Throttle Body Replacement

[oohryry]

Anyone know where I can purchase a 98 LS throttle body besides the dealership?

Also, can cleaning them solve the problem? My check engine light comes on again and puts the rpm's at 2000 automatically. So I have to cut off the car and restart it to get control of the acceleration again. I left my a/c running all the time so I wouldn't have this problem, if you notice the a/c changes the tension in the throttle, but now that the temperature is freezing, the LS automatically shuts off the a/c because it is freezing outside. It will stay on if it's at least 40 degrees. I don't know anything about the throttle body or it's function so I don't know if cleaning it will solve this problem.

Thanks everyone.

[highlander]

get it scanned and check the DTCs.

[prix]

Just returned from a visit to my genius indie mechanic, and we discussed at some point replacing the throttle body assembly on my 94LS400 (to fix the low engine idle problem and stall outs). This would cost (including labor) in ballpark of $800 or so, I think (not certain). Anyhow, this guy knows everything. You should feel free to call him for a quick discussion, and see if he has any parts he can sell you...(if that's what he suggests): He should be in the directory: Foothill Independent in La Crescenta, California. Name is George. Feel free to send me an email if you cannot find the number (or repost here) and I'll look it up for you.

Anyone know where I can purchase a 98 LS throttle body besides the dealership?

Also, can cleaning them solve the problem?  My check engine light comes on again and puts the rpm's at 2000 automatically.  So I have to cut off the car and restart it to get control of the acceleration again.  I left my a/c running all the time so I wouldn't have this problem, if you notice the a/c changes the tension in the throttle, but now that the temperature is freezing, the LS automatically shuts off the a/c because it is freezing outside.  It will stay on if it's at least 40 degrees.  I don't know anything about the throttle body or it's function so I don't know if cleaning it will solve this problem.

Thanks everyone.

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[cardona6569]

Anyone know where I can purchase a 98 LS throttle body besides the dealership?

Also, can cleaning them solve the problem?  My check engine light comes on again and puts the rpm's at 2000 automatically.  So I have to cut off the car and restart it to get control of the acceleration again.  I left my a/c running all the time so I wouldn't have this problem, if you notice the a/c changes the tension in the throttle, but now that the temperature is freezing, the LS automatically shuts off the a/c because it is freezing outside.  It will stay on if it's at least 40 degrees.  I don't know anything about the throttle body or it's function so I don't know if cleaning it will solve this problem.

Thanks everyone.

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Having the TB clean won't cost you too much. Start troubleshooting there; the suggestion of scanning the car is not a bad one either, because you said the Check engine keeps coming on, so it means something in the system is out of specification.

Keep us posted!

C. PR

[nc211]

Yeah man, don't go buy a new one if you haven't had your existing one cleaned yet. You just might find your existing one is so dirty, but still fine, that all it needs is a bath. You have to take it off anyway if you are going to replace it with a new one...might as well just clean it for $10 bucks in cleaner and see what happens, instead of coughing up a few C' notes for a new one. I'm thinking if you're getting the light, then it's probably something else down the line that's causing your problem instead of a dirty throttle body. How about your air intake sensor, or throttle sensor? I think those "especially the throttle sensor" would be a more likely canidate. I know on my 95' with 109k my throttle sensor was replaced by the previous owner at the dealer right around 70k miles. As far as I know, the throttle body itself has never been touched, and I've never had the engine light come on....of course now that I've said that...oh crap...here it comes.

God, Santa, please let me get the new tires first and a week of enjoyment before you smack me with the O2 sensors or something like that.

[Threadcutter]

Oohryry:

Here's a contact that I've used recently. Seems pretty decent.

Toyolex Parts Connection, fsartore@toyolexparts.com,

Tel: 352-243-9705, Fax: 352-243-9706.

BUT.......I wholeheartedly agree with nc211's response of "Yeah man, don't go buy a new one if you haven't had your existing one cleaned yet". The throttle body is a cast aluminum "duct" that is bolted onto the air intake chamber/intake manifold. As nc211 states, it has the Throttle Position Sensor mounted on the side of it.

Check out this link, it will give you a very good idea of what everything looks like and what is involved;

http://www.lexls.com/tutorials/EFI/throttlebody.html

It should be apparent that the cleaning of the throttle body is the easiest part of the whole procedure. Unless there is some kind of physical damage to the throttle body, there is no reason to replace it (unless you're asking the stealer (who only wants to sell you new parts)). Save your money and invest it in a code reader instead. I did and it's great not being at the mercy of those who would deprive me of my paycheck(s) or firstborn.

[monarch]

Toyota throtlle bodies are designed to last the life of the vehicle. I've got 467,000 miles on one mine without a whimper of trouble, but I do clean the throttle plate regularly.

[nc211]

I have never done this, but am curious about doing it. Do you really notice a big difference after you clean it in the car's performance?

[oohryry]

Just returned from a visit to my genius indie mechanic, and we discussed at some point replacing the throttle body assembly on my 94LS400 (to fix the low engine idle problem and stall outs).  This would cost (including labor) in ballpark of $800 or so, I think (not certain). Anyhow, this guy knows everything.  You should feel free to call him for a quick discussion, and see if he has any parts he can sell you...(if that's what he suggests):  He should be in the directory:  Foothill Independent in La Crescenta, California. Name is George.  Feel free to send me an email if you cannot find the number (or repost here) and I'll look it up for you.

Anyone know where I can purchase a 98 LS throttle body besides the dealership?

Also, can cleaning them solve the problem?  My check engine light comes on again and puts the rpm's at 2000 automatically.  So I have to cut off the car and restart it to get control of the acceleration again.  I left my a/c running all the time so I wouldn't have this problem, if you notice the a/c changes the tension in the throttle, but now that the temperature is freezing, the LS automatically shuts off the a/c because it is freezing outside.  It will stay on if it's at least 40 degrees.  I don't know anything about the throttle body or it's function so I don't know if cleaning it will solve this problem.

Thanks everyone.

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Dude, I'm in Maryland. I love the fact that I put my Lex on 153 mph, but they can't fly just yet. But thanks anyhow. Let me know if he's visiting Maryland anytime soon.

[oohryry]

Anyone know where I can purchase a 98 LS throttle body besides the dealership?

Also, can cleaning them solve the problem?  My check engine light comes on again and puts the rpm's at 2000 automatically.  So I have to cut off the car and restart it to get control of the acceleration again.  I left my a/c running all the time so I wouldn't have this problem, if you notice the a/c changes the tension in the throttle, but now that the temperature is freezing, the LS automatically shuts off the a/c because it is freezing outside.  It will stay on if it's at least 40 degrees.  I don't know anything about the throttle body or it's function so I don't know if cleaning it will solve this problem.

Thanks everyone.

←

Having the TB clean won't cost you too much. Start troubleshooting there; the suggestion of scanning the car is not a bad one either, because you said the Check engine keeps coming on, so it means something in the system is out of specification.

Keep us posted!

C. PR

←

I took it to Lexus of Towson and had them perform the scan. That's how I know it's the throttle body. I think it was code 935 or something like that, but they told me that was causing the check engine light and VSC to illuminate. I'm going to try and have it cleaned next Friday. I'm spending all my money this week on my starter. The starters on the 95-97 were recalled. That didn't help me much.

[oohryry]

Yeah man, don't go buy a new one if you haven't had your existing one cleaned yet. You just might find your existing one is so dirty, but still fine, that all it needs is a bath. You have to take it off anyway if you are going to replace it with a new one...might as well just clean it for $10 bucks in cleaner and see what happens, instead of coughing up a few C' notes for a new one. I'm thinking if you're getting the light, then it's probably something else down the line that's causing your problem instead of a dirty throttle body. How about your air intake sensor, or throttle sensor? I think those "especially the throttle sensor" would be a more likely canidate. I know on my 95' with 109k my throttle sensor was replaced by the previous owner at the dealer right around 70k miles. As far as I know, the throttle body itself has never been touched, and I've never had the engine light come on....of course now that I've said that...oh crap...here it comes.

God, Santa, please let me get the new tires first and a week of enjoyment before you smack me with the O2 sensors or something like that.

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nc, man you're funny. I think the place wants about 100.00 to clean the throttle body. I can't do it myself because I don't even know where or what it looks like, let alone what it's for. I imagine that it's the body of a throttle as Martin Lawrence might put it.

[oohryry]

Thanks Threadcutter, but that looks like a whole lot of work to clean the throttle body. I'd rather spend the 100.00 and hope they clean it as good as the tutorial was done. Thanks again. If I need to change the throttle body then I probably would do this considering the big difference in cost it would definitely be worth it then. However, don't know anywhere to purchase a throttle body for an LS400.

[nc211]

www.lexuspartsonline.com

Thanks Threadcutter, but that looks like a whole lot of work to clean the throttle body.  I'd rather spend the 100.00 and hope they clean it as good as the tutorial was done.  Thanks again.  If I need to change the throttle body then I probably would do this considering the big difference in cost it would definitely be worth it then.  However, don't know anywhere to purchase a throttle body for an LS400.

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[morg96ls400]

Throttle body was easy to clean, mine only had a thin layer of grime on it, but after cleaning the change was very noticable. The car was more responsive, felt less sluggish than it had prior to the cleaning.

My car is a 96 LS but the procedure should be fairly similar:

BE PREPARED: about 1.5 hrs, buy a new TB gasket from dealer (about 2-3 bucks), and a can of TB cleaner ( I Used valvoline synthetic, worked very well.

Getting to the throttle body:

Remove all the plastic covers off the engine and fan, disconnect the maf sensor, remove the air filter and intake. You will see the clean side of the throttle body after you remove the plastic intake.

Throttle body removal:

First you need to disconnect the throttle cables. I was confused on how to do this, but I then figured it out. There are three, and in order to get them off you have to manually move the metal throttle part back so you can get some slack in the cable itself, and then remove it from the the throttle by pushing it out while clearing the cable of the notch. Do this for all three cables, each one having its own little way of moving the cable around to free them, and then you can proceed to removing all the hoses, throttle sensor, and four bolts that hold the throttle body onto the engine.

TIP: In the .PDF for removing the throttle body, it says to drain the coolant from the radiator. THIS IS NOT NECESSARY. Just remove the radiator cap to release excess pressure in the system, and when you remove the two radiator hoses that go onto the throttle body just cover them (I used a rubber glove held on with a rubber band).

TIP: For the hoses, most will have never been taken off before, and will seem like they will NEVER come off. This is where good ol' WD40 and a flathead screwdriver come in handy. Use the small flathead to wedge it between where the hose and throttle body couple, and spray some WD40 into the opening you make. This should start the process of loosening the hose, and enough prying and spray will end up with the hose sliding off quite easily, just be patient. Take all of the hoses off before you remove the four bolts, or you will have trouble getting them off.

After all the hoses are off the throttle body, remove the four bolts with a deep socket and remove the throttle body. The gasket will probably need to be pryed off as it should be pretty dried out. clean the mating suface before you put the new gasket on.

Use your throttle body/intake cleaner and spray it liberally onto all the black gunk you see. You should be able to clean inside the engine side once you take off the throttle body. I used a screwdriver with paper towels wrapped around the end to clean as far as I could reach inside the intake chamber. I sprayed the cleaner everywhere inside and let the cleaner soak several times. After I was done everything was shiny clean and dry. I reassembled the throttle body and put everything back on in the same order. I also noticed the shrink plastic covering on the throttle sensor wires was deteriorated and dried out, i took that off and used some duct tape to cover them up and protect them from being damaged.

-After startup, the rpms will be high for a bit until the residual tb cleaner is burnt up from the AIC, so don't be alarmed, just let the system burn it.

Overall about an hour and a half of work, well worth it. Save the hundred bucks and have some fun with your car. Spend the money on the wife, good luck!

remo.pdf

comp.pdf

torspe.pdf

[Threadcutter]

Thanks Threadcutter, but that looks like a whole lot of work to clean the throttle body. I'd rather spend the 100.00 and hope they clean it as good as the tutorial was done. Thanks again. If I need to change the throttle body then I probably would do this considering the big difference in cost it would definitely be worth it then. However, don't know anywhere to purchase a throttle body for an LS400.

oohryry;

What could be better than cold Budweiser, Marlboro's & good old fashioned "FILTH" ?........It's the American Way. I've been thinking about getting up early Christmas morning and doing mine......

Seriously though, if you have found someone that will remove the throttle body (important), give it a thorough bath (to spotless condition) and re-install it, jump all over it! That's a deal. If he cleans it properly, you should not be able to tell it from a new part. That's why I'm so adamant about (you, or anyone) not buying a new one. With nc's post for online parts, you should have found that the price is in the $700 to $800 range for just the part. DON'T DO IT! Get it cleaned! Spend the $100 for cleaning & buy a code reader (AutoXray 6000) for $425.00. You will be so happy being able to know when a repair shop (did someone say "stealer"?) is feeding you a line of crap.

I don't remember who the other poster was, but he had something like a quarter billion/trillion miles on his & all he ever did was clean it periodically.

If your guy just sprays some carb cleaner on/in the throttle body, save your money and do it yourself.

BTW.......Thanks nc......I'm humbled.......Muchos Gracias

[monarch]

Toyota says only the throttle plate (butterfly valve) and interior walls of the throttle body need to be cleaned. http://i5.photobucket.com/albums/y189/mastertech/tbclean.jpg The throttle body does not need to be removed. Use only small amounts of cleaner and scrub surfaces clean with a toothbrush. Then wipe away the accumulated goo with a clean towel moistened with the cleaner.

Using large amounts of cleaner could be harmful to the oxygen sensor, catalytic converter and nearby sensitive electrical components like the throttle position sensor.

[morg96ls400]

Toyota says only the throttle plate (butterfly valve) and interior walls of the throttle body need to be cleaned. http://i5.photobucket.com/albums/y189/mastertech/tbclean.jpg The throttle body does not need to be removed. Use only small amounts of cleaner and scrub surfaces clean with a toothbrush. Then wipe away the accumulated goo with a clean towel moistened with the cleaner.

Using large amounts of cleaner could be harmful to the oxygen sensor, catalytic converter and nearby sensitive electrical components like the throttle position sensor.

Throttle plate and interior walls are exactly where the name implies, on the throttle body facing the inside the intake chamber. Hence, being able to clean this area thoroughlywithout removing the throttle body as you suggest is impossible. When you disconnect the throttle position sensor you remove it from harm's way, as you do not spray the exterior of the throttle body, just the interior walls. Also, when you clean the intake chamber you wipe out after you spray, doing this several times to remove the layer of grime. Being careless and spraying it too much, leaving it in there and starting your car immediately WILL damage things.

I believe the 00-present have electric throttles, so i'm not sure if those are disconnected more easily (a simple connector for example) rather than the actual cables.