Engine dies, no idle unless pressing gas - Runs smooth and NO CODES....

George4drV6 · 12-23-2012, 10:03 AM

Hey Taco brethren. Long tim no post

Truck has been running smooth until last night I pull up to a stop light on my way home and the engine just dies as I come to a stop. It will not start at all unless I am pressing the gas. When I DO press the gas it starts up and runs just fine until I pull my foot off the gas.

I am not getting any codes and it idles completely smooth when I am holding the gas pedal and even let it down to 600 rpm or so.

I am thinking this is an IAC issue and/or bad EGR but this is a complete binary issue (running or dead) as it's never had a bad idle or stalling issues before even now there is no idle unless Im pushing down on the gas.

Let me know your thoughts.

2001 Tacoma 3.4 Auto
130k miles
At 95k I did plugs and wires
At 115k I did new timing belt and fuel filter

SDRD · 12-23-2012, 10:53 AM

You can remove the IAC from the throttle body and clean it just make sure you get a new IAC gasket and throttle body gasket. You should be able to take apart valve itself (electric motor and mechanical valve)

I found the best way to clean all te carbon in it without damaging it is soaking the mechanical part in ATF for a few hours then a little brake clean just to clean of the ATF

I have seen some fail out of no where so without codes it's an easy place to start

Also check your throttle position sensor. There should be a procedure to test it with a volt meter

Enola Gaia · 12-23-2012, 11:13 AM

If you weren't having idle issues prior to the engine dying last night, I'd definitely include the throttle position sensor as a possible culprit.

George4drV6 · 12-25-2012, 02:02 PM

Huge help guys. I'll be doing this work tomorrow and report back.

George4drV6 · 12-28-2012, 05:06 PM

Truck is FIXED. Not 100% sure of the exact issue but I did the following.

1) Completely cleaned out the IAC valve. It was very dirty, gummed up and scrubbed with chem tool carb cleaner and a tooth brush.

2) Replaced the Throttle Positioning Sensor. I figured I might as well change this out when I had the Throttle Body pulled off.

3) Cleaned out the throttle body and butterfly

Cleaned MAF, changed airfilter, and cleaned out the airbox and intake tube just for fun as well.

Starts and idles very smooth now so it seems the issue is completely fixed.

Thanks guys.

Enola Gaia · 12-28-2012, 06:05 PM

Glad you got it resolved ...

tacomatic1 · 12-29-2012, 12:01 PM

I bet your IAC was sticking, and not allowing for sufficient air to make it into the motor for it to idle. This would make sense why your motor would only run when you opened the throttle plate.

ENOSHbeatpuppet · 01-16-2013, 10:09 AM

Yup, my roommate's 2002 Tacoma was doing the same... dying out soon after start because it wouldn't hold idle unless you gave it some gas. Took apart his TB and IAC and cleaned it out. Starts up nicely and idles smooth now.

Took only a couple hours... so decided I should and need to clean mine out, opened up my 1996 2.4L Tacoma. 16+ years - Oh man was this long overdue.

Now she purrs like a cat.

(If you love your truck, don't let your TB or IAC get this dirty)