96 Tercel fast idle...help needed

[Jbobyk]

Hi, i am new to the forum. I just purchased a 96 tercel and it runs great, drives awesome no problems but i noticed it idles quite high. Its around 1500 rpm and can get up to 1750rpm. I have some mechanical knowledge and decided to check around the throttle body for vaccume leaks and nothing jumped out as being bad or in need of service. I was hoping to find a idle screw on the throttle body that i could turn down but i have to now assume its controlled by the ECM. I don't have a check engine light on, i don't have any drivability issues it runs smooth.

Anyone have any ideas where to start

Also is there such thing as a repair manual for these beasts? dealer manual? cant find a haynes or a chilton for the year i have.

[noahthefrog]

For the manual, it looks like you're only option is the official toyota manual. They are expensive

Here's a used one on ebay for about $80: http://cgi.ebay.com/ebaymotors/1996-Toyota-Tercel-Service-Shop-Repair-Manual-Oem-96-_W0QQcmdZViewItemQQitemZ160466583051QQptZMotorsQ5f ManualsQ5fLiterature

I don't know how your year tercel achieves high idle. It is normal for the engine to idle higher like you describe when the AC is on, when the engine is cold and possibly for other reasons too. If it's doing that all the time, perhaps it thinks the AC is on or the engine isn't warmed up because of faulty relay or sensor (coolant temperature sensor, perhaps?).

[Jbobyk]

thanks for the tip on the manual for the car...if i have a manual i can do anything to one of these its working blindly that makes me nervous. I am pretty sure my high idle is related to the vaccume system. I am going to clean my EGR valve and replace the vacuume lines. I was also told these cars from 95 and up have an idle air control valve which could also be faulty. I have no clue how to go about testing the valve so i'll start with the EGR and work towards it. hopefully it will work the problem out

[Daox]

I'd try cleaning out the IAC valve. Its directly under the throttle body (attached to it). If you spray carb cleaner in the closed throttle, it will go through the valve. Spray some in and let it sit for a while. Then, rev the engine up and down a bit, and keep spraying it. That will make the valve try to actuate and hopefully it'll break free.

[doug1717]

Look for the Haynes manual, it is cheap and helpful.
It could be a vacuum leak, where the engine sucks in extra air from a loose or cracked vacuum line.
Open the hood and look under it, there should be a map showing you the vacuum lines.
Double check them.

[bkftl]

before u go blowing money on stuff, read this

i had same problem after we put in a new engine, make sure that the actual throttle cable and the thing that rotates with the cable "throttle pulley?" is actualy pushed all the way back. its held by a spring,

On most used cars stuff like gets worn out. after we assebled engine and stuck it into car, it was idling too high too, simply push back that damn thing, and fix that spring, and that spring is usualy rusty and old... u can replace it for any simular spring, just not too tight and same size, u can get one at homedepot for less then a few bucks?

we thought it was a vacume problem too and stuff, nearly tore the engine appart again

hope that helps :P

[Jbobyk]

ok well i went to an auto wrecker and ripped out alot of parts off another 96 tercel. I grabbed the coil packs, complete throttle body assembly with sensors, and the egr valve. I took the throttle body apart and completly cleaned with throttle body cleaner. I am going to re assemble today and swap out with my old one. hopefully it clears up my idle issue. Dealer wants almost $600 for the IAC sensor and probable another $500 to diagnose my problem. i'll take the $20 throttle body and swap and do some guess and check for that price.

[doug1717]

One way to look for a possible vacuum leak is to run the motor and spray brake cleaner around your lines and seals. If there is a leak, the brake cleaner gets sucked in and the revs will drop, and a small puff of white smoke will come out the exhaust.

The O2 sensor is reading more oxygen in the exhaust and it is reacting by increasing revs.

The O2 sensor does this when you hit the gas peddle and let more air in the fuel air mix.

[Jbobyk]

looks like cleaning the throttle body and specifically dissasembling and cleaning the IAC sensor made a huge difference! My IAC was siezed. looks like a build up of carbon was the cause, i also removed and replaced my EGR. At operating temp i idle at 750 rpm.

Thanks for everyones help!

[Tercel GTS]

Glad to see your problem was fixed. It's a great thing when we can help each other. How many miles does your car have so other people that search this thread out can compare.