2006 Yaris Cold Start problems

[cerberii]

Hi, I need to rev when i cold start or start driving right away. If I dont then the engine putts along (missing) and eventually dies. After a few minutes of 1500 rpm idle by gas pedal pressure it idles and runs normally. Or after about 5 or 10 starts and dying it will then idle normally.

Is this the throttle body (ICV) that needs cleaning? MAF sensor? PVC? Bad Gas? Fuel system? Motor is finished?

Manual says when theres a problem with the air/fuel mixture it will do this cutout, and best way is to reset computer (off/on).

Any ideas? :bow:

edit:

I have tried cleaning the MAF sensor, and then cleaning PVC, and air filter, then did a reset on the computer. This time it started and seemed to be fixed. After a few minutes though it started putting at 500 rpm and then died.

Seems now it always idles at 500 rpm instead of 1000 rpm though during the cold start or randomly even when its warm?

update 1:
Cleaned air intake system everything is renewed, cleaned the throttle body and intake manifold, new plugs, still dies on cold start if i dont hold the rpm at 2000 until warm.

Opened the gas tank, took teh gas filter/motor out and cleaned it started up again, we'll see if i fixd it tommorow morning for the traditional cold start misfires and stalls

[ex-x-fire]

First off, is there any codes?

[cerberii]

First off, is there any codes?

There are no engine lights or anything. I dont have a code reader so I cant tell if there are any codes.

edit: Ok I just got check engine light now. I unplugged MAF while running to see if engine died, and it did. So MAF seems to be functioning properly.

[miiser]

Maybe a fuel injector has dirt ??



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[B.B._07]

First of all get the codes scanned, they'll point you in the right direction. Check that you have spark, and the condition of the ignition coils. Also check that you're getting fuel, so check the fuel pump primes and runs, and that you're getting good fuel pressure.

[cerberii]

First of all get the codes scanned, they'll point you in the right direction. Check that you have spark, and the condition of the ignition coils. Also check that you're getting fuel, so check the fuel pump primes and runs, and that you're getting good fuel pressure.

theres no codes because there is no check engine light. I reset the computer and theres no check engine. This is something that is not throwing a code. I got it to throw a code by disconnecting the MAF while running, but that was just because I removed the MAF, so it recorded the code and displayed the check engine light. After reset it was fine and no check engine, no code then?

everything runs great when its warm. Its just the cold start. Starting cold it will go to 1000rpm then down to 500 and then a few minutes later sputter and die. Before cleaning the MAF/PVC and restarting the computer it went to 1000 and then just died ( upon cold start).

Just replaced air filter and spark plugs as well right now, on cold start it still will idle too low and then sputter and die. Im thinking this could be the ICU in the throttle body, and maybe needs to be cleaned?

[cerberii]

help?

[AumesiAdA]

good day everyone!
i am sorry but im a newbie here,
i want to know how to post a new topic?
i have some questions about my yaris 2012
thank you

[Kousi]

Did u get it fixed ? I have same problem and it is frustating as hell

[ArmstrongRacing]

Maybe if its super cold, there is a possibility of ice forming the MAF sensor or throttle plate.

Also most sensors can only read down to -40F, so if its colder than that I could see there being issues.

A vacuum leak causes a bunch of issues on these engines as well