My wife has a 98 SC300 that is having problems with the APPS. I drive an old Land Cruiser and hate this car, so we're trying to sell it. I've done some reading and it has been suggested that replacing the throttle body is the easiest thing to do. I am having a confusing time finding a used one online, so I have a few questions to broaden my search parameters.

1. Is a throttle body for a 300 the same for 400?
2. Can a throttle body for other years be used for a 98?
3. Did they use the same throttle body on different models?
4. Are there other questions I should be asking?

Thanks in advance

 

1. nope, people have the gs400 vvti ones welded to the 2jzge Y pipe so they can run the larger one.
2. throttle bodies of 98+ only
3. I think all the vvti 2jzge motors had very similar setups if not identical and I know the throttle bodies will bolt on. as for working 100% with ecu not sure but I would think so, all is300 are vvti 2jzge and later model GS has vvti 2jzge as well.
4. how do you know its the APPS. check engine light code?? you could have an entirely different problem bringing that code up.

you may not have to replace the whole thing. I think the cable goes to the throttle body and then there is a sensor on the other side that measures the position. maybe the sensor can be changed or if not finding another throttle body is probably your best bet. I know there is a ton of info on these on the IS forum. maybe check out that site and see if there is a fix. I know of a few workarounds involving going back to a non vvti throttle body but these would not be what you would want if you were trying to keep it stock as the ecu is no longer controlling it. I would try and find the fix first then replace.

 

It first happened about a month ago, while my wife was driving. She tried to pull out of a parking lot and the car wouldn't go until she floored it and then it took off. We had it towed to AAA and they told me it was the APPS and they wanted $2200 to fix it. As I mentioned, I don't like the car, so bought a 4runner instead of fixing it. I took it to another shop and told them what was said by AAA and they checked the sensor, which tested out at 900 ohms, which is lower than the 1000-1300 they said it should be. However, they couldn't get it to replicate the issue. I then drove it to my in-laws because my father-in-law was going to borrow it. He drove about four miles before doing it again. The CEL has not come on at any time, so it's not throwing codes.

 

Probably just needs adjustment on the tps or something like that. I wouldn't consider 900 a definite out of range from 1000-1300. If its cold enough it could read slightly below spec.
They always want to replace instead of diagnose they see it as a win win, except your pocket book looses every time.
I think the replacement is only a few hundred and if you can use a screwdriver and a few sockets you could probably DIY.