Installed the 1zz throttle body -

[AlexNet0]

I installed the 1zz throttle body today, and after everything was bolted back up, the engine oscillated terribly, I was expecting the 2-3k revs, but then after a few minutes it started to rev weird, eventually dropping off and starting to rough idle between 500 and 2k rpm, I attempted to purge the air from the lines, and got a few bubbles out of the coolant, and no more were coming out, but it did the same thing. No CEL was present during this.

So to prevent damage, I took it off and re-installed the stock throttle body, as I was doing this, I noticed that there was no coolant passing through the 1zz throttle body, the lines were empty. however when I bolted back up the stock TB and everything connected again, it oscillates between 2-3k rpm still, although I again purged the air from the coolant, getting more bubbles than I did with the 1zz TB.

What could this be from? I was shocked when I put the stock throttle body back on and it still oscillated like that.

[ddongbap]

You gotta give it a while for the ECU to fix itself.

Right now, you're in limbo. The ECU thinks that it still has the 1zz TB in it, so its trying to fix the 1zz TB settings, when you're still rocking the stock one. Just stick to one for a little bit.

That coolant line just helps unfreeze the TB if you're in a region where stuff will freeze overnight. Doesn't really have anything to do with the idle.

[AlexNet0]

You gotta give it a while for the ECU to fix itself.

Right now, you're in limbo. The ECU thinks that it still has the 1zz TB in it, so its trying to fix the 1zz TB settings, when you're still rocking the stock one. Just stick to one for a little bit.

I hope so, so what should I do, leave it overnight? should I disconnect the battery overnight?

[ddongbap]

Originally Posted by AlexNet0

I hope so, so what should I do, leave it overnight? should I disconnect the battery overnight?

I mean run your car with one TB. Just put up with the crappy idle for a day or so.

[AlexNet0]

man, lol, thanks for the quick reply, so driving with it like that is the best solution?
I mean disconnecting the battery wont reset the ECU back to normal overnight?

[thebarber]

you use a gasket maker for the 1zz throttle body?

and you need to let the car idle for 10min or so w/ the new throttle body on it so the ecu can learn that its there...

[AlexNet0]

no, I used the stock gasket, , but it felt like it sealed okay, perhaps not. anyway I will go sit in my car for like 10 minutes and see if the idle levels back out with the stock TB, thanks

[ddongbap]

Originally Posted by AlexNet0

man, lol, thanks for the quick reply, so driving with it like that is the best solution?
I mean disconnecting the battery wont reset the ECU back to normal overnight?

it might. But it would be better if the ECU figured it out.

[ddongbap]

Originally Posted by AlexNet0

no, I used the stock gasket, , but it felt like it sealed okay, perhaps not. anyway I will go sit in my car for like 10 minutes and see if the idle levels back out with the stock TB, thanks

Does the stock gasket seep into the 1zz TB? Or does it clear the bigger hole?

[FunctionSpec]

You need to get all the air out of the coolant. Its important that you do. Gently squeeze the lines and get the air bubbles moving out of the coolant. Gently rev it to get the coolant flowing. A large air bubble can cause an air-lock in the coolant that prevents the coolant from flowing through the throttle body and back into the coolant system.

Air bubbles cause the oscillations because of the difference in temperature. Air heats up faster then coolant so whenever an air bubble passes over the coolant temp sensor, it lowers the idle thinking the engine is warmed up and then when the colder coolant passes over, it raises the idle thinking the engine is still cold.

ECU doesn't need to "learn" anything. It adjusts accordingly to how much air is flowing in. You will always have a high idle on a cold startup with this setup because the ecu doesn't start measuring airflow 10secs after startup. Once it does start measuring, it'll adjust the idle.

[AlexNet0]

I purged the air from the stock TB three times after re-installing it.

started up from cold, removed cap (not reservoir cap) and squeezed the coolant lines going to the TB until no more bubbles came up. Let the car cool down and did it again till there were no more bubbles.



should probably point out that I was tired of messing with it at that particular time as it was 13 degrees F and I was running out of daylight (no garage) just so people dont think Im a little b*tch lol

[AlexNet0]

I just drove around for like a half hour and the revs dropped from 3k to 2k fully warmed up, Ill see how it is tomorrow

[thebarber]

Originally Posted by AlexNet0

no, I used the stock gasket, , but it felt like it sealed okay, perhaps not. anyway I will go sit in my car for like 10 minutes and see if the idle levels back out with the stock TB, thanks

you should use some gasket maker....the stock gasket isnt big enough for the new throttle body...

[ddongbap]

Originally Posted by FunctionSpec

You need to get all the air out of the coolant. Its important that you do. Gently squeeze the lines and get the air bubbles moving out of the coolant. Gently rev it to get the coolant flowing. A large air bubble can cause an air-lock in the coolant that prevents the coolant from flowing through the throttle body and back into the coolant system.

Air bubbles cause the oscillations because of the difference in temperature. Air heats up faster then coolant so whenever an air bubble passes over the coolant temp sensor, it lowers the idle thinking the engine is warmed up and then when the colder coolant passes over, it raises the idle thinking the engine is still cold.

ECU doesn't need to "learn" anything. It adjusts accordingly to how much air is flowing in. You will always have a high idle on a cold startup with this setup because the ecu doesn't start measuring airflow 10secs after startup. Once it does start measuring, it'll adjust the idle.

Isn't that what learning is? Wouldn't that also explain why the stock TB is causing problems after he took the 1zz TB out?

[YarisSedan]

Seeing its a larger throttle body. Say the computer needs to open the throttle 10 percent to let in a certain amount of air. With a larger throttle 10 percent is really like 25 percent. Which is why you will always have a high idle. But why you also get better throttle response and power. Because say you want to open the throttle to 50 percent normall its more like 75 percent if you compare the amount of air being sucked into the engine.

I would not attempt this mod till you have exhausted other possiblities of increasing power such as a AFE intake or trd exhause or headers. Before slapping on the throttle body.

[AlexNet0]

solved the issue, I disconnected the battery for 5-10 minutes and when I connected it again..No more odd revs. Note that this is the stock TB that I was having issues with.

I would not attempt this mod till you have exhausted other possiblities of increasing power such as a AFE intake or trd exhause or headers. Before slapping on the throttle body.

I do not have money for exhaust or header, or I would have them already, I have a cold air that is working nicely for me now.

you should use some gasket maker....the stock gasket isnt big enough for the new throttle body...

how did you apply the gasket maker? To the Manifold side or the TB side?

[ddongbap]

Originally Posted by YarisSedan

Seeing its a larger throttle body. Say the computer needs to open the throttle 10 percent to let in a certain amount of air. With a larger throttle 10 percent is really like 25 percent. Which is why you will always have a high idle. But why you also get better throttle response and power. Because say you want to open the throttle to 50 percent normall its more like 75 percent if you compare the amount of air being sucked into the engine.

I would not attempt this mod till you have exhausted other possiblities of increasing power such as a AFE intake or trd exhause or headers. Before slapping on the throttle body.

I think this TB would yield better results than an intake, and exhaust.

[AlexNet0]

Ill try it again when its warmer out or I find someones garage to work in, its negative 7 right now.