1zz TB CEL?

[Black_griffin6]

Hey guys,

I installed the 1zz throttle body a while ago (probably a good 2 months ago). Now all of a sudden I keep getting a CEL with the code P0 505 (which has something to do with the idle).

I have no idea why this is happening, the only mods I did since then was some TRD upper strut mounts and TRD rollstopper AKA the TRD rear transmission mount.
I have noticed it's idling a little high whenever this happens, i've reset the ECU twice already and this is the third time i've got a CEL.

Any ideas as to why this is happening all of a sudden? It was fine for a long time up until recently. :iono:

EDIT: I should also note: The only other intake mods are a Weapon R secret weapon intake, and the air filter is still pretty clean. And engine mods are a pulley kit, DC header, and Mandrell bent cat back exhaust.

[mazilla]

ECU doesn't seem to like idles above the 750/850ish mark(although I've gone a day or two at 1,000rpm without the CEL). I've also noticed the CEL might kick on after a low idle event when the car goes down below 400ish.

You mentioned high RPM, what about low(borderline stall)?

I'm always driving when trying to take note of these things so it's hard to pinpoint the exact moment for 100% certainty.

[Black_griffin6]

My normal idle seems to be around 6-700 ish, but when the CEL comes on it's more around 8-900.

It never idles very low like it's about to stall though.

[tooter]

Hey guys,

I installed the 1zz throttle body a while ago (probably a good 2 months ago). Now all of a sudden I keep getting a CEL with the code P0 505 (which has something to do with the idle).

I have no idea why this is happening, the only mods I did since then was some TRD upper strut mounts and TRD rollstopper AKA the TRD rear transmission mount.
I have noticed it's idling a little high whenever this happens, i've reset the ECU twice already and this is the third time i've got a CEL.

Any ideas as to why this is happening all of a sudden? It was fine for a long time up until recently. :iono:

EDIT: I should also note: The only other intake mods are a Weapon R secret weapon intake, and the air filter is still pretty clean. And engine mods are a pulley kit, DC header, and Mandrell bent cat back exhaust.

When you installed your 1ZZ did you chip the epoxy off the factory set idle screw and turn it out about one turn to let the butterfly close more?

(top of picture, tiny allen head screw pointing to the left)

http://i17.photobucket.com/albums/b90/compost_bin/car/IMG_6636_zps7adb8dbd.jpg

The 1ZZ butterfly is factory set to idle a 1.8 and flows way too much air at idle for a 1.5. Try turning the idle down while your battery cable is off the negative terminal. Reset it and see if that helps.

[Black_griffin6]

No I didn't, I might have to try that.
Like I said, it was fine for the longest time up until recently.

Which way would I have to turn the screw? Clockwise or counter-clockwise? And is it a full 360 degree turn or 180 degree turn?

[CrankyOldMan]

"Out" would be counter-clockwise. Just be very careful with the socket on that thing--they strip very easily if you don't have the threads broken loose.

[tooter]

What he said. /\/\

My 1ZZ was doing all sorts of crazy ass stuff until I turned the idle down. Once I did, everything worked just fine and I haven't touched it since. :thumbsup:

The cold idle will always be fast at 2,000 rpm because that butterfly position is preset by the signals from the ECU, but it drops rapidly down to normal as the engine warms up.