2UZ-FE High Long Term Fuel Trims
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I've long been wondering about fuel trims, especially LTFT1 and LTFT2.
Using Torque Pro my LX470 has them close to 0.0 at idle and all over the place while driving.
At steady highway speeds they usually are around something like 5.0 or 7.0
Using Torque Pro my LX470 has them close to 0.0 at idle and all over the place while driving.
At steady highway speeds they usually are around something like 5.0 or 7.0
I really no idea what your mechanics print out is showing. Not something I use.
Compression is stated by cylinder 1, 2, 3, 4, 5, 6, 7 & 8. in PSI (or other pressure unit). Stated as a percentage may refer to leak down IDK or effecnice or RPM drop at cylinder IDK. There is a test in tech stream, which we can get indication of cylinders. But A, B, C etc, IDK which cylinder so IDK know which bank. The low 83%, if indication of 14PSI differential below high cylinders of 100%, is a failure. It may also be below 154PSI. I may also be clue of a bad fuel injector or coil or spark plug. IDK, as not how I run tests.
The USA 4.7L 2UZ-fe in 2006-07 (2007, last year of 100 series in USA market). Has the 4.7L VVti engine. It also has the S.A.I. system, which is to reduce pollution. If you have the S.A.I. system. You must do my filter mod. We need to know: Has filter already failed. It's a clue!
S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert!
We've a $2.00 part in the S.A.I. (secondary air injection) system of the VVT engine, that is taking-out ~$7,000.00 $15,000 $25,000 (inflation) in parts. WOW! I've a very easy and cheap WORK AROUND. You are going to love this ;) This thread is dedicated to the 4.7L 2UZ-fe VVT engine, in the...
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I use both BlueDriver & OBDmxII for iphone. Bluedrive is easier to connect, and gives best moment to moment accuracy of Fuel trims (FT) IMHO. But limited on data points that can be monitored (no CAT, AT temp or AHC in my 10 yr old Bluedriver). OBDmxII, uses most any software. So we can use various downloads apps, and see much more data. But seem less acculturate. Both display on iphone and record log in background of entire trip. Logs are saved and can be downloaded to spreadsheet.
LTFT & STFT both banks, along with ECT, IAT, RPM and MPH. I'm most interested in FT while at ~ 65MPH on HWY with RPM and MPH steady (No hills or change in throttle). Which seeing, MPH & RPM in log. Clues me to those points, in the logs. That I'm cruising steady. They, both log in the background, the entire trip moment to moment until I shut down. If LTFT above 5% we have any issue needs correcting. LTFT (long term fuel trims) are what ECM is doing to correct STFT (short term). So seeing say 10% LTFT, means engine running lean and ECM increasing gas via fuel injectors, to richen air fuel mixture. If one BK only, it's a bank issue. If both banks, the issue which can be same in both or something between air filter box and throttle body. I.e MAF. Some are more than one issue.
Here's a 06LC w233k miles, I test drove in last week. Owner complains, some hesitation on HWY pull up passes around 2,500 to 3K RPM. He's had, many very good shops try to correct. I just took test drive and watch FT, something no mention of by anyone else. Everything has been done, on this one. Except fuel pump and filter has never been R&R. Nor has: S.A.I filter been inspected or compression tested or fuel pressure test done. I'll be inspecting S.A.I filter, with borescope, may do compression test and fuel pressure test. I will be R&R fuel pump and filter. It may be a case of very bad fuel flow, due to bad gas. I'll likely also replace the MAF sensor, later. After I see if fuel pump & filter has effect. I see many improved FT & MPG, by R&R old MAF sensors.
Screenshot of iphone, running bluedriver. MPH hidden from view, but was steady~65MPH as was RPM ~2,100.
Finding reseason FT not as should be, is both and science and art.
One I've found when both LTFT over 7%: Bad gas clogged fuel filter and fuel pump sock.
This one, 4.7L VVti, where everything was it should be. But best we saw, was: LTFT1 & LTFT2 7%. In the end we replaced fuel pump and filter, LTFT came in a 2%. Gas tank had rust from bad gas clogging and reduce fuel flow. It one reason I like watch FT on HWY at around 65MPH. .
Vacuum leak before intake manifold gasket (of side side), effect both banks. Bad fuel injector or compress can be both banks, but more often just one bank. Exhaust leak typically don't hurt unless very bad, but can and be easily detected. Spark plugs loose or bad coil, usually that bank.
One I just help with. Had high LTFT. Then a P0303 (misfire #3 cylinder).
Coil good,
Spark plug good,
Spark good
Compression good.
No change in RPM #3 fuel inject power cut. We had four FI injector rebuild by FIS. Install the four in BK1 fuel rail. Problem solved, no more P0303. But BK2 LTFT a bit higher now then BK1. Owner plans on BK2 FI rebuild later.
When to Clean or Replace fuel injectors
Please post your experiences and thoughts on the subject. I’ve been considering cleaning or even replacing all 8 fuel injectors, is this wasting time and money. I understand keeping fuel injector clean by adding a can of additive to the gas tank, now & then, is a good practice. This keeps them...
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I've also seen weak coil or junk coils cause issues with fuel trims.
When to replace Ignition coils.
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Also, spark plug walking or junky china bootlegs.
Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!
TICK TICK TICK POP POP POP is a ticking time bomb, often mistaken as exhaust manifold crack or gasket leak leak. ALERT, ALERT, ALERT: Spark plugs are working themselves loose. "Walking Out" Then blowing out of head, taking their female threads of head with them! Very damaging! You think TICK...
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Thanks for your through responses @2001LC
As far as I can tell my 2007 200 series 2uz vvti should have SAI - 2UZ-FE Toyota engine – Australian Car.Reviews - https://www.australiancar.reviews/2uz-fe-toyota-engine/?
I've also attached a test I found for cylinders with numbers and PSI. What would this indicate to where I focus on? My mechanic checked spark plugs and coils.
At the time, spark plugs were loose but they were fixed. LTFT issues remained also I saw some improvement in economy, its still awful though. 23-26 L /100km (weight around 3.6T)
As far as I can tell my 2007 200 series 2uz vvti should have SAI - 2UZ-FE Toyota engine – Australian Car.Reviews - https://www.australiancar.reviews/2uz-fe-toyota-engine/?
I've also attached a test I found for cylinders with numbers and PSI. What would this indicate to where I focus on? My mechanic checked spark plugs and coils.
At the time, spark plugs were loose but they were fixed. LTFT issues remained also I saw some improvement in economy, its still awful though. 23-26 L /100km (weight around 3.6T)
- Thread starter
- #46
@2001LC , for the engine with the clogged filter, did you notice any other symptoms, like lower-than-spec fuel pressure? I'm still running in the +5-10% range but attribute that to my engine mods which include a tune and our crappy 10% ethanol fuel here. I have about 41-42 psi on the fuel rail.
The engine still runs good with tons of power so I haven't worried about fuel trims in some time. Just interesting to see this thread get ressurected!
FYI, I did have to replace my MAF connector again last year. I'd be driving and then STFTs would start going bonkers. I'd watch the MAF reading at idle and see it was ready super-low. Fiddling with it helped the problem - so I re-did the connector with extra-care on the splicing. No issues since.
Another guy on the GX470 forum had the same issue. Seems like the MAF connectors on the 2UZ are kind of fragile.
The engine still runs good with tons of power so I haven't worried about fuel trims in some time. Just interesting to see this thread get ressurected!
FYI, I did have to replace my MAF connector again last year. I'd be driving and then STFTs would start going bonkers. I'd watch the MAF reading at idle and see it was ready super-low. Fiddling with it helped the problem - so I re-did the connector with extra-care on the splicing. No issues since.
Another guy on the GX470 forum had the same issue. Seems like the MAF connectors on the 2UZ are kind of fragile.
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So a 4.7l VVTi with the air box and heater tees of the 200 series 3UZ. And RHD. Cool.
Your compression numbers indicate a fail test based on Toyota spec. You've one or two cylinders below minimum and greater than 14PSI differential.
But a few things affect this test. First, test must be by the book:
Engine at Op temp.
Throttle body wide open.
250 RPM minimum.
Fuel cut off.
Sea level. Here in mile high city, we get little lower read, than those at sea level.
Low compression, according to aircraft engine manufactures'. Does not affect HP.
But IMHO, it can effect FT trims, also CAT can get loaded up and damaged.
If it came to me. First I'd inspect the SAI filter.
I'll repost this, I suggest you and your shop reads this.
S.A.I. Filter Modification, in VVT engines. To prevent its failure! Alert Alert!
We've a $2.00 part in the S.A.I. (secondary air injection) system of the VVT engine, that is taking-out ~$7,000.00 $15,000 $25,000 (inflation) in parts. WOW! I've a very easy and cheap WORK AROUND. You are going to love this ;) This thread is dedicated to the 4.7L 2UZ-fe VVT engine, in the...
forum.ih8mud.com
Than I move to other testing, if needed. Much of which I talk about above.. Leave no stone unturned!
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SAI has no effect on fuel pressure.
Damage, due to lack of filter air form SAI. Can cause compression issues. Which compression, can affect fuel trim reads.
MAF are super sensitive instruments. I R&R (remove & replace) more as are fleet ages, as a PM. I only use OEM MAF sensors, when replacing. I always disc onnet battery first.
- Thread starter
- #51
My apologies, I meant the clogged fuel filter, rather than the SAIS filter.
I may run a compression check on my rig at some time just to check the heath. Maybe next time it gets a set of plugs.
@2001LC I'll look seriously into the SAI. I am pretty concerned about this machine though. If you were in my shoes with little experience or knowledge, and difficulty finding specialists around where I live now, would you be selling this car instead and moving on? or stick it out? its got around 20k AUD of extras on it and only 140,000kms. The sunk cost does have me feeling pretty tethered. I hope it doesn't turn into a crazy expensive exercise. Will look into the SAI like you say first.
No.
First, I've just given you possible for LTFT high. Food for thought and or to show your mechanic.
Your compression test, may not have been done by the book. Even if, PSI correct. I've seen worst.
It could be very minor issues, affecting fuel trims.
The SAI, is easily correctable IMHO. Any mechanic can do typical SAI repair. Any, can also read my filter mod and do it easily
I see these SAI filter, fail around 150K miles or more less. Once they fail, takes time (many cold starts) to do damage to cylinders. Unless you driven daily on dusty dirt roads most every cold start. Which increase dust, speed up the damaging dust effects, of blowing through system.
Worst case, engine can be rebuilt or replaced. If solid bones, it's worth it. If a rust bucket, dump (sell) it.
First, I've just given you possible for LTFT high. Food for thought and or to show your mechanic.
Your compression test, may not have been done by the book. Even if, PSI correct. I've seen worst.
It could be very minor issues, affecting fuel trims.
The SAI, is easily correctable IMHO. Any mechanic can do typical SAI repair. Any, can also read my filter mod and do it easily
I see these SAI filter, fail around 150K miles or more less. Once they fail, takes time (many cold starts) to do damage to cylinders. Unless you driven daily on dusty dirt roads most every cold start. Which increase dust, speed up the damaging dust effects, of blowing through system.
Worst case, engine can be rebuilt or replaced. If solid bones, it's worth it. If a rust bucket, dump (sell) it.
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I’ve been digging in deep into your posts and the SAIS in general as much as I can without removing the air intake.
I think if the SAIP is currently connected to the filter and snorkel (I dont actually know that though) I dont want to mess with that topology because I need a snorkel for water crossings. I’m willing to stick with the stock setup and replace it as often as might be necessary if I know the symptoms to monitor for to pre-empt it.
I ordered a bluedriver. I’ve a got a few more questions I've been wondering about as I've been learning:
This is a vid of LTFT at highway speeds:
And these are cat temps at highway speeds (at the start)
I think if the SAIP is currently connected to the filter and snorkel (I dont actually know that though) I dont want to mess with that topology because I need a snorkel for water crossings. I’m willing to stick with the stock setup and replace it as often as might be necessary if I know the symptoms to monitor for to pre-empt it.
I ordered a bluedriver. I’ve a got a few more questions I've been wondering about as I've been learning:
- Is the SAIS supposed to normally take its air from the airbox and snorkel? It’s not sclear what its input is connected to.
- Will that air filter mod affect my ability to do water crossings? Already running a snorkel and it has done a few.
- Can the SAIS filter and 3 valves be replaced or does the whole unit need to be done?
- I went looking over any records of DTC’s and found P0102 (MAF circuit Low) and P0113 (Intake Air temp Circuit High Input) had occured where diagnostic said these codes were current and in the history. if they have happenned multiple times, could that be caused by a bad SAIS valve? Might be unrelated though or just a bad connection.
- Would a bad valve explain why I’d see different o2 readings of each bank and cause a lean condition?
This is a vid of LTFT at highway speeds:
And these are cat temps at highway speeds (at the start)
First: The S.A.I. system. Would not directly affect your fuel trims. It runs only on cold start up, for ~ 90 seconds. It force air into exhaust ports of head, then into CATs. Just to heat catalytic converts (CAT). In U.S.A. model 100 & 200 series. The air intake of the S.A.I. systems. Are completely independent (separate) of the engine air intake (to throttle body, for combustion air intake). So, they are not connect in anyway to U.S.A. aftermarket snorkels.
Second: your engine does look like a 4.7L. But has differences. Such as: Oil dipstick on BK 2, air filter box and tube, heater Tees are all like a 200 series 5.7L U.S. model. Note the U.S.A. 200 series 5.7L, has S.A.I. Air Pumps. Located in the front of RH tire, hinden in the front fender well.
You may or may not have the S.A.I system. IDK!
We began seeing CATs, in U.S.A. engines, in the early 1970's. They reduce pollution. All U.S. engine driven on public roads, are required to have them. To meet EPA mandates (LAW).
S.A.I is a system to meet U.S. EPA pollution law standard mandated ~2005. They're in U.S.A. 100 series 2006-2007 4.7L 2UZ-fe VVTi, as required by Law.
We can look at from of engine and peak under the intake manifold and see the S.A.I. Air Pump (blower).
Look under intake manifold, with flashlight, where red arrow points, To see S.A.I. air pump.
Here, intake manifold is off the engine, exposing S.A.I Air Pump, main Air Switching Valve and starter
The first black round cap with tube pointing toward back of engine, is the Air Pump.
We can also look at back of engine, on top of rear water bypass and see BK1 & BK2 S.A.I. switches (valves). We can also see the tube coming off the BK1 & @ Sw's running to exhaust manifold. Yellow arrows pointing to.
Second: your engine does look like a 4.7L. But has differences. Such as: Oil dipstick on BK 2, air filter box and tube, heater Tees are all like a 200 series 5.7L U.S. model. Note the U.S.A. 200 series 5.7L, has S.A.I. Air Pumps. Located in the front of RH tire, hinden in the front fender well.
You may or may not have the S.A.I system. IDK!
We began seeing CATs, in U.S.A. engines, in the early 1970's. They reduce pollution. All U.S. engine driven on public roads, are required to have them. To meet EPA mandates (LAW).
S.A.I is a system to meet U.S. EPA pollution law standard mandated ~2005. They're in U.S.A. 100 series 2006-2007 4.7L 2UZ-fe VVTi, as required by Law.
We can look at from of engine and peak under the intake manifold and see the S.A.I. Air Pump (blower).
Look under intake manifold, with flashlight, where red arrow points, To see S.A.I. air pump.
Here, intake manifold is off the engine, exposing S.A.I Air Pump, main Air Switching Valve and starter
The first black round cap with tube pointing toward back of engine, is the Air Pump.
We can also look at back of engine, on top of rear water bypass and see BK1 & BK2 S.A.I. switches (valves). We can also see the tube coming off the BK1 & @ Sw's running to exhaust manifold. Yellow arrows pointing to.
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For now, just look to see if you have a S.A.i. system. Note it, as a side note and table it. We can dig deeper into it, some other time. As it will not directly affect the fuel trims. So table it!
You are for sure running lean with LTFT1 & 2 showing ~17%, while cruising steady on HWY.
ECM is correcting STFT (Short Term Fuel Trim), best it can. By increasing fuel from fuel injectors. Working to get correct STFT, to a baseline of 0% (14.7 parts air to 1 part fuel) The LTFT, is what ECM is doing to correct short term.
Why engine running lean fuel air mixture (lean of fuel mixture).
High LTFT above 5%, is cause for concern. At greater 20%, we get a CEL (check engine light). A lean condition is ether to much air in mix, or to little fuel in mix.
Most lean condition, are due to a vacuum leak(s). Number one, is a vacuum line/hose disconnected or damaged. This effects both BK1 & BK2 (FT1 & FT2)
I've seen, where intake manifold bolts not torqued down (loose). So air enters between intake manifold & heads intake ports, on both banks. This is what the intake manifold gaskets seals. I mention this. because in your picture. The wire harness block, connected to throttle body. Is missing the rubber boot, we see in U.S.A. 4.7L VVti. If yours is indeed missing. It indicates someone has worked on around throttle body & intake. So much of what I do, is correct what other hands have touched.!
Bad MAF sensor, can cause both rich & lean condition. But I see these, mostly result in a rich condition.
Fuel starvation, also result in a lean condition. This can be issue anywhere along fuel delivery system. But most common, is clogging fuel filter. It could be a bad fuel pressure regulator or fuel pump, resulting in drop of fuel pressure or flow also.
It can also be a compression issue. But most with bad compression result in a rich condition.
So look for vacuum leak. Rule it out first, as most common
Google/youtube search: How to find vacuum leaks.
It is connected, just a strange image.
I can see the SAIP here. My thinking was if it was connected to the same air intake and a valve was suck open exhaust could fed back through but if thats not possible then yes lets table it.
I have done a propane test around every part I could reach but saw no change in STFT. I added propane round the snorkel as a control and saw it should show something if I found a leak elsewhere. I'm not sure what I might try next to find vacuum leaks. I'll look into other ways to find vacuum leaks though.
I've also attached the results of my injector tests and compression tests. All injectors were balanced, so would that mean we could rule out fuel delivery?
Since we see differences in both o2 sensors (S1 & S2) on bank 2, can I rule out o2 sensors as being faulty?
I 'think' we can rule out MAF since a problem there should show up in both banks, correct me if I'm wrong. although on full throttle LTFT never gets below 4.7 for both banks and values are identical, so could be a seperate contributor. Need to monitor calculated load apparently (not sure what gauge that is) to see if it gets into the high 90% when flooring it.
One more person suggested they had FT issues and it was caused by the valves. Perhaps after vacuum leaks I might look into that next?
I can see the SAIP here. My thinking was if it was connected to the same air intake and a valve was suck open exhaust could fed back through but if thats not possible then yes lets table it.
I have done a propane test around every part I could reach but saw no change in STFT. I added propane round the snorkel as a control and saw it should show something if I found a leak elsewhere. I'm not sure what I might try next to find vacuum leaks. I'll look into other ways to find vacuum leaks though.
I've also attached the results of my injector tests and compression tests. All injectors were balanced, so would that mean we could rule out fuel delivery?
Since we see differences in both o2 sensors (S1 & S2) on bank 2, can I rule out o2 sensors as being faulty?
I 'think' we can rule out MAF since a problem there should show up in both banks, correct me if I'm wrong. although on full throttle LTFT never gets below 4.7 for both banks and values are identical, so could be a seperate contributor. Need to monitor calculated load apparently (not sure what gauge that is) to see if it gets into the high 90% when flooring it.
One more person suggested they had FT issues and it was caused by the valves. Perhaps after vacuum leaks I might look into that next?
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I have also noticed that when idling, the idle revs do change a bit.
between 690-830RPM which is quite a range. Is that normal? If not, then that would also point towards a vaccum leak. ignore the intake temp question in the video.
Also, what about valves? if they need resetting could they be affecting this?
between 690-830RPM which is quite a range. Is that normal? If not, then that would also point towards a vaccum leak. ignore the intake temp question in the video.
Also, what about valves? if they need resetting could they be affecting this?
I think with data you've collected: I'd pull fuel filter and inspecting filters backflush.
Fuel flow:
I see in a video, you have a read out of fuel flow. But, AFASK, we have know actual device reading flow (GPM) in 100 series. It's likely calculate based on other data ECM collects.
One thing I don't see, nor do I have equipment for. "Fuel flow". Go back to post #43. In that one which ran lean (LTFT high). I R&R the fuel pump & filter. Fuel trims, came in line for the first time afterwards. It was a fuel flow issue, due to bad gas. It passed all fuel system test, before R&R.
Fuel system test:
When I check fuel pressure and leak down, by the book. This mainly test Fuel Pressure Regulator working within spec, fuel pump creating PSI within spec and leak down pass or fail (all injectors at once).
Your compression test:
No big concerns on cylinder compression. Many engine with similar low compression and, but your differential a bit high.
I see compression above the minimum PSI of 142PSI. But all low, with #1 150PSI & #2 172PSI. Which is fail in differential of 14PSI spec. With a 22PSI differential. I do not see wet test.
I see cylinder leak down test done at ~30PSI. I do them at ~90PSI. I do not see notes on where down leak i.e. rings, valves, head gasket.
We also don't know how fast mechanic to, beginning test after shut down, nor RPM or if he had throttle body wide open. But let us assume, he did by the book.
The differentials in PSI. Tends to make idle a bit rough. BK2 runs leaner (LTFT2 higher by ~4%), BK1 slightly less correcting as shown by LTFT1 to richen mixture. Makes some sense, based on cylinder (compression) balance. This could account for idle not being steady. But until LTFT bought in line. I'd not make to much of idle RPM variance.
Your vacuum test, indicated no vacuum leak: So' id move on to fuel starvation testing.
BTW: Just as a point of interest. The VVTi 4.7l upstream, is actually a A/F sensor, not o2.
FWIW: I'll be running a fuel pressure test & cylinder compression test today. Mostly to collects data.
On a 23,500 miles 2007 LC VVTi. More to collect data, on lowest miles Land Cruiser know in USA. As reference points, but also part of base line restore. Since, super low miles, can and do have issues. Fuel system related issues, mostly.
I'm getting a little "D" vibration, which is talk about in this forum. Engine runs a bit rough at 2,000 RPM (stationary in park). On HWY, at over 4,500 RPM. It has a bit of an oscillating droning sound.
It's, fuels trims are good. But I feel could be a bit better, for engine barely broken in. It may have some spray pattern issues. I'll be sending them out to be tested by FIS. Then we'll know without any doubt.
Idling
Flat HWY steady RPM & speed
I'll also R&R fuel filter. Then blowing-out on bench. To see if clean or dirty backflush. The vehicle came from small rural city. Which we see more old gas station, with old metal tanks. If filter, shows signs of dirty fuel. I'll then go deeper and inspect fuel tank/pump.
On this 07LC. I did find one concerning issue. Muck in fuel filler door/cap area. Fuel cap letter unreadable. This points to fuel boiling, where fuel comes out the cap. Which was likely caused by, overfilling gas tanks (100 series 03-07 issues). Which both overfilling & boiling, floods the charcoal canister. The EVAP system can also, cause fuel trims issue.
Fuel flow:
I see in a video, you have a read out of fuel flow. But, AFASK, we have know actual device reading flow (GPM) in 100 series. It's likely calculate based on other data ECM collects.
One thing I don't see, nor do I have equipment for. "Fuel flow". Go back to post #43. In that one which ran lean (LTFT high). I R&R the fuel pump & filter. Fuel trims, came in line for the first time afterwards. It was a fuel flow issue, due to bad gas. It passed all fuel system test, before R&R.
Fuel system test:
When I check fuel pressure and leak down, by the book. This mainly test Fuel Pressure Regulator working within spec, fuel pump creating PSI within spec and leak down pass or fail (all injectors at once).
Your compression test:
No big concerns on cylinder compression. Many engine with similar low compression and, but your differential a bit high.
I see compression above the minimum PSI of 142PSI. But all low, with #1 150PSI & #2 172PSI. Which is fail in differential of 14PSI spec. With a 22PSI differential. I do not see wet test.
I see cylinder leak down test done at ~30PSI. I do them at ~90PSI. I do not see notes on where down leak i.e. rings, valves, head gasket.
We also don't know how fast mechanic to, beginning test after shut down, nor RPM or if he had throttle body wide open. But let us assume, he did by the book.
The differentials in PSI. Tends to make idle a bit rough. BK2 runs leaner (LTFT2 higher by ~4%), BK1 slightly less correcting as shown by LTFT1 to richen mixture. Makes some sense, based on cylinder (compression) balance. This could account for idle not being steady. But until LTFT bought in line. I'd not make to much of idle RPM variance.
Your vacuum test, indicated no vacuum leak: So' id move on to fuel starvation testing.
BTW: Just as a point of interest. The VVTi 4.7l upstream, is actually a A/F sensor, not o2.
FWIW: I'll be running a fuel pressure test & cylinder compression test today. Mostly to collects data.
On a 23,500 miles 2007 LC VVTi. More to collect data, on lowest miles Land Cruiser know in USA. As reference points, but also part of base line restore. Since, super low miles, can and do have issues. Fuel system related issues, mostly.
I'm getting a little "D" vibration, which is talk about in this forum. Engine runs a bit rough at 2,000 RPM (stationary in park). On HWY, at over 4,500 RPM. It has a bit of an oscillating droning sound.
It's, fuels trims are good. But I feel could be a bit better, for engine barely broken in. It may have some spray pattern issues. I'll be sending them out to be tested by FIS. Then we'll know without any doubt.
Idling
Flat HWY steady RPM & speed
I'll also R&R fuel filter. Then blowing-out on bench. To see if clean or dirty backflush. The vehicle came from small rural city. Which we see more old gas station, with old metal tanks. If filter, shows signs of dirty fuel. I'll then go deeper and inspect fuel tank/pump.
On this 07LC. I did find one concerning issue. Muck in fuel filler door/cap area. Fuel cap letter unreadable. This points to fuel boiling, where fuel comes out the cap. Which was likely caused by, overfilling gas tanks (100 series 03-07 issues). Which both overfilling & boiling, floods the charcoal canister. The EVAP system can also, cause fuel trims issue.