Could my throttle body be the culprit?
07-28-14, 07:09 PM
#31
Pole Position
Thread Starter
You guys wow wow, first off don't just start taking sensors off and random things and start spraying them out... I've gone through this exact same issue A FEW TIMES! And each time was a different issue that brought up the same codes, pointing at the same stuff, when in fact, it wasn't. First off the TPS has to be installed correctly checking it's voltage to calibrate accordingly. But, first off, oil in the plug ports could also be from the plug seals themselves which is very common, but a bit of work to replace. But for the VSC On/VSC/Off light being on, the following could be, were my! Issues. My battery was trash, and turned out my alternator was bad as well, once I changed those both, solved my problem for over a year. Now I don't care if you think your battery is good, or if you just purchased it, because check it out, I had just bought my battery too, and when someone told me I was reluctant to consider, and it ended up being so. These battery's can be shelved for god knows how long, but if put into a car with a garbage alternator, well then that's just a road to success for failure lol. Then a year or so later it came back, I installed a new TPS sensor, issue went away but not for long. It came back, in the end, what ultimately solved my issue was when I tried swapping out my entire throttle body with another I had, everything went away. Before I did so, I replaced the dam motor, I replaced almost everything that could be replaced on the TB it's self. I've got a huge thread on it but I believe it's on lexusownersclub let me take a look.
MH: Another point to consider. I see your car is 1998. I believe the throttle system you describe is similar to mine. (2002) This is a fully electronic fly-by-wire system. The TPS takes position readings from your pedal position. There is a throttle motor that turns the butterfly in the throttle body, as commanded by the ECM. Everything is mounted on top of the engine, so a cable is necessary to the pedal. As a secondary consideration, there is partial movement of the butterfly through the pedal linkage. In case of a flooded (with gasoline) condition, this allows the driver to crank the engine, supplying air with the throttle wide open. In no case should the engine be expected to perform without an operating throttle motor.
07-28-14, 08:00 PM
#32
Pole Position
Thread Starter
Just checked everything again. Apparently there was something loose causing the butterfly valve to stay open. But its still in limp mode. I can get it to idle, and the traction lights will come on and off.
Question for the gurus. Would a TPS sensor that is not calibrated to the correct voltage at idle (I'm assuming .65-.72 volts at idle?) Cause the car to quickly go into limp mode? i notice when i hit the gas every half second or so, it will kick in and out. Im wondering if this is all being caused by a non-calibrated TPS. I was reading somewhere where someone said to calibrate the TPS to those numbers, and then turn the car off. rest ECU (or unplug the TPS) for a short amount of time, and then start the car, if it goes straight to limp mode try again until its cal'ed right. If that doesn't work. A possible new ECU is in order i guess.....I will get the TPS to the right voltage and try to reset the ECU and hopefully it will notice the correct value and not sit in limp mode.
Question for the gurus. Would a TPS sensor that is not calibrated to the correct voltage at idle (I'm assuming .65-.72 volts at idle?) Cause the car to quickly go into limp mode? i notice when i hit the gas every half second or so, it will kick in and out. Im wondering if this is all being caused by a non-calibrated TPS. I was reading somewhere where someone said to calibrate the TPS to those numbers, and then turn the car off. rest ECU (or unplug the TPS) for a short amount of time, and then start the car, if it goes straight to limp mode try again until its cal'ed right. If that doesn't work. A possible new ECU is in order i guess.....I will get the TPS to the right voltage and try to reset the ECU and hopefully it will notice the correct value and not sit in limp mode.
07-28-14, 08:01 PM
#33
Pole Position
Thread Starter
Im pretty sure that the Traction Control lights coming on and off could be from the voltages not being correct. Im not positive, but i thought the Traction system was incorporated with the TPS for measurements on throttle, and to gauge traction and what not. i could be wrong though.
07-28-14, 09:10 PM
#34
Pole Position
Thread Starter
http://my.is/forums/f115/cel-driving...ircuit-431571/
I was using this as reference, but am still insanely lost. I really don't get why the **** I'm not getting anything. I checked the sensor on its own, and was at a consistent 1.3V.....so according to the diagram, the TPS needs to be replaced.
But when I was following the initial directions just to calibrate the TPS i was moving it around and nothing happening. I was doing VTA to ground just like it says to and was moving the TPS around and not really getting anything. Is my Multimeter to sensitive enough to get such a low voltage? I will buy someone a 30 pack if they can help me figure this out.
I was using this as reference, but am still insanely lost. I really don't get why the **** I'm not getting anything. I checked the sensor on its own, and was at a consistent 1.3V.....so according to the diagram, the TPS needs to be replaced.
But when I was following the initial directions just to calibrate the TPS i was moving it around and nothing happening. I was doing VTA to ground just like it says to and was moving the TPS around and not really getting anything. Is my Multimeter to sensitive enough to get such a low voltage? I will buy someone a 30 pack if they can help me figure this out.
07-29-14, 07:41 PM
#35
Driver School Candidate
MH: If you are measuring the voltage on VTA and rotating the TPS but the voltage stays at 1.3V, then yes something is wrong. The voltage should begin to change when the sensor is rotated CCW and after it touches the throttle valve shaft. You should get something over 4.50 volts when the throttle valve shaft is moved to wide open throttle. VTA2 should track similarly, with about 1.50 volts more than VTA. The ECM is monitoring both voltages. The voltage measurement should change smoothly without any dropouts.
What are you using to check voltage? Your DMM needs at least 2 digits behind the decimal point to measure accurately enough (hundredths of a volt).
What are you using to check voltage? Your DMM needs at least 2 digits behind the decimal point to measure accurately enough (hundredths of a volt).
07-31-14, 07:20 PM
#36
Driver School Candidate
MH: Try checking the TPS using your ohmmeter and the illustration "check throttle position sensor" from the post by digger08. But first, unplug and take the TPS off the vehicle. As you check resistance, VC to E2 resistance should not change as the TPS is rotated. (You can't rotate the TPS while mounted on the car.) Next, check VTA to E2 and then VTA2 to E2. You should see a smooth change in resistance for both tests as the shaft is rotated. If you see 0.00 ohms or OL at any time, then yes the TPS has a problem. Keep us posted.
07-31-14, 08:05 PM
#37
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Not saying this is what it is, but aside from the voltage checks and what-not, but split intake hoses on these things can cause some crazy drivability concerns (with no codes- because fuel trim is 2 trip logic.) Especially when its on the bottom where you can't see it. Some of the simplest crap can make you over think diagnostics.
Cruising along towards the sunset and then you lay on it to impress your lady then BAM! kickdown on your tranny coupled with worn mount and that hose spreads at a point past the MAF.....just saying....
Cruising along towards the sunset and then you lay on it to impress your lady then BAM! kickdown on your tranny coupled with worn mount and that hose spreads at a point past the MAF.....just saying....
08-01-14, 06:05 AM
#38
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I have made the mistake of listening to the dealership troubleshooting they told me the front right ABS wheel speed sensor was bad but in fact that was not the culprit (it was soldered back together in the past) and now in addition to the beeping sound with the traction light I also have a new front right ABS speed sensor installed and due to the fact my car is from the north I'm assuming the rust has caused a bad connection so now I have the group of lights on the dash in addition to the car throwing the two infamous codes for abs and front right speed sensor VSC and ABS lights are on. So instead of one problem now I have two. This is very annoying. any help appreciated. I see the comments on the battery and the alternator my battery actually was changed a couple weekends ago I went with a diehard platinum battery and my alternator was changed out about 9 months ago and I went with a denso alternator. they did check to make sure the alternator worked. Will have the TPS sensor and the hoses checked out as part of the fuel clean up was to clean up the hoses so maybe they did not put things back right.
Last edited by iamkhanz; 08-01-14 at 06:23 AM.
08-01-14, 02:17 PM
#39
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update mechanic seems to think my issue is the ABS pump assembly that includes the master cylinder... grab one from the junkyard andguy says these go out a lot on the GS 300... I'm keeping my fingers crossed let's see what happens will update you guys. Also mechanic did take a look at the TPS sensor and all those other items and felt everything was okay.
08-01-14, 09:23 PM
#40
Pole Position
Thread Starter
update mechanic seems to think my issue is the ABS pump assembly that includes the master cylinder... grab one from the junkyard andguy says these go out a lot on the GS 300... I'm keeping my fingers crossed let's see what happens will update you guys. Also mechanic did take a look at the TPS sensor and all those other items and felt everything was okay.
08-02-14, 07:48 AM
#41
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Abs controller master cylinder is changed out I have bled all 4 sides of the wheels and still when I brake completely it makes the sound of ABS going off for a second and it sounds like it's sliding on ice for a second. Not sure what the cause of this is now. Any clues guys?
Speed sensor changed
throttle position sensor looked at
master cylinder changed
no resolution. Man I'm tempted to buy another BMW... Lexus isn't suppose to have problems!!!
Speed sensor changed
throttle position sensor looked at
master cylinder changed
no resolution. Man I'm tempted to buy another BMW... Lexus isn't suppose to have problems!!!
Last edited by iamkhanz; 08-04-14 at 02:10 PM.
08-03-14, 09:10 AM
#42
Pole Position
Thread Starter
might want to clean up your comment and make it a bit more clear. its a little difficult to tell whats going on in a couple spots.
But quick update on mine. So after setting the TPS to .70, and cleaning and checking everything, the car went back to normal. well today i decided to do some "Spirited" driving through some canyons. She was doing well, traction light kicking in at a couple hairy spots as expected, but when i got about 30 seconds into it, with some aggressive throttle, it went into limp mode again. So i slowed it down, and after 5 seconds of normal driving it went right back to normal. So I'm not sure if this is the TPS showing signs of taking a ****, but when that happened the Traction lights came back on. This is such a crazy annoying thing. Im very motivated to find the problem lol
But quick update on mine. So after setting the TPS to .70, and cleaning and checking everything, the car went back to normal. well today i decided to do some "Spirited" driving through some canyons. She was doing well, traction light kicking in at a couple hairy spots as expected, but when i got about 30 seconds into it, with some aggressive throttle, it went into limp mode again. So i slowed it down, and after 5 seconds of normal driving it went right back to normal. So I'm not sure if this is the TPS showing signs of taking a ****, but when that happened the Traction lights came back on. This is such a crazy annoying thing. Im very motivated to find the problem lol
08-04-14, 02:11 PM
#43
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I've updated it, sometimes while typing on phone it does some auto correcting.. Latest today they are flushing the brake fluid.. I'm not sure what that will do as I basically flushed it when I did the bleeding of brakes other day. Wish there was a mechanic in Houston that had seen this problem before... argh
08-04-14, 02:25 PM
#44
Pole Position
Thread Starter
unfortunately it seems that there is no consistency with this problem on the gs300. Everyone seems to find a different defective part with the same issues. A lot of trial and error, and a lot of troubleshooting is a pain in the ***, but at least you know what the F is going on with the system after. lol Mine is still ghostly popping up under heavy throttle, again with no codes. Im leaning towards the TPS itself slowly failing. Once i locate where the traction control wires go to then i will know the plug and can hopefully narrow it down that way.
08-05-14, 02:26 PM
#45
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Mechanic change took it to Stereo EFX and they replaced spindle / cv shaft and are claiming its fixed now...
From what ekse I read
To fix the issue - do a search in the Rx Forums - for "tone ring."
The ABS tone ring is a "gear-like" wheel that sends the electrical impulses to the abs sensor to measure. When the car gets older - the metal in the knuckle rusts, and pushes a metal liner into the tone ring - destroying it.
This makes the ABS sensor read incorrectly - and activates the ABS everytime you brake.
I will say - NO ONE - at all - sells the ring. So if this is the issue - you're going to have to do what I did and replace the entire CV Axle - as the ring is built into it. Also, the metal liner will need to be replaced also - this is approx a $10part from toyota. The real expense is the axle. If you want a new one - it's $500, and they are in very limited supply. When mine went - there was ONE new unit in the whole USA.
I believe this is your issue. Hope I am some help to you.
https://www.clublexus.com/forums/sus...any-ideas.html
From what ekse I read
To fix the issue - do a search in the Rx Forums - for "tone ring."
The ABS tone ring is a "gear-like" wheel that sends the electrical impulses to the abs sensor to measure. When the car gets older - the metal in the knuckle rusts, and pushes a metal liner into the tone ring - destroying it.
This makes the ABS sensor read incorrectly - and activates the ABS everytime you brake.
I will say - NO ONE - at all - sells the ring. So if this is the issue - you're going to have to do what I did and replace the entire CV Axle - as the ring is built into it. Also, the metal liner will need to be replaced also - this is approx a $10part from toyota. The real expense is the axle. If you want a new one - it's $500, and they are in very limited supply. When mine went - there was ONE new unit in the whole USA.
I believe this is your issue. Hope I am some help to you.
https://www.clublexus.com/forums/sus...any-ideas.html