Warning lights (1 Viewer)

I'm hoping you guys can help me figure out what's wrong. Here's the sequence of events:

-Engine running a bit rough at idle, just for a couple seconds at a time, about once a month for 3-4 months

-It's been getting more frequent for the past 2 weeks

-Since putting gas in last night, it's rough at idle every time I come to a stop

-Tonight on the way home from work, the "check engine" light starts to flash, then eventually burns steadily

-The "VSC TRAC" and "VSC OFF" lights (both yellow) come on and stay on

-Until tonight, the engine would always smooth out over 1000 rpm; tonight it started running rough at higher rpm also

One other thing that may or may not be related: I got the PCV valve changed a month ago at the 90K (as well as everything else) and since the service, whenever I really lay on the gas and the engine's b/t 3-4000 rpm, it's got this loud whistling sound that drops in pitch as the engine speeds up. May or may not be related, but it makes me wonder about the installation of the PCV valve and whether this may all be connected. OTOH, the rough idle predates the 90K svc.

I always use Shell 93, if that matters.

Something remotely similar used to happen in my car a while back. It felt like the engine was gasping for air.

Turned out that I had a cracked air intake hose. Once I changed it, the problem was fixed. Might not be a similar problem, but I wanted to share my experience with you.

I have had similar problems.
Check the valves and make sure they are tight. then check your gas cap. Most common culprit. Make sure the seal is solid and tight. I would take it to autozone and have them do a free test. 90% of the time it is the gas cap.

Did you have an induction service done??? If so then maybe they freed up some junk that needs to be burned out. If it blocks the oxygen sensors or gets in the way it will turn on the light.

You can do all the maintinance, use 93 and still have problems if you use it as a daily driver in stop and go.

If you haven't done an induction service, then you might wish to either get it done, or buy some sea-foam (6.00)and unplug the hose going to the PCV valve and pour it in slowly. Follow the directions on the bottle. Your engine will run alot smoother. I put it in the valve, then the gas tank and the oil right before and change. It gets treated very well, best gas/oil etc and the smoke still came billowing out of the back, lasted a short time and then I drove it, the engive was very wierd for about a week, making funny noises, kicking out a little smoke here and thier. Then about two weeks after the Check engine light came on. with trac etc. I took it in and the guy said that this was common with older LC/LX that do stop and go, carbon builds up pretty badly. he ran the tests and the diagnoses was either a dirty/bad sensor. he said if it runs and sounds better than before, performance is enhanced, most likely it is just dirty. Since we don't have an official fix for this I can't charge you unless I replace it. But you can go down the street and buy some break cleaner. Take out the sensor that has two screws on top that is right next to the air filter. hold it out with a pair of pliers and spray it clean, make sure you get it down on the sensor. Let it air out, and replace it. then unplug the battery and to reset, and you should be good to go. I was. the small glass filament in the sensor was stubborn, and brown. when I was done, 1/2 bottle later, it was clear. So far everything works well. I hope this is your fix too. If not let us know and we can see. If you need pics pm me.

Easiest way to reset the Light is to unscrew the battery. Anytime the Check engine Light comes on in a Toyota/Lexus product the Traction Control is automatically turned off.

Check and see if the air filter is leaking.

The CEL code will probably tell the story.

Thanks for the input guys. JIJ, is this a sensor on the induction housing, after the air filter? I may take a look at that first. Unfortunatley I'm going out to WA this morning and won't get back till Sunday night, so I will probably tackle it then.

Glad to hear the VSC lights come on with the CEL, that one worried me a bit.

DoctorJay said:

Thanks for the input guys. JIJ, is this a sensor on the induction housing, after the air filter? I may take a look at that first. Unfortunatley I'm going out to WA this morning and won't get back till Sunday night, so I will probably tackle it then.

Glad to hear the VSC lights come on with the CEL, that one worried me a bit.

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I bet you money with that whistling noise at higher speeds you have a leak either the airfilter is not seated correctly or a leak/crack in the air intake hose that might of happen when they were working on you LC.

yes, that is the sensor. Let me know is this helps.

Update

Well, Plan A failed. (That's the one where I leave town for a few days, and hope the truck sorts itself out while I'm gone. Usually ineffective but always cheap).

I tried JIJ's idea, and pulled the sensor on the intake duct downstream from the air filter (Plan B). It looked fine, there was no dirt/grime/corrosion that I could see, so I just put it back. Now my LC is riding a flatbed to the mechanic (Plan C). We'll see what he finds.

DoctorJay said:

Well, Plan A failed. (That's the one where I leave town for a few days, and hope the truck sorts itself out while I'm gone. Usually ineffective but always cheap).

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LOL - What's suprising is how often this works!

Sorry to hear about the tow.

NMuzj100 said:

LOL - What's suprising is how often this works!

Sorry to hear about the tow.

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I thought that was my exclusive plan...

Funny thing. The mechanic gets it this AM and it runs all rough on the test drive. The engine diagnostics give the following codes:

P0300 - multiple misfire
P0302 - cyl #2 misfire
P0307 - " " #7
P0308 - " " #8

Well, no s***. It's misfiring.

Then the thing starts running fine except for a couple of moments where it idles rough. So my mechanic calls me and tells me about what's going on, and how this makes the diagnosis so much harder. He quoted me $89 for the dx yesterday and when I balked, he told me how hard these dx's can be sometimes. Long story short, he now says he wants $189-249 just for the dx.

I told him to let it run for a bit and see if it roughens up a bit again. I think that price is ridiculous for a diagnostic, and besides the whole point of charging $89 is that it's sort of like insurance: if it's a chip shot O2 sensor, they come out ahead; if it's tough (like this) I do.

Just off the phone again.

Apparently the p0307 code keeps coming up, but so do the others. Good spark, good signal to the injector, but the oscilloscope is flatline on the injector. He wants to do a fuel system/combustion chamber cleaning ($150) and probably replace the #7 injector ($490). I told him to do the cleaning first; if the injector's bad, there's nothing lost, if it's salvageable, I save $500.

What's troubling me is that there are multiple misfires and I can't imagine there are 3 bad injectors all at once, nor can I see how one bad injector is causing all this trouble.

I'd love to hear any thoughts y'all have...

Unfortunately these codes have a number of possible causes

I wonder why he wants to replace the #7 injector but not the others. What is involved in a Fuel system/combustion chamber cleaning ? (a bottle of techron/BG44K?)

the FSM lists the following trouble areas.
-Ignition
-Injector
-Fuel line pressure *1 (gas cap,fuel filter and fuel pump [pump,relay,circuit and ECU D-121])
-Compression
-Valve Clearance
-Mass Air flow sensor *2
- Engine Coolant sensor *2
- Open or short in engine wiring *
- Connector connection
- ECM *

I placed a star next to the ones I would focus on because they would more likely effect multiple cylinders at the same time. I would check the three I numbered first in that order because they should be easy to check.

Thanks for the input NM. These are a lot like what he mentioned as well:

-plug wires
-coil
-crank position sensor
-cam " "
-EGR valve
-fuel system

He recommended replacing the #7 injector b/c it was a flat line on the oscilloscope, meaning dead. Frankly, he (my mechanic) and I (a surgeon) do essentially the same thing. Diagnose and repair. So I'm still thinking the injector can't really be dead, because it doesn't explain the misfires in #2 and #8 at all. He had trouble with that one too. All of which makes me think that this may be a dirty intake system, or some kind of sensor with an intermittent problem.

And we haven't done the fuel or other diagnostics, because that just gets us back to arguing about spending $250 on a diagnostic. Anyway, I'll run your list past him and see what he says, thanks again.

BTW, the fuel system cleaning involves removing the fuel line at some point and hooking the fuel rails up to a machine that injects a cleaning solution through them and the injectors and combustion chambers.

DoctorJay said:

Thanks for the input NM. These are a lot like what he mentioned as well:

-plug wires
-coil
-crank position sensor
-cam " "
-EGR valve
-fuel system

He recommended replacing the #7 injector b/c it was a flat line on the oscilloscope, meaning dead. Frankly, he (my mechanic) and I (a surgeon) do essentially the same thing. Diagnose and repair. So I'm still thinking the injector can't really be dead, because it doesn't explain the misfires in #2 and #8 at all. He had trouble with that one too. All of which makes me think that this may be a dirty intake system, or some kind of sensor with an intermittent problem.

And we haven't done the fuel or other diagnostics, because that just gets us back to arguing about spending $250 on a diagnostic. Anyway, I'll run your list past him and see what he says, thanks again.

BTW, the fuel system cleaning involves removing the fuel line at some point and hooking the fuel rails up to a machine that injects a cleaning solution through them and the injectors and combustion chambers.

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With more than one cylinder misfiring, it does not seem like a fuel injector issue, does it? Maybe an induction service is not a bad idea to start with.

DoctorJay said:

Thanks for the input NM. These are a lot like what he mentioned as well:

-plug wires
-coil
-crank position sensor
-cam " "
-EGR valve
-fuel system

He recommended replacing the #7 injector b/c it was a flat line on the oscilloscope, meaning dead. Frankly, he (my mechanic) and I (a surgeon) do essentially the same thing. Diagnose and repair. So I'm still thinking the injector can't really be dead, because it doesn't explain the misfires in #2 and #8 at all. He had trouble with that one too. All of which makes me think that this may be a dirty intake system, or some kind of sensor with an intermittent problem.

And we haven't done the fuel or other diagnostics, because that just gets us back to arguing about spending $250 on a diagnostic. Anyway, I'll run your list past him and see what he says, thanks again.

BTW, the fuel system cleaning involves removing the fuel line at some point and hooking the fuel rails up to a machine that injects a cleaning solution through them and the injectors and combustion chambers.

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Damn sorry about your problem but man it is hard to fight over the higher DX charge. I'm sure if a patient calls and says he is having XYZ pain/problem and wants to know what you will charge to fiqure out what is wrong with him you don't quote 1 office call??? You tell him to come in and your will start running tests until you figure it out and he will have to pay based on the amount of time it takes. At a hell of a lot higher rate then this guy is charging. If your a Surgeon just have it towed to the Lexus dealership and trade it for a new LX470

SWUtah said:

If your a Surgeon just have it towed to the Lexus dealership and trade it for a new LX470

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Haha.....

SWUtah said:

Damn sorry about your problem but man it is hard to fight over the higher DX charge. I'm sure if a patient calls and says he is having XYZ pain/problem and wants to know what you will charge to fiqure out what is wrong with him you don't quote 1 office call??? You tell him to come in and your will start running tests until you figure it out and he will have to pay based on the amount of time it takes. At a hell of a lot higher rate then this guy is charging. If your a Surgeon just have it towed to the Lexus dealership and trade it for a new LX470

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A couple of points, and I do mean this respectfully:

1. I'm a resident for the next year, so I'm on a salary that's probably on the low end of the 100 board

2. When I'm out in practice, I won't be quoting prices for my work. That's what insurance is for.

3. Surgeons get paid for the operation, period. Then there's something called a "90-day global." That means that they assume the patient's surgical care, follow-ups, returns to the OR, etc, without additional reimbursement.

Please knock off the new Lexus, rich-surgeon thing. I'm not rich, and if I'm an a******, it's not because I'm a surgeon. I'm pissed off that I just wrote this guy a check for over a grand for the 90K (labor only) and I'm getting no love from him right now. And I just don't see a new $500 injector fixing a problem in 3 cylinders, and I don't think he does either. If the dx is going to cost $250, fine, just don't fxxxing tell me it's going to cost $89 and then triple it when you can't figure it out in 15 minutes.

Peace.

DoctorJay said:

A couple of points, and I do mean this respectfully:

1. I'm a resident for the next year, so I'm on a salary that's probably on the low end of the 100 board

2. When I'm out in practice, I won't be quoting prices for my work. That's what insurance is for.

3. Surgeons get paid for the operation, period. Then there's something called a "90-day global." That means that they assume the patient's surgical care, follow-ups, returns to the OR, etc, without additional reimbursement.

Please knock off the new Lexus, rich-surgeon thing. I'm not rich, and if I'm an a******, it's not because I'm a surgeon. I'm pissed off that I just wrote this guy a check for over a grand for the 90K (labor only) and I'm getting no love from him right now. And I just don't see a new $500 injector fixing a problem in 3 cylinders, and I don't think he does either. If the dx is going to cost $250, fine, just don't fxxxing tell me it's going to cost $89 and then triple it when you can't figure it out in 15 minutes.

Peace.

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Did not realize you were a resident, changes my comment until next year . If this is a dealership I would be talking to the service manager, but it sounds like you are dealing with a local shop. If they think you are a MD you might be getting the old milk him for all he is worth routine or you just have a guy that is a decent machanic but a poor business man and he feels justified to charge you for his work even though he quoted you $89. You have the option of driving it to the local dealership and have them take control.