and no-start after coming to a stop after hot operation is caused by a combination of fuel vaporlock and the fuel pump dying out intermittently. When the fuel pump dies, theres no pressure on the fuel lines, not 100% sure there is vapor lock from the heat as it's unlikely for a fuel injected system like the LC, but anyways a dead fuel pump means no fuel being pushed into the engine, so it runs too lean and then dies. This explains why pressing the gas does nothing to the engine. And explains why when I let the car cool off, it starts up again no problem. The last time this happen last week, on my return trip (also hot as heck outside) I drove the car at 65mph not 85mph and it was okie dokie at stops.
- My logic here, is when the fuel is hot, the fuel pump has to work harder, the motor in the pump is immersed in the fuel tank and uses the fuel to cool off. As it gest hot, resistance of the copper goes up in the motor, means less juice to power the motor. My battery terminals are also very corroded to they likely aren't getting the full juice, so this means the voltage sees less voltage than it should, will sand down the battery contacts and clean them up too. When fuel pump is hot, the bearings and mechanical tolerances also get worse as the metal expands, this causes more friction and mechanical resistance, until the motor locks up because there's not enough juice to move it. Higher temps can also cause motor to have issues as the insulation around the copper wires inside the motor can start to wear and fall off, causing shorts between the copper windings, but not so sure this happened here as the fuel pump largely works still.


I also thought if going premium will help, but doing research indicates that premium v regular is basically no effect on vaporization point of the fuel. The octane level, has nothing to do with how the gas evaporates due to heat/altitude. Ethanol content matters more than octane rating for the vapor lock. And basically all the gas stations I use has 10% ethanol mix, ethanol boils at lower temps than pure gas. So those that can find pure gas, the vaporization issue from heat or high altitude will be improved, but I cannot rely on 100% gasoline. It should also be noted in summer time, gas vaporization point is higher than in winter blends. So if it's winter time and you get a sudden spike in high temps, it can cause issues for vaporization point. On my return trip from the issue symptom I saw last week, I ran Regular, and drove at 65mph instead of 85mph, easy on the gas, no issues. So it's not a Premium thing.

A car like the land cruiser, should NOT be experiencing vapor lock issues like this. This car is designed to run in the middle east and Australia without issues, so I doubt there is a design tolerance issue, but more a wear on a moving part. Notably the fuel pump motor. My car was made in late 2005, so this car is already 20 years old and I think a fuel pump at 20 yrs and 210,000 miles has done enough in its life, so let's try to replace this first before challenging the high heat capabilities of the LC100.


Will let the board know if anything improves, but it's hard to reproduce as it's only showing when driving at 100F+ temps at high RPM's for hours.

 

[iankeever15]

TAKE123! I have a new to me, 2006 LX470 that is experiencing these EXACT same issues. When outside air temp reads at least 103 degrees. At an idle, I get the engine shake, rough idle, to stall. Crank, kinda start, rough idle, shake, stall. Wait five minutes, cranks and starts just fine. I am in northern UT, daily driving at 4,500'-5,000'. Like I said, this has only happened on extremely hot days. Runs just fine otherwise. I am at a loss at where to start after reading all of the threads. I have cleaned my throttle body and MAF with no success. I will be really curious if the fuel pump solves your issues. Please let us know! I do realize it can be hard to replicate.

 

[take123]

Around 3 weeks ago I took a trip from Dallas to Austin. It was like 104F outside on the 35.
Driving 75mph the car eventually stalled when I got off an exit to go get food. Let the car sit on the side of the road for 5 min with hood open, she started back up fine, then drove slowly to restaurant.

Letting the car cool down while I ate, the car was able to start up fine afterwards, and drove the rest of the way without issues, I just drove slower like 55mph keeping RPM's low.

This week took the car to mechanic with the new OEM fuel pump. We're going to replace that first and see how it goes. Will have another trip in Oklahoma in a few weeks so it should still be hot as hel, so can test the new fuel pump in 100F+ weather and I'll try driving it hard.

 

[hoser]

A car like the land cruiser, should NOT be experiencing vapor lock issues like this. This car is designed to run in the middle east and Australia without issues, so I doubt there is a design tolerance issue, but more a wear on a moving part.

Middle East and Australian 06-07 were equipped with the Non-VVTI, 2UZ-FE.

 

[Hornd]

Why not hook up a Fuel Pressure Gauge and see what the Actual Pressures is during Failure?
My Corolla was having issues Starting after being Shut off Hot.
It would sometimes crank 20X before starting.
I put in a new Fuel Pump and issue never Repeated.
Original Pump had 330K Miles on it.
Aiming the Parts Cannon at it gets Expensive & Frustrating.

 

[2001LC]

Hot no start:

The 2006 has a TSB: "Hot soak". In which, some have a defective cam sensor. That may or may not set off a DTC (code).


Rough idle stall:
A common issue I see. Is flooded charcoal canister. We almost always smell fuel, near LH rear 1/4. It very often smell like very old gas

One more issue is engine coolant temp (ECT). So often I'll see ECT running to hot. Leading cause is radiator fins clogged.

Thread 'Radiator fins need cleaning! Alert Alert Alert'

Jul 22, 2019

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added radiator cap and thermostat to job, as best practice.

Got me to thinking about the radiators I've been replacing. All have debris built up on lower third.
This one hand some extra grasses along with general clogging on lower third.

Over the years/miles debit builds up in condenser and...

• 2001LC
• Replies: 35
• Forum: 100-Series Cruisers

• 

 

[DMCTX]

I had the same thing happen to me in DFW area last week in my 2006 LX470 with 306k miles. Hot day, traveling at 75 mph, traffic stopped and it started shaking and felt like a misfire. Gas pedal did nothing and I had to be pushed off the highway. Once the car cooled off, it started and ran fine. I'll be interested to see if the fuel pump is the culprit.

 

[NeedaLX]

The same happened to me last year in my 2006

I had the fuel pump replaced but have not truly replicated the conditions it happened in since then

 

[Deflagrate]

This happened to me on my way to and again on the way back from SAS in my '06. Both instances were stops after at least half a day of driving, temps in CO were in the upper 90s IIRC (and this is also after driving over monument pass on the way there), temps in Texas were mid 100s. Fuel pump was replaced earlier this year when I had to replace the fuel level sending unit. Second time I was also trying to get gas and I could not fill up. Letting the car sit for a few minutes (gas cap was off), I was able to fill up, and then it started up no problem. Guessing it is the charcoal canister, since my pump is still fairly new. May just try some heat shielding on the fuel lines first. I haven't smelled anything, but my nose also isn't the best.